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تنشهای محیطی در علوم زراعی - سال دوازدهم شماره 2 (تابستان 1398)

مجله تنشهای محیطی در علوم زراعی
سال دوازدهم شماره 2 (تابستان 1398)

  • تاریخ انتشار: 1398/03/29
  • تعداد عناوین: 26
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  • مهدی زهدی اقدم، فرخ درویش کجوری*، مهدی غفاری، آسا ابراهیمی صفحات 331-346
    بررسی ترکیب پذیری عمومی و خصوصی لاین ها تحت شرایط آبیاری مطلوب و محدود به منظور استفاده والدین در ایجاد واریته های هیبرید جدید ضروری است. افزون بر این، نوع وراثت صفات می تواند در تصمیم گیری برای تعیین روش های اصلاحی مناسب و پیش بینی میزان پیشبرد ژنتیکی ناشی از گزینش کمک کند. در این پژوهش که در دو سال زراعی 93-94 در ایستگاه تحقیقات کشاورزی خوی انجام گردید به منظور بررسی ترکیب پذیری عمومی و خصوصی در آفتابگردان، پنج لاین نرعقیم و چهار تستر بازگرداننده باروری به صورت لاین در تستر در سال 1392 تلاقی داده شدند. هیبریدهای حاصل در قالب طرح بلوک های کامل تصادفی با سه تکرار برای آبیاری مطلوب و سه تکرار برای تنش بررسی شدند. نتایج تجزیه واریانس ساده در شرایط مطلوب برای کلیه صفات معنی دار و در شرایط محدود نیز برای کلیه صفات به جز وزن هزار دانه، رطوبت نسبی، عملکرد دانه، عملکرد روغن معنی دار گردید. درصورتی که نتایج تجزیه واریانس مرکب برای صفات مختلف در شرایط مطلوب و محدود نشان داد که میانگین مربعات به جز صفت رطوبت نسبی در شرایط محدود برای صفات ارتفاع بوته، قطر طبق، تعداد دانه در طبق، وزن هزار دانه،، پرولین، آنزیم کاتالاز، آنزیم سوپر اکسید دیسموتاز، کلروفیل a، کلروفیل b، عملکرد دانه و عملکرد روغن معنی دار بود. نتایج به دست آمده از تجزیه واریانس مرکب داده ها حاکی از معنی دار بودن ترکیب پذیری عمومی برای لاین ها و تسترها و همچنین ترکیب پذیری خصوصی (لاین × تستر) برای اکثر صفات بود. بر اساس ارزیابی ترکیب پذیری ها لاین AGK30 و AGK44، تستر RGHK25 و RGHK50 و هیبرید RGHK56×AGK44 به ترتیب مناسب ترین لاین، تستر و هیبرید در هر دو شرایط تعیین شدند.
    کلیدواژگان: ترکیب پذیری خصوصی، ترکیب پذیری عمومی، تستر، لاین
  • حال بی بی بادیردست، سید یحیی صالحی، حسین صبوری*، علی موافقی، ابراهیم غلامعلی پور علمداری صفحات 347-363
    خشکی یکی از تنش های محیطی است که رشد، نمو و عملکرد برنج را محدود می سازد. پیچیدگی روابط بین صفات از مسائلی است که فرآیند اصلاح واریته های متحمل به تنش خشکی را مشکل می نماید. امروزه از تکنیک های گرافیکی جدیدی برای بررسی اثر صفات با در نظر گرفتن اثرات متقابل آن ها استفاده می شود یکی از این روش ها GGE biplot است. این تحقیق برای بررسی تاثیر تنش خشکی بر صفات زراعی و مورفولوژیکی 263 ژنوتیپ برنج بر اساس طرح لاتیس در دو شرایط بدون تنش و تنش آبی در طول فصل زراعی سال 1394 انجام شد. داده ها با روش آماری تجزیه واریانس و GGE biplot موردبررسی قرار گرفتند. نتایج تجزیه واریانس نشان داد که سه عامل محیط، ژنوتیپ و اثر متقابل محیط × ژنوتیپ در اکثر صفات موردبررسی بسیار معنی دار بود. تجزیه GGE biplot نیز نشان داد که در شرایط بدون تنش و تنش خشکی عملکرد دانه رابطه مثبتی با وزن دانه پر، تعداد دانه پر، وزن خوشه اصلی، وزن کل خوشه ها، قطر ساقه، تعداد خوشه چه ثانویه، تعداد خوشه چه اولیه، بیوماس، شاخص برداشت و باروری داشت. همبستگی مثبت و معنی دار بین اکثر صفات نشان می دهد که یکی از این صفات می تواند به عنوان معیار انتخاب مورداستفاده قرار گیرد. ژنوتیپ HHZ 10-DT5-LI1-LI1 در شرایط بدون تنش با دارا بودن بالاترین میزان عملکرد دانه (146.69 گرم)، دانه پر (224.83)، وزن دانه پر (4.66 گرم) و شاخص برداشت (1.25) برترین ژنوتیپ در این محیط بود و ژنوتیپ HHZ 18-Y3-Y1-Y1 با بالاترین میزان وزن کل خوشه ها (46.5 گرم)، وزن خوشه اصلی (3.80 گرم)، تعداد دانه پر (207.5) و وزن دانه پر (3.42 گرم) و عملکرد (71.82 گرم) به عنوان ژنوتیپ متحمل شناسایی شد. از این ژنوتیپ ها می توان در برنامه های اصلاحی برای بهبود تحمل به تنش خشکی به خصوص در مناطق خشک و نیمه خشک استفاده نمود.
    کلیدواژگان: برنج، تجزیه GGE biplot، تنش خشکی، تنوع ژنتیکی
  • حمید دهقان زاده* صفحات 365-375
    به منظور بررسی تاثیر تنش خشکی بر شاخص های فیزیولوژیکی، عملکرد و برخی اجزای عملکرد دانه سه رقم گندم نان (Triticum aestivum L.)، آزمایشی در سال زراعی 93 - 1392 به صورت کرت های خردشده، با طرح پایه بلوک کامل تصادفی در چهار تکرار در شهرستان تیران اصفهان به اجرا درآمد. تنش خشکی با سه سطح (آبیاری پس از 70، 90 و 110 میلی متر تبخیر تجمعی از تشتک تبخیر کلاس A، به ترتیب به عنوان عدم تنش، تنش ملایم و شدید) در کرت های اصلی و سه رقم گندم سپاهان، قدس و پیشتاز در کرت های فرعی قرار گرفتند. تغییرات شاخص سطح برگ، روند تجمع ماده خشک کل، سرعت اسیمیلاسیون خالص، سرعت رشد محصول و عملکرد دانه ارقام گندم موردبررسی قرار گرفت. نتایج نشان داد، افزایش شدت تنش از 90 به 110 میلی متر تبخیر تجمعی، باعث کاهش معنی دار در میانگین شاخص های رشدی و عملکرد دانه شد. تحت تیمارهای آبیاری پس از 70 و 90 میلی متر تبخیر تجمعی، روند تغییرات شاخص سطح برگ، ماده خشک کل، سرعت اسیمیلاسیون خالص و سرعت رشد محصول شباهت زیادی به یکدیگر داشت. این در حالی بود که در همه نمونه برداری ها با افزایش فاصله دو آبیاری از 90 به 110 میلی متر تبخیر تجمعی، کاهش معنی داری در روند تغییرات شاخص سطح برگ، ماده خشک کل و سرعت رشد محصول مشاهده گردید؛ بنابراین ممکن است در شرایط آب و هوائی مشابه با انجام آبیاری گندم بر اساس 90 میلی متر تبخیر از تشک تبخیر کلاس A، ضمن کاهش 22 درصد در مصرف آب آبیاری، شاخص های رشدی و عملکرد دانه هم به طور معنی داری تحت تاثیر قرار نگیرد.
    کلیدواژگان: سرعت اسیمیلاسیون خالص، سرعت رشد محصول، شاخص سطح برگ، ماده خشک کل
  • عمران پارساپور، عبدالمهدی بخشنده*، محمدحسین قرینه، حسن فیضی، محمدرضا مرادی تلاوت صفحات 377-388
    به منظور بررسی تاثیر محلول پاشی سیلیسیم بر عملکرد و توزیع مجدد ماده خشک گندم در شرایط تنش خشکی، پژوهشی مزرعه ای در سال زراعی 95-1394 به صورت کرت های خردشده در قالب طرح پایه بلوک های کامل تصادفی در چهار تکرار در دانشگاه علوم کشاورزی و منابع طبیعی رامین خوزستان اجرا گردید. تیمار تنش خشکی شامل سه سطح آبیاری نرمال (بدون قطع آبیاری یا شاهد)، تنش خشکی از زمان ساقه روی تا گل دهی و تنش خشکی از گل دهی تا رسیدگی دانه به عنوان فاکتور اصلی و محلول پاشی سطوح دی اکسید سیلیسیم در هفت سطح شامل بدون سیلیسیم (شاهد)، کاربرد ذرات نانو و غیرنانو سیلیسیم در غلظت های 50، 100 و 150 میلی گرم در لیتر به عنوان فاکتور فرعی در نظر گرفته شدند. نتایج نشان داد که تنش خشکی در دوره ساقه روی تا گل دهی عملکرد دانه گندم نسبت به شرایط آبیاری معمول را در حدود 35 درصد کاهش داد. محلول پاشی سیلیسیم تا حدودی تاثیر منفی تنش خشکی بر عملکرد دانه را تقلیل داد. عملکرد دانه گندم با کاربرد غلظت 100 میلی گرم در لیتر سیلیسیم نانو (577.61 گرم در متر مربع) و 150 میلی گرم در لیتر سیلیسیم غیر نانو (527.73 گرم در متر مربع) به طور معنی داری بیشتر از سایر تیمارهای محلول پاشی شد. صرف نظر از تیمارهای محلول پاشی، توزیع مجدد ماده خشک در شرایط آبیاری معمول در حدود 11 درصد کمتر از شرایط تنش خشکی بود. بیشترین سهم توزیع مجدد از عملکرد دانه گندم مربوط به محلول پاشی با غلظت 100 میلی گرم در لیتر سیلیسیم نانو در شرایط تنش از گلدهی تا پایان دوره رشد بود. همچنین تنش خشکی سهم فتوسنتز جاری در پر کردن دانه ها را به طور معنی داری کاهش داد.
    کلیدواژگان: توزیع مجدد ماده خشک، فتوسنتز جاری، کارایی توزیع مجدد
  • فرشاد سرخی*، مجتبی فاتح صفحات 389-399
    جهت بررسی اثر تنش خشکی بر شاخص سطح برگ، سرعت فتوسنتز، میزان کلروفیل، هدایت روزنه ای و میزان پرولین در ارقام لوبیا چیتی، آزمایشی بصورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با چهار تکرار اجرا شد. تیمارهای آزمایش شامل تنش خشکی در سه سطح، آبیاری کامل (شاهد)، قطع آبیاری در مرحله رویشی شامل ظهور سه برگچه اول (V3) و قطع آبیاری در مرحله گلدهی (R6) و دو رقم لوبیا چیتی (تلاش و خمین) بودند. نتایج نشان داد در هر دو رقم لوبیا چیتی شاخص سطح برگ، میزان کلروفیل a و b، سرعت فتوسنتز و هدایت روزنه ای در اثر تنش خشکی کاهش معنی دار یافت ولی بر میزان پرولین بطور معنی داری افزوده شد. تحت تنش، بیشترین مقدار کاهش در صفات به ترتیب به محتوای کلروفیل a، شاخص سطح برگ، هدایت روزنه ای، سرعت فتوسنتز و محتوای کلروفیل b اختصاص داشت. ارقام لوبیا از لحاظ شاخص سطح برگ و میزان کلروفیل b، تحت شرایط آبیاری کامل فاقد اختلاف معنی دار بودند ولی در شرایط اعمال تنش خشکی، رقم تلاش در مقایسه با رقم خمین به طور معنی داری از کاهش کمتر هدایت روزنه ای، میزان کلروفیل و سرعت فتوسنتز برخوردار بود. میزان کاهش هدایت روزنه ای در تنش خشکی در مراحل گلدهی و رویشی نسبت به شاهد (آبیاری کامل) در رقم تلاش به ترتیب 25.69 و 46.29 درصد و در رقم خمین به ترتیب 38.90 و 57.81 درصد بود و افزایش محتوی پرولین نیز در رقم تلاش به ترتیب 56.46 و 92.51 درصد و در رقم خمین به ترتیب 43.97 و 81.45 درصد بدست آمد. نتیجه گیری شد رقم تلاش با دوام فتوسنتزی بیشتر از طریق حفظ سطح برگ، هدایت روزنه ای، سرعت فتوسنتز و میزان کلروفیل و افزایش مقدار پرولین در شرایط تنش خشکی مقاوم تر از رقم خمین است.
    کلیدواژگان: برگ، خشکی، فیزیولوژی، کلروفیل، لوبیا
  • احمد قاسمی*، مسعود خزاعی، حمیدرضا فنایی صفحات 401-413
    با عنایت به محدودیت در فراهمی آب، تامین حد مطلوب و بهینه مصرف آب جهت دستیابی به عملکرد بالا و اقتصادی در زراعت ارزن حائز اهمیت است. این پژوهش برای ارزیابی اثر تنش خشکی بر عملکرد و برخی خصوصیات فیزیولوژیک ارزن دم روباهی در تاریخ های مختلف کاشت انجام شد. آزمایش مزرعه ای به صورت کرت های خردشده در قالب طرح بلوک های کامل تصادفی با سه تکرار در سال های 1391 و 1395 اجرا شد. تاریخ های کاشت (1، 15 و 30 اسفند و 15 فروردین) در کرت های اصلی و تنش خشکی (50، 65 و 80 درصد ظرفیت زراعی) در کرت های فرعی قرار گرفتند. در طول فصل زراعی صفات ارتفاع بوته، تعداد پنجه، طول پانیکول، عملکرد دانه، عملکرد علوفه تر و خشک، تعداد روز تا گل دهی، وزن هزار دانه، غلظت پرولین و محتوای کلروفیل تعیین شد. نتایج نشان داد که صفات اندازه گیری شده تحت تاثیر تاریخ کاشت قرار گرفت. کاشت گیاه در 15 اسفند بیشترین عملکرد دانه و صفات دیگر را تولید کرد. بیشترین کاهش عملکرد دانه مربوط به تاریخ کاشت 15 فروردین بود. عملکرد دانه و صفات فیزیولوژیک ارزن در اثر کمبود آب کاهش نشان داد. بیشترین عملکرد دانه در 50 درصد ظرفیت زراعی تولید شد. کمترین عملکرد دانه در 80 درصد زراعی به دست آمد، ولی غلظت پرولین در این تیمار بیشترین مقدار بود. عملکرد دانه در تیمار 50 درصد ظرفیت زراعی نسبت به تیمار 80 درصد، 74 درصد افزایش داشت. درمجموع عملکرد دانه و خصوصیات فیزیولوژیک ارزن به طور قابل توجهی از شرایط تنش خشکی تاثیر پذیرفت؛ بنابراین جهت دستیابی به بیشینه عملکرد دانه و علوفه، کاشت رقم باستان باید در تاریخ 15 اسفند و مدیریت آبیاری آن بر مبنای 50 درصد ظرفیت زراعی صورت گیرد.
    کلیدواژگان: پرولین، ظرفیت زراعی، علوفه، کمبود آب
  • محمودرضا تدین*، هدایت الله کریم زاده سورشجانی صفحات 415-427
    به منظور بررسی سطوح مختلف کم آبیاری و زئولیت بر ارزن پروسو (Panicum miliaceum L.)، آزمایشی به صورت بلوک های خردشده در تابستان 1394، در دانشگاه شهرکرد اجرا شد. عامل اول شامل: زئولیت (0، 0.5 و 1 کیلوگرم در مترمربع) و عامل دوم رژیم آبیاری (تامین 100، 75، 50 و 25 درصد نیاز آبی گیاه) بودند. نتایج نشان داد شاخص سطح برگ (LAI)، سرعت رشد گیاه (CGR)، سرعت جذب و تحلیل خالص (NAR) و سرعت رشد نسبی (RGR) تحت تاثیر تیمارهای کم آبیاری کاهش یافتند، اما کاربرد زئولیت باعث بهبود شاخص های مذکور در شرایط کم آبیاری شد. کم آبیاری سبب کاهش پایداری غشاء سلول، محتوای نسبی آب برگ، هدایت روزنه ای، زیست توده، عملکرد دانه و شاخص برداشت گردید درحالی که کاربرد زئولیت منجر به بهبود صفات مذکور در شرایط کم آبیاری گردید. بیشترین درصد کاهش عملکرد دانه (77 درصد) نسبت به تیمار شاهد در تیمار آبیاری 25 درصد ظرفیت زراعی و عدم استفاده از زئولیت مشاهده شد. بیشترین میزان عملکرد دانه نیز از تیمار بدون کم آبیاری و کاربرد نیم و یک کیلوگرم بر مترمربع زئولیت به دست آمد (به ترتیب 159 و 156 گرم بر مترمربع). بر اساس نتایج به دست آمده می توان نتیجه گیری کرد که کاربرد یک کیلوگرم زئولیت بر مترمربع برای دستیابی به عملکرد بهتر قابل توصیه است.
    کلیدواژگان: تنش خشکی، سرعت رشد نسبی، محتوای نسبی آب، هدایت روزنه ای
  • حسن قاسمیان اردستانی، محسن جهان*، امیر حسین شیرانی راد صفحات 429-443
    کم آبی از مهم ترین عوامل محدودکننده رشد و تولید گیاهان به حساب می آید و در حال حاضر هیچ راه عملی برای افزایش نزولات جوی در طول دوره های خشکی وجود ندارد؛ بنابراین، به نظر می رسد که بهترین راه مقابله با خشکی، به کارگیری عملیات زراعی مناسب و استفاده از ارقامی است که تحمل بیشتری به خشکی داشته باشند. این آزمایش به صورت فاکتوریل اسپلیت پلات در قالب طرح بلوک های کامل تصادفی با سه تکرار و به مدت 2 سال(95-1393) در منطقه کرج اجرا شد. در این تحقیق، فصل کشت در دو تاریخ (پائیزه و زمستانه) و آبیاری در سه سطح (آبیاری معمولی یا شاهد، قطع آبیاری از مرحله گل دهی به بعد و قطع آبیاری از مرحله خورجین دهی به بعد) به صورت فاکتوریل به عنوان عامل کرت اصلی و ارقام بهاره کلزا شاملجری، جولیوس، ظفر، آرجی اس 003، هایولا 4815 و زابل 10به عنوان عامل کرت فرعی در نظر گرفته شدند. بیشترین میانگین اسید لینولئیک در تیمار شاهد و رقم جولیوس، با میانگین 21.77 درصد حاصل شد. نتایج حاکی از آن بود که در تیمار شاهد و قطع آبیاری از مرحله خورجین دهی به بعد رقم جولیوس با مقادیر 66.29 و 64.16 درصد بیشترین مقدار اسید اولئیک را نشان داد و در شرایط قطع آبیاری از مرحله گل دهی به بعد رقم هایولا 4815 با میانگین 62.26 درصد، بیشترین میانگین را به خود اختصاص داد. اثر سال، فصل کاشت، آبیاری، سال×آبیاری، سال×فصل کاشت×آبیاری، فصل کاشت×آبیاری، رقم، فصل کاشت×رقم، آبیاری×رقم و فصل کاشت×آبیاری×رقم در سطح 1 درصد و اثر سال×فصل کاشت نیز در سطح 5 درصد بر عملکرد دانه و روغن معنی دار بود. نتایج حاصل از ارزیابی صفات طی دو سال آزمایش مشخص کرد که ارقام جولویس و هایولا 4815 دارای بیشترین عملکرد دانه در شرایط آبیاری بوده و همچنین رقم هایولا 4815 سازگاری مناسبی نیز به شرایط تنش خشکی داشتند؛ بنابراین، می توان ارقام مذکور را به دلیل داشتن عملکرد دانه و عملکرد روغن بالاتر تحت هر دو شرایط تنش خشکی و بدون تنش؛ جهت کاشت در مناطقی مشابه منطقه اجرای آزمایش (کرج) که احتمال وقوع تنش رطوبتی در مراحل انتهایی رشد وجود دارد، توصیه نمود. همچنین تاریخ کاشت پاییزه موجب افزایش مقادیر عددی شاخص های کیفی کلزا شد.
    کلیدواژگان: اسید پالمیتیک، اسید لینولئیک، تنش خشکی، کلزا
  • افسانه پیرمانی، تورج میر محمودی*، سامان یزدان ستا صفحات 445-457
    به منظور بررسی تاثیر دور آبیاری و مقادیر مختلف کود نیتروژن بر عملکرد و اجزای عملکرد و میزان اسانس همیشه بهار آزمایشی به صورت اسپیلت پلات در قالب طرح بلوک های کامل تصادفی در سه تکرار در بهار 1395در ایستگاه کشاورزی ساعتلوی ارومیه انجام شد. فاکتورهای آزمایشی شامل دور آبیاری در چهار سطح (آبیاری بعد از 5 ، 10، 15 و 20 روز) و مصرف کود نیتروژنه در چهار سطح (صفر(شاهد)، 80، 160، 240 کیلوگرم در هکتار) بودند. تجزیه واریانس داده ها نشان داد اثر دور آبیاری بر کلیه صفات مورد بررسی معنی دار بود. بین سطوح کود نیتروژنه از لحاظ اثر بر کلیه صفات به غیر از وزن هزار دانه اختلاف معنی دار دیده شد، همچنین اثر متقابل دور آبیاری و سطوح نیتروژن نیز بر تعداد دانه در طبق، عملکرد دانه، درصد روغن، عملکرد روغن و درصد اسانس گل در معنی-دار بود. تیمار آبیاری بعد از 10 روز بالاترین تعداد دانه در طبق (22.91 دانه)، وزن هزار دانه (11.19 گرم) و عملکرد خشک گل (598.44 کیلوگرم در هکتار) را به خود اختصاص داد، همچنین بالاترین تعداد دانه در طبق (22.25 دانه)، وزن هزار دانه (10.52 گرم) و عملکرد خشک گل (575.12 کیلوگرم در هکتار) سطح 80 کیلوگرم در هکتار کود نیتروژنه اختصاص داشت. در بین تیمارهای اثر متقابل بیشترین تعداد دانه در طبق (24.33 عدد) عملکرد دانه (1133.3 کیلوگرم در هکتار)، عملکرد روغن (356.5 کیلوگرم درهکتار) و درصد اسانس گل (25 درصد) در تیمار دورآبیاری بعد از 10 روز و 80 کیلوگرم در هکتار کود نیتروژنه مشاهده شد. با توجه به محدویت آب در منطقه و همچنین جلوگیری از مشکلات زیست محیطی دور آبیاری بعد از 10 روز و مصرف 80 کیلوگرم کود نیتروژنه در منطقه قابل توصیه است.
    کلیدواژگان: تنش کم آبی، عصاره، گیاه دارویی، وزن خشک گل
  • امیر قلی زاده، حمید دهقانی*، مصطفی خدادادی صفحات 459-470
    گشنیز یکی از مهم ترین گیاهانی است که در صنایع دارویی استفاده می شود. به منظور بررسی تاثیر تنش خشکی بر خصوصیات مورفولوژیکی، فیزیولوژیکی و فیتوشیمیایی، نسل های F2 حاصل از تلاقی های یکطرفه شش توده بومی گشنیز شامل اصفهان، همدان، بوشهر، مازندران، مرکزی و البرز به همراه والدین مربوطه در مجموع 21 ژنوتیپ در سه شرایط متفاوت آبیاری (آبیاری نرمال، تنش ملایم و تنش شدید) به طور جداگانه در قالب طرح بلوک های کامل تصادفی با سه تکرار در هر آزمایش در سال زراعی 95-1394 در مزرعه دانشکده کشاورزی دانشگاه تربیت مدرس مورد ارزیابی قرار گرفتند. صفات اندازه گیری شده در این آزمایش شامل، ارتفاع گیاه، تعداد برگ، تعداد شاخه در گیاه، تعداد چتر در گیاه، تعداد چتر بارور در گیاه، تعداد میوه در گیاه، وزن هزار میوه، وزن میوه در گیاه یا عملکرد میوه، عملکرد بیولوژیک، محتوای اسانس میوه، عملکرد اسانس، محتوای کلروفیل، محتوای رطوبت نسبی و شاخص پایداری غشا یا نشت یونی بودند. نتایج تجزیه واریانس و مقایسه میانگین ها نشان داد که اثر تنش خشکی بر کلیه صفات مورد بررسی معنی دار بود. نتایج نشان داد که با افزایش تنش خشکی اکثر صفات مورد بررسی کاهش یافتند در حالی که محتوای اسانس به طور معنی داری افزایش یافت. بیشترین محتوای اسانس در شرایط تنش ملایم مشاهده شد. همچنین در این مطالعه از شاخص تحمل به تنش (STI) بعنوان مناسب ترین شاخص برای ارزیابی تحمل به خشکی ژنوتیپ های گشنیز استفاده شد. در بین ژنوتیپ های مورد بررسی، ژنوتیپ مازندران و تلاقی های حاصل از این ژنوتیپ (البرز مازندران، مر کزی مازندران، اصفهان مازندران، مازندران همدان و مازندران بوشهر) متحمل ترین ژنوتیپ ها به خشکی شناخته شدند. بر پایه نتایج این پژوهش، به نظر می رسد بتوان از این ژنوتیپ ها به عنوان منابع حاوی ژن های تحمل به خشکی برای اصلاح ژنوتیپ های با ظرفیت عملکرد اسانس و میوه بالا در مناطق خشک استفاده کرد.
    کلیدواژگان: شاخص تحمل به تنش، عملکرد اسانس، محتوای اسانس، محتوای رطوبت نسبی
  • معصومه نعیمی*، محمد صادق دهقانی، ابراهیم غلامعلی پور علمداری، حمید جباری صفحات 471-480
    به منظور بررسی تاثیر رژیم آبیاری و محلول پاشی کیتوزان بر برخی صفات کیفی و فیزیولوژیک بابونه آلمانی (Matricaria chamomilla L.)، پژوهشی به صورت فاکتوریل در قالب طرح پایه بلوک های کامل تصادفی با سه تکرار در سال زراعی 94-1393 در مزرعه تحقیقاتی دانشگاه گنبدکاووس اجرا شد. تیمارهای موردبررسی شامل آبیاری پس از 60 (شاهد) و 100 میلی متر تبخیر از تشتک تبخیر کلاس A (تنش کم آبی) و کیتوزان در پنج سطح شامل عدم مصرف کیتوزان (محلول پاشی با آب مقطر به عنوان تیمار شاهد، محلول پاشی با 125 میلی گرم در لیتر 60 روز پس از کاشت، محلول پاشی با 125 میلی گرم در لیتر 75 روز پس از کاشت، محلول پاشی با 250 میلی گرم در لیتر 60 روز پس از کاشت و محلول پاشی با 250 میلی گرم در لیتر 75 روز پس از کاشت بودند. نتایج نشان داد که در شرایط تنش کاربرد سطح دوم کیتوزان و در شرایط رطوبتی معمول، کاربرد سطح سوم کیتوزان منجر به افزایش درصد کامازولن، درصد و عملکرد اسانس گردید. محلول پاشی کیتوزان به مقدار 125 میلی گرم در لیتر 60 روز پس از کاشت، موجب افزایش فعالیت پراکسیداز، درصد کامازولن و عملکرد اسانس در شرایط تنش گردید. با توجه به اینکه محلول پاشی کیتوزان باعث افزایش مقدار متابولیت های ثانویه در بابونه آلمانی شد، بنابراین جهت افزایش فراورده های با ارزش دارویی در این گیاه، محلول پاشی کیتوزان حائز اهمیت است.
    کلیدواژگان: اسانس، پراکسیداز، تنش خشکی، کامازولن، کلروفیل
  • علی جلالوند*، بابک عندلیبی، افشین توکلی، پرویز مرادی صفحات 481-494
    به منظور بررسی اثرات سالیسیلیک اسید و سایکوسل بر تبادلات گازی گیاه دارویی بادرشبویه در شرایط تنش کم آبی پژوهشی در بهار سال های 1393 و 1394 در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه زنجان به اجرا درآمد. آزمایش به صورت اسپلیت پلات با دو عامل سطوح رطوبتی و تنظیم کننده های رشد در قالب طرح بلوک های کامل تصادفی با چهار تکرار اجرا شد. عامل اصلی سطوح رطوبتی در دو سطح بدون تنش (آبیاری کامل تا انتهای دوره رشد)، تنش کم آبی (آبیاری کامل تا قبل از شروع گلدهی و قطع آبیاری قبل از شروع گلدهی تا انتهای دوره رشد) اجرا شد. عامل فرعی سطوح مختلف سالیسیلیک اسید (800 و 1600 میکرومولار)، سایکوسل (600 و 1200 میکرومولار) و شاهد (محلول پاشی با آب مقطر) که قبل از گلدهی به صورت یک بار محلول پاشی اعمال شد. نتایج نشان داد که اثر متقابل مرحله نمونه برداری در سال در رطوبت در هورمون برای صفات غلظت CO2 زیر روزنه ای، تعرق، هدایت روزنه ای و کارایی مصرف آب فتوسنتزی در سطح احتمال یک درصد کاملا معنی دار گردید. غلظت CO2 زیر روزنه ای در مراحل شروع گلدهی، گلدهی کامل و انتهای گلدهی روندی افزایشی دارد اما میزان تعرق، هدایت روزنه ای، فتوسنتز و کارایی مصرف آب فتوسنتزی روندی کاهشی دارند. تیمار سایکوسل (600 میکرومولار) در مرحله انتهای گلدهی موجب افزایش غلظت CO2 زیر روزنه ای نسبت به سایر تیمارها شد. تیمار سالیسیلیک اسید (800 میکرومولار) موجب افزایش تعرق، هدایت روزنه ای و فتوسنتز نسبت به سایر تیمارها می شود. نتایج نشان داد که تیمار سالیسیلیک اسید می تواند از طریق کاهش آنزیم کلروفیلاز موجب افزایش کلروفیل شده و سرعت فتوسنتز را افزایش دهد و از طریق افزایش هدایت روزنه ای موجب افزایش تعرق شده و اثرات منفی ناشی از تنش خشکی را تعدیل می کند.
    کلیدواژگان: بادرشبی، تنش کم آبی، فتوسنتز، کارایی مصرف آب فتوسنتزی
  • رقیه رئیسی، براتعلی فاخری، نفیسه مهدی نژاد* صفحات 495-505
    به منظور بررسی اثر قارچ میکوریزا بر برخی خصوصیات مورفولوژیک، رنگیزه های نورساختی و ویژگی های آنتی اکسیدانی گیاه کاسنی تحت تنش خشکی آزمایشی به صورت فاکتوریل در قالب طرح کاملا تصادفی با سه تکرار در گلخانه پژوهشکده کشاورزی دانشگاه زابل انجام شد. عوامل آزمایشی شامل تنش خشکی در چهار سطح 90، 70، 50 و 30 درصد ظرفیت زراعی به ترتیب به عنوان شاهد، تنش ملایم، تنش متوسط و تنش شدید و تیمار با قارچ میکوریزا در دو سطح تلقیح با قارچ میکوریزا و عدم تلقیح با قارچ میکوریزا بود. در این بررسی وزن تر و خشک اندام هوایی و ریشه، محتوای رنگیزه های فتوسنتزی و آنزیم کاتالاز، پلی فنل اکسیداز و گایاکول پراکسیداز مورد ارزیابی قرار گرفتند. نتایج نشان داد که بیشترین میزان وزن تر وخشک اندام هوایی متعلق به تنش 90 درصد و تلقیح با قارچ میکوریزا بود و بیشترین میزان کلروفیل a، b، کلروفیل کل و کارتنوئید متعلق به تنش 90 درصد و تلقیح با قارچ میکوریزا بود. حداکثر فعالیت آنزیم کاتالاز، پلی فنل اکسیداز و گایاکول پراکسیداز متعلق به تیمار تنش خشکی 30 درصد ظرفیت زراعی و تلقیح با قارچ میکوریزا و کمترین میزان آن در گیاه شاهد بود. از این آزمایش می توان نتیجه گرفت قارچ میکوریزا آربوسکولار به دلیل افزایش فعالیت آنزیم های آنتی اکسیدانی و افزایش رنگیزه های فتوسنتزی خطرات ناشی از تنش خشکی بر رشد و عملکرد گیاه کاسنی را کاهش می دهد.
    کلیدواژگان: آنزیم، خشکی، کاسنی، کلروفیل، میکوریزا
  • یوسف سهرابی*، وریا ویسانی، غلامرضا حیدری، خسرو محمدی، کاظم قاسمی گلعذانی صفحات 507-524
    به منظور بررسی تاثیر سطوح مختلف آبیاری و همچنین چند گونه از قارچ های آربوسکولار مایکوریزا بر رشد، عملکرد و اجزای عملکرد گیاه نخود (.Cicer arietinum L)، آزمایشی به صورت فاکتوریل در قالب طرح پایه کاملا تصادفی در سه تکرار اجرا گردید. فاکتور های آزمایشی شامل سه سطح آبیاری مطلوب، تنش متوسط و شدید خشکی، و استفاده از سه گونه قارچ مایکوریزا شامل (Glomus etunicatum، G. versiforme، G. intraradices) و عدم تلقیح (شاهد) بودند. نتایج به دست آمده نشان داد که تیمارهای آزمایشی، اثر معنی داری بر صفات مورد ارزیابی داشتند، به طوری که با کاهش میزان آب قابل دسترس گیاه، ارتفاع اولین شاخه گل دهنده، تعداد شاخه گل دهنده، وزن خشک ریشه، وزن خشک کل، وزن غلاف، تعداد غلاف در بوته، وزن هزار دانه و عملکرد دانه کاهش یافت. همچنین کاربرد گونه های قارچ مایکوریزا تاثیر معنی داری بر صفات مورد ارزیابی داشت. به طوری که هم در شرایط تنش خشکی و هم در شرایط بدون تنش، گیاهان تلقیح یافته با قارچ مایکوریزا از رشد و عملکرد بهتری در مقایسه با گیاهان تلقیح نشده برخوردار بودند. بنابراین می توان نتیجه گیری کرد که تلقیح نخود با قارچ مایکوریزا چه در شرایط تنش خشکی و چه در شرایط عدم تنش می تواند از طریق افزایش جذب آب و عناصر غذایی، سبب بهبود رشد، نمو و عملکرد گیاه نخود گردد و به عنوان راهکاری در جهت افزایش عملکرد، مد نظر قرار گیرد.
    کلیدواژگان: خصوصیات مرفولوژیک، سطوح آبیاری، گونه های گلوموس، نخود
  • زینب بش، عبدالرزاق دانش شهرکی*، مهدی قبادی نیا، کرامتاللهسعیدی صفحات 525-537
    به منظور بررسی تاثیر باکتری های محرک رشد گیاهی بر صفات آگرومورفولوژیک سیاهدانه تحت تنش کمبود آب آزمایشی به صورت کرت های خردشده در قالب طرح پایه بلوک های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه شهرکرد در سال زراعی 94- 1393 اجرا شد. فاکتورهای آزمایشی شامل سطوح مختلف تنش کمبود آب در سه سطح 100، 75 و 50 درصد نیاز آبی گیاه و باکتری های محرک رشد گیاهی در هفت سطح شاهد و تلقیح با شش گونه باکتریایی شامل Bacillus sp. Strain A، Bacillus amyloliquefaciens، Bacillus sp. Strain B، Azotobacter chroococcum، Pseudomonas putida و Azospirillum lipoferum بودند. با توجه به نتایج حاصل از تجزیه واریانس تاثیر سطوح تنش کمبود آب، تیمارهای باکتریایی و اثر متقابل آن ها بر تعداد دانه در کپسول، تعداد کپسول در بوته، وزن هزار دانه، عملکرد بیولوژیک، عملکرد دانه و شاخص برداشت معنی دار بود. نتایج نشان داد افزایش تنش کمبود آب سبب کاهش عملکرد و اجزای عملکرد دانه گردید؛ به طوری که افزایش تنش کمبود آب (تیمار 50 درصد نیاز آبی گیاه) سبب کاهش 18 درصدی عملکرد بیولوژیک و 28 درصدی عملکرد دانه شد. نتایج به دست آمده از اثر متقابل سطوح تنش کمبود آب و کاربرد باکتری های محرک رشد گیاهی نشان داد، کاربرد باکتری Bacillus amyloliquefaciensتحت تیمار 100 درصد نیاز آبی گیاه بیشترین میزان عملکرد بیولوژیک و عملکرد دانه را به خود اختصاص داد که نسبت به تیمار شاهد (عدم تلقیح باکتریایی) به ترتیب به میزان 8/24 و 2/35 درصد افزایش یافتند‎. تلقیح بذرها با باکتری های محرک رشد گیاهی سبب افزایش عملکرد و اجزای عملکرد سیاهدانه در مقایسه با شاهد (عدم تلقیح) در دو سطح تنش (75 و 50 درصد نیاز آبی گیاه) گردید. این افزایش در تیمارهای تلقیح شده با باکتری های Bacillus amyloliquefaciens و Bacillus sp. Strain B چشمگیر تر بود. درمجموع با توجه به نتایج این پژوهش، تلقیح باکتریایی بذر با باکتری های Bacillus amyloliquefaciens و Bacillus sp. Strain B به ویژه در روش های کشت کم آبیاری جهت کاهش اثرات تنش توصیه می گردد.
    کلیدواژگان: باسیلوس، تنش خشکی، کشاورزی پایدار، کودهای بیولوژیک
  • ایوب مزارعی، سیدمحسن موسوی نیک، احمد قنبری، لیلا فهمیده* صفحات 539-553
    یکی از راه های مقابله با اثر مخرب خشکی استفاده از تکنولوژی های به روز و مدرنی چون علم نانو است. این آزمایش به منظور بررسی اثر محلول پاشی نانو دی اکسید تیتانیوم بر برخی خصوصیات فیزیولوژی و فعالیت ترکیبات آنتی اکسیدانی مریم گلی تحت تنش خشکی انجام شد. این تحقیق در سال 1395 به صورت فاکتوریل در قالب طرح کاملا تصادفی در سه تکرار انجام شد. تیمارهای آزمایشی شامل تنش خشکی (آبیاری در حد ظرفیت زراعی، تخلیه 50 و 75 درصد رطوبت ظرفیت زراعی) و محلول پاشی با نانو دی اکسید تیتانیوم (صفر (شاهد)، 50 و 100 میلی گرم در لیتر) بود. بر اساس نتایج حاصله، بالاترین مقدار ماده خشک (6.67 گرم) و کلروفیل a، b و کل برگ (به ترتیب 2.45، 2.08 و 4.62 میلی گرم بر وزن تر) در گیاهان محلول پاشی شده با 100 میلی گرم در لیتر نانو دی اکسید تیتانیوم به دست آمد و بیشترین غلظت پرولین (15/5 میلی گرم بر وزن تر) و فعالیت ترکیبات آنتی اکسیدانی شامل: مقدار فنل کل (14.49 میلی گرم بر وزن تر)، آنزیم های پراکسیداز (4.48 میلی گرم بر وزن تر)، آسکوربات پراکسیداز (0.60 میلی گرم بر وزن تر)، گایاکول پراکسیداز (0.60 میلی گرم بر وزن تر)، سوپراکسید دیسموتاز (5.53 میلی گرم بر وزن تر) و کاتالاز (5.65 میلی گرم بر وزن تر) در گیاهان آبیاری شده پس از تخلیه 75 درصد رطوبت ظرفیت زراعی و محلول پاشی شده با غلظت 100 میلی گرم در لیتر نانو تیتانیوم حاصل شد. بر اساس نتایج به دست آمده می توان بیان کرد که نانو دی اکسید تیتانیوم به دلیل اندازه کوچک ذرات و امکان نفوذ راحت تر به برگ می تواند بر برخی ویژگی های رشد مریم گلی موثر باشد.
    کلیدواژگان: ترکیبات آنتی اکسیدانی، رنگیزه های فتوسنتزی، گیاه دارویی، نانوذرات
  • منصوره قوام* صفحات 555-566
    در سراسر دنیا یکی از مهم ترین عوامل غیرزیستی و محدودکننده جوانه زنی و همچنین رشد اولیه گیاهچه ها، تنش خشکی است. جوانه زنی به شدت تحت تاثیر عوامل محیطی به خصوص رطوبت قرار می گیرد. پژوهش حاضر با هدف بررسی اثرات نانو ذرات نقره بر شاخص های جوانه زنی دو گونه آویشن دنایی (Thymus daenensis Celak) و آویشن باغی (Thymus vulgaris L.) به صورت فاکتوریل و در قالب طرح کاملا تصادفی با سه عامل (گونه و نانو ذرات نقره و سطوح خشکی) در 4 تکرار به اجرا در آمد. تیمارهای خشکی در چهار سطح (0، 0.3-، 0.6- و 0.9- مگاپاسکال) و تیمارهای نانو ذرات نقره با چهار غلظت (0، 10، 20 و 30 میلی گرم در لیتر) در نظر گرفته شدند. نتایج نشان داد برهمکنش گونه، تنش خشکی و نانو ذرات بر سرعت جوانه زنی و طول ساقه چه در سطح احتمال 5 درصد معنی دار بود. بالاترین درصد جوانه زنی در هر دو گونه در تیمار شاهد بود و با افزایش تنش خشکی، درصد جوانه زنی، سرعت جوانه زنی و بنیه بذر در هر دو گونه کاهش یافت. آویشن دنایی نسبت به گونه آویشن باغی از سرعت جوانه زنی بالا تری برخوردار بود. ازنظر طول ریشه چه، گیاهچه های آویشن باغی در مقایسه با آویشن دنایی طول ریشه چه بیشتری در سطح خشکی کم داشتند. از سوی دیگر کاربرد نانو ذرات نقره در شرایط عدم تنش خشکی در آویشن باغی موجب روند افزایشی طول ریشه چه شد؛ لیکن در گونه آویشن دنایی این روند مشاهده نشد. به طورکلی نانو ذرات نقره بر تمام صفات به استثناء طول ساقه چه، فقط تا سطح خشکی 0.3- مگاپاسکال تاثیر بهبوددهندگی گذاشت و تیمار 30 میلی گرم در لیتر آن بهترین نتیجه را دربر داشت.
    کلیدواژگان: نعناعیان، بذر، بنیه، سرعت جوانه زنی
  • حمد دریس، سیدکیوان مرعشی* صفحات 561-571
    با توجه به اهمیت گیاه گندم در تغذیه انسان و همچنین تاثیر تنش شوری در اراضی زهکشی نشده، بررسی اثر تنش شوری و نقش اسید سالیسیلیک در تعدیل اثرات آن در کشت گندم حائز اهمیت است. لذا این پژوهش با هدف بررسی و مقایسه اثر روش های مختلف کاربرد هورمون اسید سالیسیلیک بر ویژگی های کمی، کیفی و بیوشیمیایی گندم در زمین های زهکشی شده و زهکشی نشده به صورت تجزیه مرکب در قالب طرح بلوک های کامل تصادفی در سه تکرار اجرا شد. تیمارها شامل زمین های زراعی زهکشی شده (آزمایش اول) و زهکشی نشده (آزمایش دوم) و عامل دوم شامل روش های کاربرد اسید سالیسیلیک به صورت (1) عدم محلول پاشی (شاهد)، (2) تلقیح بذر با اسید سالیسیلیک، (3) محلول پاشی در ابتدای پنجه دهی، (4) تلقیح بذر با اسید سالیسیلیک + محلول پاشی در ابتدای پنجه دهی، (5) محلول پاشی در مرحله انتهای پنجه دهی، (6) تلقیح بذر با اسید سالیسیلیک + محلول پاشی در مرحله انتهای پنجه دهی. نتایج نشان داد که تاثیر نوع اراضی مورد کشت بر تعداد سنبله در متر مربع، تعداد دانه در سنبله، تعداد سنبلچه در سنبله، وزن هزار دانه، عملکرد دانه، شاخص کلروفیل، پرولین و درصد پروتئین دانه در سطح احتمال یک درصد معنی دار بود. تاثیر سطوح اسید سالیسیلیک در تمامی صفات اندازه گیری در سطح احتمال یک درصد معنی دار بود. اثر متقابل نوع زمین و روش کاربرد سالیسیلیک ازنظر درصد پروتئین در سطح احتمال پنج درصد و ازنظر تعداد سنبله در متر مربع، تعداد سنبلچه در سنبله، وزن هزار دانه، شاخص کلروفیل و مقدار پرولین در سطح احتمال یک درصد معنی دار بود. بیشترین و کمترین عملکرد دانه در اراضی زهکشی شده و زهکشی نشده به ترتیب با 3308 و 2017 کیلوگرم در هکتار مشاهده شد و در بین روش های مختلف کاربرد اسید سالیسیلیک، بیشترین و کمترین عملکرد دانه در روش تلقیح بذر با اسید سالیسیلیک + محلول پاشی در ابتدای پنجه دهی و بدون کاربرد اسید سالیسیلیک به ترتیب با 3636 و 1759 کیلوگرم در هکتار حاصل شد. نتایج کلی آزمایش نشان داد که تاثیر اسید سالیسیلیک در اراضی زهکشی شده با افزایش مولفه های تولیدی و در اراضی زهکشی نشده با کم کردن اثرات تنش شوری و بهبود آسیب های ناشی از آن توانست در جهت افزایش عملکرد کمی موثر واقع شود. این در حالی است که در این شرایط کمترین عملکرد ازلحاظ کیفی حاصل شد.
    کلیدواژگان: تنش شوری، خیساندن بذر، عملکرد، گندم، محلول پاشی
  • ماریه سادات میرفاضلی*، غلامعباس اکبری، حسینعلی رامشینی صفحات 567-578
    تحمل به تنش ها در مراحل اولیه ی نمو گیاهان بسیار حائز اهمیت بوده و بذوری که توانایی جوانه زنی در شرایط تنش را داشته باشند، استقرار موفق، تراکم مناسب و عملکرد بالایی خواهند داشت. این پژوهش با هدف شناسایی توده‏های متحمل ریحان (Osimum basilicum L.) به تنش شوری و خشکی در مرحله سبز‏شدن صورت گرفت. این آزمایش به صورت فاکتوریل بر پایه طرح بلوک‏های کامل تصادفی انجام شد. تیمارها عبارت بودند از ترکیب دو عامل توده (20 توده) و محیط (سه سطح) که شامل محیط شاهد، شوری و خشکی بودند. سبزشدن بذر‏ها به صورت روزانه ثبت گردید. نتایج نشان داد که در مجموع صفات اندازه گیری شده، توده های Esfahan2 و Shiraz در شرایط محیطی شاهد (87 و 89 درصد)، توده‏های Esfahan2، Esfahan3 و Birjand در شرایط خشکی (55، 50 و 43 درصد) و توده‏های Pishva و Zahedan در شرایط شوری (57 و 53 درصد) سبز شدن و استقرار بهتری نسبت به سایر توده‏ها داشتند. در این تحقیق واریانس ژنوتیپی و فنوتیپی، ضریب تنوع ژنوتیپی و فنوتیپی و توارث پذیری عمومی برای صفات مورد ارزیابی محاسبه شد. نتایج نشان داد تنوع زیادی در تحمل توده‏ های مختلف به شوری و خشکی وجود دارد که از این تنوع می‏توان برای اصلاح ارقام جدید ریحان متحمل به شوری و خشکی استفاده کرد.
    کلیدواژگان: استقرار، تنوع ژنتیکی، توارث پذیری عمومی، سرعت سبزشدن
  • محمد جواد بابایی زارچ، سهراب محمودی*، سیدوحید اسلامی، غلام رضا زمانی صفحات 573-583
    به منظور ارزیابی رقابت تاج خروس سفید، خرفه و ارزن معمولی تحت تنش شوری خاک آزمایشی به صورت فاکتوریل در قالب طرح پایه بلوک های کامل تصادفی با سه تکرار اجرا شد. تیمار های آزمایش شامل دو سطح تنش شوری خاک (3 و 10 دسی زیمنس بر متر)، نسبت های مختلف تداخل علف هرز های با ارزن معمولی (تاج خروس سفید-خرفه-ارزن) شامل (0-0-100، 0-25-75، 12.5-12.5-75، و 25-0-75، 50-0-50، 25-25-50، 0-50-50، 75-0-25، 37.5-37.5-25، 0-75-25، 0-100-0 و 50-50-0 و 100-0-0 درصد) بود. تراکم مورد نظر در هر گلدان ثابت و برابر با 8 بوته بود. در انتهای آزمایش، از هر گلدان کلیه بوته برای هر گیاه انتخاب و به صورت جداگانه برداشت شد و پس از خشک کردن و با دقت توزین شدند. در نهایت برای تحلیل نتایج آزمایش از شاخص های عملکرد نسبی، عملکرد نسبی کل (نسبت برابری زمین) و شاخص تهاجم نسبی و شاخص غالبیت استفاده شد. نتایج نشان داد که با افزایش شوری خاک از 3 به 10 دسی زیمنس بر متر ماده خشک تولیدی ارزن معمولی، تاج خروس سفید و خرفه به ترتیب 19.5، 4.7 و 27.8 درصد کاهش یافت. همچنین نتایج نشان داد که در شرایط شوری 3 و 10 دسی-زیمنس بر متر ارزن معمولی از قدرت رقابی بیشتری نسبت به دو علف هرز دیگر برخوردار بود است، اما با افزایش تنش شوری از قدرت رقابتی ارزن معمولی کاسته می گردد و بر قدرت رقابتی علف های هرز افزوده می شود. بنابراین در تراکم های بالای علف های هرز به خصوص خرفه انتظار خسارت زیاد را در تحت تنش شوری می توان انتظار داشت.
    کلیدواژگان: رقابت برون گونه ای، شاخص غالبیت، قدرت رقابتی، ماده خشک، غلات
  • وحید اطلسی پاک*، امید بهمنی صفحات 579-588
    به منظور بررسی اثرات دفع سدیم بر مقدار کلروفیل و تولید ماده خشک، سه رقم گندم نان (کویر، مهدوی و تجن) متفاوت ازلحاظ تحمل شوری و تجمع سدیم در دو سطح شوری صفر و 150 میلی مولار در شرایط هیدروپونیک در گلخانه در سال 1395 کشت شدند. شوری سبب کاهش عملکرد دانه، وزن خشک اندام هوایی، نسبت پتاسیم به سدیم اندام هوایی و مقدار کلروفیل و نیز افزایش مقدار سدیم اندام هوایی در مقایسه با شاهد شد. پتاسیم اندام هوایی در این آزمایش تحت تاثیر شوری قرار نگرفت. تحت تنش شوری غلظت سدیم اندام هوایی در رقم کویر بیشتر از مهدوی و تجن بوده و ارتباطی بین دفع سدیم و میزان تحمل به شوری در این ارقام مشاهده نشد. میزان سدیم اندام هوایی در رقم مهدوی پایین تر از دو رقم دیگر بود. مقدار کلروفیل تحت تنش شوری 150 میلی مولار، بیشترین کاهش را در رقم تجن و به مقدار 75 درصد از خود نشان داد. علی رغم مقدار بیشتر کلروفیل در رقم کویر، کاهش عملکرد (40 درصد) و وزن خشک اندام هوایی (37 درصد) در هر سه رقم به طور تقریبا یکسان اتفاق افتاد. نتایج نشان داد رقم کویر بیشترین توانایی را در تحمل غلظت های بالای سدیم در برگ ها از خود نشان داد. غلظت سدیم اندام هوایی در ارقام مختلف تحت تنش شوری متفاوت بوده درصورتی که کاهش عملکرد دانه و وزن خشک اندام هوایی به نسبت تقریبا یکسان کاهش یافت؛ بنابراین به نظر می رسد اثر عمده شوری بر وزن خشک اندام هوایی و عملکرد عمدتا به دلیل اثرات اسمزی املاح باشد نه به دلیل اثرات ویژه یونی در گیاه.
    کلیدواژگان: اثرات اسمزی، عملکرد، دفع سدیم، وزن خشک اندام هوایی
  • مجید قنبری*، علی مختصی بیدگلی، پرنیان طالبی سیه سران، حسن پیرانی صفحات 585-594
    جوانه زنی و سبز شدن سریع بذر، یک عامل مهم و تعیین کننده در عملکرد نهایی گیاهان است. این تحقیق با هدف بررسی اثر پیری بذر بر ویژگی های جوانه زنی لوبیا، رقم صدری تحت تاثیر تنش شوری به صورت آزمایش فاکتوریل، بر پایه طرح کاملا تصادفی با چهار تکرار در سال 1395 انجام شد. تیمارهای آزمایشی شامل پیری بذر در چهار سطح شاهد، 24، 48 و 72 ساعت با استفاده از آزمون پیری تسریع شده و تنش شوری در پنج سطح، صفر (آب مقطر)، 2، 4، 6 و 8 دسی زیمنس بر متر از منبع سدیم کلراید بود. نتایج این آزمایش نشان داد که کمترین متوسط زمان جوانه زنی و بیشترین درصد جوانه زنی و وزن خشک ریشه چه و ساقه چه در تیمار 24 ساعت پیری بذر و تیمار آب مقطر (شاهد) به دست آمد. همچنین بیشترین میزان ضریب آلومتریک، بنیه بذر و فعالیت آنزیم های آلفا و بتا آمیلاز نیز در تیمار 24 ساعت پیری و تیمار شاهد شوری مشاهده گردید. به طورکلی، در طی فرآیند پیری تسریع شده با گذشت زمان کیفیت، بنیه و قدرت بذر و به دنبال آن ظرفیت و سرعت جوانه زنی برای زنده ماندن بذر کاهش یافت. به طورکلی، افزایش دوره پیری و افزایش سطوح تنش شوری از طریق تجمع انواع گونه های اکسیژن فعال در سلول و آسیب رساندن به لیپیدهای غشا، پروتئین ها و اسیدهای نوکلئیک بر جوانه زنی و شاخص های مرتبط با آن و فعالیت آنزیم های جوانه زنی در بذر گیاه لوبیا، تاثیر منفی گذاشته و درنهایت موجب افت شاخص های جوانه زنی گردید.
    کلیدواژگان: رقم صدری، زوال، سدیم کلراید، فعالیت آنزیمی، مورفولوژی گیاهچه
  • محمدحسین صابری، الیاس آرزمجو*، اشکبوس امینی صفحات 589-599
    تنش شوری در بسیاری از نقاط جهان خطری جدی برای رشد گیاهان و تولید محصولات زراعی به شمار می رود. به منظور بررسی اثر تنش شوری بر عملکرد، اجزای عملکرد، صفات مورفولوژیک، جذب عناصر غذایی سدیم و پتاسیم و همچنین شاخص های تحمل و حساسیت به تنش در هشت رقم و لاین امیدبخش گندم، دو آزمایش مجزا در قالب طرح بلوک های کامل تصادفی با سه تکرار در دو شرایط تنش و نرمال در مرکز تحقیقات کشاورزی خراسان جنوبی طی سال زراعی 91-1390 به اجرا درآمد. در این آزمایش تعداد چهارلاین امیدبخش MS-88-8، MS-88-16، MS-88-17 و MS-87-8 همراه با چهار رقم متحمل به شوری افق، ارگ، بم و کویر مورد مقایسه قرار گرفتند. نتایج نشان داد که شوری موجب کاهش معنی دار تمامی صفات مورفولوژیک گردید و در این میان بیشترین تاثیر را بر ارتفاع بوته داشت. شوری بر تعداد دانه در سنبله، وزن هزار دانه، سدیم، پتاسیم و نسبت سدیم به پتاسیم اندام هوایی اثر معنی داری نداشت. زیست توده و عملکرد دانه در شرایط تنش، به ترتیب 38.2 و 44.5 درصد نسبت به شرایط نرمال کاهش نشان دادند. لاین MS-87-8 و رقم افق به ترتیب با عملکرد دانه 4.02 و 3.72 تن در هکتار از بقیه شاهدها برتر و در سطح شاهد ارگ بودند. بهترین شاخص ها نیز برای گزینش ارقام متحمل به شوری، شاخص های HARM، STI و GMP بودند که بر اساس آن ها، رقم ارگ و پس از آن لاین MS-87-8 متحمل شناسایی شدند.
    کلیدواژگان: پراکنش سه بعدی، سطح برگ پرچم، شاخص برداشت، غلظت عناصر غذایی
  • لیلا مهدیزاده، محمد مقدم*، امیر لکزیان صفحات 595-606
    شوری یکی از تنش های محیطی است که سبب اختلال در جذب یون های ضروری و درنتیجه محدودیت در رشد گیاهان می شود. کاهش رشد یک نوع سازگاری برای زنده ماندن گیاه در شرایط تنش است.در سالیان اخیر ماده آلی بیوچار به دلیل کاربرد آن در اصلاح خاک بسیار موردتوجه قرار گرفته است. به منظور بررسی تاثیر بیوچار بر خصوصیات رشدی، غلظت سدیم و پتاسیم گیاه مرزه تابستانه (Satureja hortensis L.) آزمایشی گلدانی به صورت فاکتوریل در قالب طرح کاملا تصادفی با چهار تکرار در گلخانه گروه باغبانی دانشکده کشاورزی دانشگاه فردوسی مشهد در سال 1396 اجرا شد. فاکتورهای آزمایش شامل ماده آلی بیوچار در سه سطح (0، 1 و 2 درصد وزنی خاک هر گلدان) و آبیاری با آب شور در 3 سطح شوری (0، 40، 80 میلی مولار کلرید سدیم) بود. نتایج حاصل از این تحقیق نشان داد که اثرات متقابل شوری و کاربرد بیوچار بر خصوصیات رشدی موردمطالعه معنی دار بود. مقایسه میانگین داده ها نشان داد که بیشترین ارتفاع بوته، تعداد شاخه فرعی، تعداد گره، قطر ساقه، وزن تر و خشک ساقه، وزن تر و خشک برگ در تیمار کاربرد 2 درصد بیوچار بدون شوری مشاهده شد. همچنین با افزایش غلظت نمک، میزان سدیم برگ مرزه افزایش یافت و از میزان پتاسیم و نسبت پتاسیم به سدیم آن کاسته شد. به طورکلی، شوری با اختلال در میزان جذب پتاسیم و کاهش نسبت پتاسیم به سدیم گیاه سبب کاهش صفات رشدی موردمطالعه در مرزه گردید و بیوچار با جذب یون های نمک سبب بهبود صفات رشدی مرزه تابستانه در تیمارهای شوری گردید.
    کلیدواژگان: آب شور، پیرولیز، تنش شوری، زغال کشاورزی، مدیریت خاک شور
  • هنا عبوده، محمدرضا مرادی تلاوت*، علی مشتطی، سیدهاشم موسوی صفحات 607-616
    به منظور مقایسه ارقام بهاره گلرنگ (Carthamus tinctorius L.) با استفاده از شاخص های تحمل و حساسیت به تنش گرمای آخر فصل در اهواز، آزمایشی در مزرعه پژوهشی دانشگاه کشاورزی و منابع طبیعی رامین خوزستان در سال زراعی 96-1395 به صورت کرت های یک بار خرد شده در قالب بلوک های کامل تصادفی با چهار تکرار انجام شد. فاکتورهای آزمایشی شامل چهار تاریخ کاشت (20 آبان، 11 آذر، 15 دی و 14 بهمن) در کرت های اصلی و پنج رقم گلرنگ (سینا، گلدشت، صفه، محلی اصفهان (کوسه) و فرامان) بود. نتایج نشان داد که ارقام مورد مقایسه از نظر صفت عملکرد دانه از لحاظ شاخص های حساسیت به تنش (SSI)، شاخص تحمل (TI)، میانگین بهره وری (MP)، میانگین هارمونیک (HM)، شاخص پایداری عملکرد (YSI)، میانگین هندسی (GMP)، شاخص تحمل تنش (STI)، شاخص خسارت تنش (SDI)، شاخص تحمل تنش تعدیل شده برای شرایط مناسب (MSTI1)، شاخص تحمل تنش تعدیل شده برای شرایط نامناسب (MSTI2) و شاخص درصد کاهش عملکرد (YRI) تفاوت معنی داری داشتند. با این حال اختلاف ارقام مورد بررسی از نظر شاخص رتبه بندی (RI) و شاخص عملکرد (YI) معنی دار نبود. در شاخص تحمل تنش (STI)، رقم گلدشت (0.335) بیشترین تحمل (کمترین حساسیت) و رقم محلی اصفهان (کوسه) با میانگین (0.157) کمترین تحمل (بیشترین حساسیت) نسبت به تنش گرمای آخر فصل خوزستان را داشتند. به طور کلی شاخص تحمل تنش (STI) نسبت به سایر شاخص های مورد بررسی، جهت شناسایی ارقام متحمل و حساس گلرنگ نسبت به تنش گرمای آخر فصل در خوزستان مناسب است.
    کلیدواژگان: تاریخ کاشت، دانه های روغنی، رقم، عملکرد دانه
  • فاطمه طالع فراهی، احمد غلامعلی زاده*، آرش همتی صفحات 617-630
    هدف از انجام این آزمایش بررسی تاثیر نحوه مصرف اسیدهیومیک های استخراجی از منابع متفاوت بر روی گیاه آفتابگردان در یک خاک آهکی می باشد. این آزمایش به صورت فاکتوریل در قالب طرح کاملا تصادفی و در سه تکرار بر روی گیاه آفتابگردان انجام شد. تیمارها شامل دو روش مصرف خاکی و محلول پاشی (هر دو روش در یک سطح و در غلظت 0.6 میلی گرم بر کیلوگرم (میلی گرم بر لیتر) منابع بکار رفته اند) و 5 منبع اسیدهیومیک (اسیدهیومیک استخراج شده از بیوچار 400 درجه (چوب درخت چنار)، بیوچار 200 درجه (چوب درخت چنار)، لجن (فاضلاب کارخانجات چوب و کاغذ)، کود دامی (گاوی) و شاهد) می باشد. اثرات متقابل محلول پاشی بیوچار 200درجه نشان می دهد که صفات تعداد برگ، پتاسیم، کلروفیل a و کل و وزن خشک نسبت به شاهد به ترتیب 61، 45، 62 و 64 درصد و1.4 برابر افزایش یافته اند و همچنین محلول پاشی بیوچار 400درجه نیز میزان کلروفیلb و کارتنویید را نسبت به شاهد به ترتیب 1.5 برابر و 50% افزایش داد. نتایج اثرات متقابل مصرف خاکی بیوچار 200درجه بر وزن تر نسبت به شاهد 75% افزایش و تیمار لجن بر طول ساقه و فسفر نسبت به شاهد به ترتیب 58% و 1.75 برابر افزایش نشان دادند و اثرات متقابل مصرف خاکی کود دامی نیز نسبت به شاهد وزن خاکستر گیاه را 3.22 برابر افزایش داد. به طورکلی، با توجه به نتایج، محلول پاشی اسیدهیومیک استخراجی از بیوچار 200درجه، بهترین تاثیر را در افزایش عملکرد و اجزاء آن داشت.
    کلیدواژگان: دانه های روغنی، کلروفیل، لجن، محلول پاشی، مواد هیومیکی
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  • Mehdi Zohdi Aghdam, Farokh Darvish Kojouri *, Mehdi Ghaffari, Asa Ebrahimi Pages 331-346
    Five CMS lines and four restorer lines (tester) were crossed in a line × tester scheme in order to analyze general and specific combining abilities and gene effects in sunflower for some agronomic traits. Hybrids were evaluated in a randomized complete block design, with three replications under optimum and limited water conditions in the Agriculture Research Station, Khoy, during 2015 and 2016 growing seasons. Plant height, head diameter, seeds per head, days to beginning of flowering, days to maturity, proline percent, protein percent, and Chlorophyll b were found to be controlled mainly by dominance effects. CMS lines AGK30 and testers RGHK25 and RGHK50 turned out to be the best general combiners for seed and oil yield. The highest positive and significant GCA for plant height, head diameter, and the number of seeds per head were achieved for RGHK25. The hybrid combination of AGK44 × RGHK56 showed high specific combining ability for seed and oil yield. In the study of general combining ability, the AGK110 line has a positive and consistent general combining ability, and AGK2 has a negative and significant general combining ability with catalase . In the test of the testers, the tester (RGHK50) had the highest GCA positive and meaningful drug tester (RGHK56), which had a significant negative and significant combining ability with catalase . In the study of hybrid hybrid combining ability (RGHK46 × AGK260), the highest positive and significant positive and significant hybrid confinement (RGHK46 × AGK44) had the highest SCA negative and significant levels. In the RGHK46 × AGK260 hybrid combinability study, the highest positive and significant positive and significant hybrid confinement (RGHK46 × AGK44) had the highest SCA negative and significant effect on catalase identity. The AGK44 line has the ability to combine publicly and positively with AGK110 capability. The general combining ability was negative and significant with SOD. In the test of the testers, the RGHK 56 tester had the highest GCA positive and significant mean of the RGHK25 tester, which had a negative and significant general combining ability with superoxide dismutase. In the study of hybrid hybrid combining ability (RGHK50 × AGK260), the highest positive and significant positive and significant positive combining ability (RGHK50 × AGK44) had the highest SCA negative and significant values for SOD. In explaining the traits, plant height, Number of seeds per head and percentage of proline under stress conditions played a more significant role. Plant height and number of seeds per head were controlled by both growth and dominance effects. also In the study of general combining ability, the highest GCA positive and significant values were related to the AGK30 line and the most general negative and significant general combining ability was AGK2 line (Table 4-14). In the test of the testers, the tester (RGHK 46) had the highest GCA positive The drug tester (RGHK25) had the most significant negative and significant general combining ability with proline). In the study of hybrid combining ability (RGHK46 × AGK2), the highest positive and significant positive and significant hybrid confinement (RGHK25 × AGK260) had the highest SCA negative and significant values .
    Keywords: General combining ability, Line, Specific combining ability, Tester
  • Halbibi Badirdast, Sayyed Yahya Salehi Lisar, Hossein Sabouri *, Ali Movafeghi, Ebrahim Gholamalipour Pages 347-363
    Introduction
    Rice is the staple food for approximately half of the world population. It is the basic food crop of Asia, providing over 30%-60 of the calories consumed in the region. Among abiotic stresses, drought is a major one, especially in arid and semi-arid areas. Evaluation of genotypes in drought stress conditions can increase our knowledge about the characteristics and traits that are effective in tolerance to water stress. Today, new graphical techniques are used to examine the effect of traits with respect to their interactions. One of these methods is GGE biplot. Although the GGE biplot was originally created to parse the data from multiple environments. However, this strategy, also, can be equally used for all types of 2-way data that assume an entry × tester structure. Considering the high water requirement of rice and lack of water resources the present study aims to investigate the relationship between traits and identify high yield tolerant genotypes in two conditions (flooding and drought) with 23 morphological traits in Gonbad-e-Kavous area designed.
    Materials and methods
    The materials used in this study, 263 genotypes of rice (Oryza sativa L.) were provided by IRRI (International Rice Research Institute) as a joint international project between the institute and Gonbad-e-Kavus University. The lines were evaluated in two separate experiments in the form of Latis design under normal conditions and drought stress in three replications. Each of 263 lines was cultivated in 2 meter and 25 centimeter meter square. 40 days after transplantation irrigation was cut and after 40 days, the subsequent irrigations were applied every 15 days. After complete sampling, the marginal effect was taken and 10 plants per line were harvested and transferred to the laboratory for measuring the traits. 23 morphological traits were measured and recorded according to the standard guidelines for evaluation of rice traits. The data obtained from this study was evaluated using SAS Ver.9.1 and GGE biplot (Yan, 2001) software.
    Results
    Due to the lack of significance between block changes in the Latis design, the data were analyzed using randomized complete blocks. The results of combined analysis of variance revealed that the effect of the environment, genotype and genotype × environment interaction were significant (p<0.01) for most measured traits. The biplot explained 41 and 46% of the total variation of standardized data for irrigated and rainfed (drought) conditions, respectively. Comparison of genotypes for the leaf rolling score showed that no strain was observed in non-stress conditions, but in drought stress conditions, leaf rolling score increased, depending on genotype susceptibility to drought stress. The highest rank (rank 7) belonged to genotypes 42, 44, 154, 194 and 199, and the lowest rank were genotypes 18, 63, 66, 77, 88, 98, 100, 102, 105, 107, 115, 167, 237, 310 and 312 respectively. The polygon view of Biplot from the interaction of genotypes in traits genotypes 118, 257, 88, 241, 289 and 154 introduced as an index genotypes for different traits in flood conditions. In drought stress conditions, numbers 63, 167, 201, 194, 199, 42 and 263 were identified as index genotypes. In both conditions, positive relationships were observed between traits. Comparison of genotypes based on plant yield with plant height and day to flowering showed that genotypes with higher grain yield had less flowering days and plant height. Therefore, it could be concluded that days to flowering and plant height had a negative correlation with grain yield.
    Conclusion
    The results of this study showed that drought stress increased leaf rolling, increased number of days to flowering and reduced the majority of traits, especially plant yield. According to the results of graphite biplot analysis irrigated conditions, genotype HHZ 10-DT5-LI1-LI1 had the highest yield and stability and IR13F402 genotype had the lowest grain yield. In drought stress conditions, HHZ 3-SAL4-Y1-Y1 genotype had the highest performance and the second highest stability, HHZ 18-Y3-Y1-Y1 genotype was the most stable. Both genotypes were tolerant genotype and IR 11L412 genotype kknown as susceptible genotype.
    Keywords: Agro-morphological traits, Biplot analysis, Drought stress, Rice
  • Hamid Dehghanzadeh * Pages 365-375
    Introduction
     Growth analysis has been widely used to study crop and cultivar response to environmental conditions. Crop production is governed by the interception of radiant energy and the efficiency of converting this energy to dry matter. Numerous studies have shown a reduction in the leaf area index, crop growth rate, net assimilation rate and grain yield under drought stress conditions. Water deficit has a significant reduction on net assimilation rate, crop growth rate, total dry matter and grail yield. This has been attributed to promote leaf senescence and leaf abscission. Also water deficit stress has a significant effect on the reduction of net assimilation rate. This has been attributed to the phenomena of stomata closer and respiration increase. The aim of this study was to evaluate the effects of drought stress on growth indices and grain yield of wheat cultivar.
    Materials and methods
    This study was carried out in Tiran province, Isfahan, Iran during 2013-2014, as a split plot design in randomized complete block design with four replications. The main plots considered drought stress (irrigation after 70, 90 and 110 mm cumulative evaporation from class A evaporation pan), and sub-plots considered three wheat cultivars (Sepahan, Ghods and Pishtazs). Irrigation regimes applied from elongation phase. Plant samples were taken from 0.1 m-2 of all subplots with 20 days intervals and plants green leaf area were measured and oven dried at 75°C for 48 h plants weight mean were determined. The grain yield was measured at harvesting date. Statistical analysis of data was performed using the MINITAB statistical software and figures were drawn using by Microsoft excel software.
    Results
    The leaf area index in the irrigation after 110 mm, and in the irrigation after 70 and 90 mm cumulative pan evaporation treatments, in about in about 160 and 195 days after planting increased respectively, and was kept up for about 35 and 45 days at its higher surface in 110 mm evaporation and 70 and 90 mm evaporation respectively, then began to decrease. Delay in irrigation to 110 mm, plant had the lowest mean leaf area index and maximum leaf area index. Irrigation regime had a significant effect on total dry matter and delay in irrigation to 110 mm cumulative evaporation, significantly reduced total dry matter. The trend of changes in the total dry matter was more similar to the leaf area index. The leaf area index will be decreased by increasing irrigation intervals and that the total dry matter can also be decreased by reduction in photosynthetic capacity. The trend of changes in the net assimilation rate showed that in the irrigation after 110 mm, the net assimilation rate itself increased in about 165 days after planting and was kept up for about 30 days at its higher surface and in irrigation after 70 mm and irrigation after 90 mm the net assimilation rate itself increased in about 165 days after planting and was kept up for about 50 days at its higher surface, then began to decrease because of the extra leaves shading and of less absorption of the light by the leaves placed at the lower parts of the canopy. The trend of changes in the crop growth rate in the irrigation after 110 mm had been significantly lower than the irrigation after 70 mm and the irrigation after 90 mm. The trend of changes in the crop growth rate was more similar to the leaf area index but less resemble to the net assimilation rate. Irrigation regime had a significant effect on grain yield. Irrigation after 70 and 90 mm cumulative evaporation did not differ significantly for grain yield. Delay in irrigation to 110 mm cumulative pan evaporation, significantly reduced grain yield. Genotypes had a significant difference in gain yield. The Pishtaz cultivar had the highest grain yield.
    Conclusion
    Result showed that irrigation after 70 and 90 mm cumulative evaporation did not differ significantly for leaf area index, net assimilation rate, crop growth rate and grain yield. Irrigation after 110 mm cumulative evaporation significantly reduced leaf area index, net assimilation rate, crop growth rate and grain yield. It was concluded that by irrigation wheat cultivar after 90mm cumulative pan evaporation, water could be saved by 22% with no significant loss in growth indices and grain yield under these conditions.
    Keywords: Crop growth rate, Leaf area index, Net assimilation rate, Total dry matter
  • Omran Parsapour, Abdolmahdi Bakhshandeh *, Mohammad Hossein Gharineh, Hasan Feisi, Mohammad Reza Moradi Telavat Pages 377-388
    Introduction
    Under water shortage, applying and adjusting of some elements concentration such assilicon (Si) can be used as a strategy to reducethe negative effects of stress on wheat(Triticum aestivum L.) growth and enhanced plant compatibility.Some of the studies showed that exogenousSi application increased crop resistance to environmental stresses such as drought (Ahmed et al., 2011; Maghsoudi and Emam, 2016). Likewise, macro and micro nano fertilizers application caused an increase in crop yield. Therefore, this study aimed to investigate the effect of foliar application of nano and bulk Si dioxide particles on yield and yield components of wheat and also to determine the contribution of different sources in grain yield formation.
    Materials and methods
    In order to investigate the effect of foliar application of silicon on yield and redistribution of wheat dry matter under drought stress conditions, a field experiment was conducted as split plots based on a randomized complete block design with four replications at Ramin Agriculture and Natural Resources University of Khuzestan. Drought stress periods included three levels of normal irrigation (full irrigation throughout growing season or control), drought stress from stem elongation to flowering and drought stress from flowering to maturity were considered as main plot and foliar application of silicon dioxide levels in seven levels including non-foliar application (control), application of nano and bulk particles of silicon dioxide in concentrations of 50, 100 and 150 mg L-1 were considered as subplots. Data analysis was performed using SAS software and GLM procedure, and means comparison was carried out using a protected LSD method at a 5% probability level.
    Results and discussion
    Drought stress from stem elongation to flowering reduced the number of fertile tillers, number of spikelets per spike and number of seeds per spike, thereby reducing seed yield by about 35% compared to full irrigation conditions. Drought stress in the grain filling period resulted in a 10% reduction in wheat 1000-grains weight. Silica foliar application slightly reduced the effect of drought stress on grain yield.Wheat grain yield was significantly higher than other spraying treatments with the application of concentration of 100 mg L-1 of nano silicon particles (61.71 g m-2) and 150 mg L-1 of bulk silicon particles (572.73 g m-2). The efficiency of redistribution of dry matter in drought stress conditions from stem elongation to flowering (18.46%) was significantly higher than non stress conditions (14.07%) or stress induced from flowering stage to end of growth period (13.75%) Regardless of Silica foliar application treatments, redistribution of dry matter under full irrigation conditions was about 11% less than that of drought stress. The highest percentage of redistribution of dry matter from wheat grain yield was related to foliar application with concentration of 100 mg L-1 of bulk silicon particles under drought stress from flowering to the end of the growth period.
    The contribution of current photosynthesis in grain filling in non-stress conditions (458.68 g m-2) was significantly higher than drought stress conditions from flowering stage to end of growth period (399.68 g m-2) and for this was also significantly more than that of the stress conditions from the stem elongation to flowering (261.98 g m-2). The contribution of current photosynthesis in grain filling in spray treatment with a concentration of 100 mg L-1 of nano silicon dioxide was the maximum (451.25 g m-2) and in control treatment was at least (311.11 g m-2).
    It seems that nano silicon particles application caused an increase in plant tolerance to drought stress due toincreasing water balance, photosynthetic efficiency, and seedling growth (Hattori et al., 2005).
    Conclusion
    In general, the present study showed that the presence of silicon and especially nano particles in drought stress has a significant role in improving yield and grain yield components of wheat as well as redistribution of dry matter. It seems that in order to reduce the negative effect of moisture stress during wheat growth season and increase grain yield and dry matter redistribution, application of 100 mg L-1of nanosilica particles is recommended.
    Keywords: Current photosynthesis, Redistribution efficiency, Redistribution of dry matter
  • Farshad Sorkhi *, Mojtaba Fateh Pages 389-399
    In order to investigate the effect of drought stress on leaf area index, photosynthesis rate, chlorophyll, stomatal conductance and proline content in bean cultivars, a factorial experiment was conducted in a randomized complete block design with four replications. Treatments included drought stress in three levels, complete irrigation (control), irrigation cut at two weeks after emergence and irrigation cut at flowering stage and two bean cultivars were Talash and Khomain. Leaf area index, chlorophyll a and b, photosynthesis rate and stomatal conduction were decreased due to drought stress but amount of proline was increased. By applying drought stress at flowering time and two weeks after emergence compared to full irrigation (control), leaf area index was 30.57 and 55.96 percent, content of chlorophyll a was 23.1 and 56.05 percent and the content of chlorophyll b was 13.67 and 30.76 percent, photosynthesis rate was 13.22 and 26.73 percent, stomatal conductance was 31.65 and 50.25 percent decreased, respectively and amount of proline increased by 51.11 and 88.14 percent respectively.The highest and the lowest leaf area index were in complete irrigation (control) and Talash cultivar with 5.29 and in irrigation cuttings in two weeks after emergence and Khomain cultivar with 2.08, respectively.The highest amounts of chlorophyll a and b belonged to complete irrigation (control) and Talash cultivar with 0.213 and 0.118 mg/g fresh leaf weight and the lowest amount of chlorophyll a and b was related to irrigation cut at two weeks after emergence and Khomain cultivar with 0.132 and 0.76 mg/g leaf fresh weight, respectively. Generally, the negative effect of drought stress on chlorophyll a was more than chlorophyll b. Drought stress significantly reduced the rate of photosynthesis in bean cultivars.This decrease was observed in irrigation cut at flowering stage and irrigation cut at two weeks after emergence in comparison full irrigation (control) in the cultivar of the Talash was 12.99 and 24.50 percent respectively and in Khomain cultivar was 13.56 and 29.19 percent respectively.Stomatal conductance in complete irrigation (control), irrigation cut at flowering stage and irrigation cut at two weeks after emergence in the Talash cultivar was 0.432, 0.321 and 0.223 mol/m2.s and Khomain cultivar was 0.365, 0.233 and 0.154 mol/m2.s, respectively.The results of mean comparison showed that drought stress in each of the stages of growth reduced stomatal conductance in both cultivars. However, the percentage reduction in Khomain was more than the Talash.The content of proline in complete irrigation (control), irrigation cut at flowering stage and irrigation cut at two weeks after emergence in the Talash cultivar was 1.47, 2.30 and 2.83 mg/g fresh weight and in Khomein cultivar was 1.24, 1.78 and 2.25 mg/g fresh weight, respectively. drought stress in both cultivars increased significantly in proline content. According to the results, bean varieties had no significant difference in leaf area index and chlorophyll b content. In drought stress condition, Talash cultivar compared with Khomain cultivar showed less decrease in stomatal conductance and leaf area index and more had chlorophyll content and photosynthesis rate and it is recommended to cultivate in areas with drought stress.
    Keywords: Bean, Chlorophyll, Drought, Leaf, Physiology
  • Ahmad Ghasemi *, Masoud Khazaei, Hamid Reza Fanaei Pages 401-413
    Introduction
    Due to limited water resources in warm and dry areas, achieving maximum yield involves a lot of water consumption, Therefore, one of the important goals in the production of crops In such areas, the minimum water is determined to produce maximum yield In such areas determine at least water is that to produce Maximum performance (Paknejad et al., 2009). Based on climatic data Simulated in Iran For the next 30 years, drought is expected (Khazanedari et al., 2009). Plants are disposable to stress in nature, Drought stress is one of the most important limiting factors such as growth and production of plants have led to a reduction of more than 50% Average production of more crops across the world (Lata et al., 2011). Determine the appropriate planting date for plants is very important and it is an important factor which Affected plant physiological and morphological characteristics (Khodabande, 2009). So the purpose of this research is the effects of planting date and drought stress on grain and forage yield and some of the agronomic traits on foxtail millet.
    Materials and methods
    This research was carried out in crop year 2013 and 2017 in Zahak Agricultural Research Station. The experiment was conducted as split plot in randomized complete block design with three replications. The experiment factors included, S1-50% moisture evacuation (as control), S2- irrigation after 65% moisture evacuation and S3-Irrigation after 80% moisture evacuation and planting dates in four levels D1-23 February, D2- 5 March, D3- 20 March and 4 April Was considered as a sub-plot. Each experimental plot was planted in 6 lines 50 cm distance between lines and 5 meters long. Density was used of 10 kg / ha. The test plotting humidity was measured by the TDR regularly. The number of tiller per plant, leaf number per plant, plant height, number of days to reach, panicle length, 1000 grain weight, grain yield and fresh and dry forage yield were recorded. The statistical software MSTATC was used for statistical calculation. The Duncan test was used at 5 percent probability level to distinguish the averages.
    Results and discussion
    The results of analysis of variance showed that Planting date, drought stress and interaction of planting date in drought stress had significant differences on number of tillers per plant, leaf number per plant, plant height, number of days to reach, panicle length, 1000 grain weight, chlorophyll and proline concentration grain yield, fresh and dry forages. The highest plant height (83.16 cm), tiller number (2.11), leaf length (22.72 cm), Panicle length (14.08 cm), 1000 kernel weight (3.27 gr), grain yield (1521 kg/ha), fresh and dry fodder yield whit average (25225 and 6608 kg / ha) respectively, concentration of chlorophyll (5.83 mg/g) on sowing date March 15th and the highest concentration of proline (70.85 mg / g) was obtained on April 15. In 50% moisture discharge were the highest plant height (87 cm), number of tillers (2.37), leaf length (24.45 cm), Pancicol length (14.93 cm), 1000 kernel weight (3.25 g), grain yield (1677. In interaction March 15 and 50% moisture evacuation were the highest height (100/16 cm), number of tillers (3.16), leaf length (29.83 cm), panicle length (18.08 cm), 1000-grain weight (3.46 gr), fresh and dry forage yield (35550 and 9111 kg/ ha).
    Conclusion
    According to the results, it can be stated that drought stress causing reduced production of grain and forage. But given the water shortage crisis in the country and the region, a slight reduction in yield on a scale with less water consumption should be put on the agenda of farmers. Planting of millet on sowing date on March 15 and 50% moisture discharge was caused the plant to be placed in the appropriate temperature conditions which can produce maximum yield. Finally, planting of the plant on March 15 and 50% moisture evacuation are recommended for maximum grain and forage millet yield.
    Keywords: Field capacity, Forage, Proline, Water dificiet
  • Mahmood Reza Tadayon *, Hedayatollah Karimzadeh Soureshjani Pages 415-427
    Introduction
    The production of crops especially cereals in Iran is a challenge due to the presence of arid and semi-arid climates. Zeolite application is one of approach to ameliorate the effect of water deficit on crops. High water absorption zeolite is able to absorb water in the soil to a maximum level and maintain it for a long time within its network. Regarding the problem of water deficit and the necessity of managing agricultural production in conditions of water deficit and the possibility of using millet as a premature and compatible plant with most regions of Iran, this experiment was conducted out to evaluation of the effect of deficit irrigation and zeolite application on Proso millet.
    Material and methods
    In order to study the influence of deficit irrigation and zeolite application on Proso millet, an experiment was conducted as strip block in randomized complete block design base, at Shahrekord University, in 2015. Irrigation regime gad four levels (supply of 100, 75, 50 and 25 percent of field capacity) and zeolite had three levels (0, 0.5 and 1 kg m-2). Plant water requirement was calculated by FAO Penman-Monteith equation. Irrigation regimes were applied at V4 stage (4th three foliate leaf has unfolded) and continued until the end of the growing season. Plant water requirement was calculated by FAO Penman-Monteith equation.
    Result
    Results showed that leaf area index (LAI) had sigmoidal pattern. The highest LAI (3.3) was recorded in 100%FC and one kg m-2 zeolite interaction. Also lowest LAI (1.1) was observed in 25% FC and 0 kg m-2 zeolite interaction. Results also showed that water deficit reduced dry matter accumulation but in each irrigation treatment increase of zeolite amount resulted in ameliorated the effect of deficit irrigation. Maximum and minimum of dry matter were recorded in 100% FC*1 kg m-2 zeolite and 25 % FC* 0 kg m-2 zeolite interactions respectively. The crop growth rate in all of the treatments increased until mid-growing season and then reduced. The deficit irrigation reduced membrane stability but zeolite application increased it. Membrane stability in 75, 50 and 25 percent of FC reduced by 23%, 66% and 57% respectively. Water deficit also reduced relative water content. RWC were reduced by 13%, 26% and 41% in 75, 50 and 25 percent of FC respectively. Stomatal conductance reduced by deficit irrigation but in each level of irrigation treatment the highest stomatal conductance was observed in 1 kg m-2 zeolite application condition. The grain yield of Proso millet was higher under 1 kg.m-2 zeolite application condition in all deficit irrigation treatments. The highest grain yield reduction compared to control treatment (100% FC and no zeolite application) was observed in 25% FC and no zeolite application condition.
    Conclusion
    Finally results showed that however zeolite application under 100% FC condition had little effect but under deficit irrigation condition, zeolite reduced the harmful effects of deficit irrigation on studied traits and in this context uses of 1 kg.m-2 zeolite is recommended.
    Keywords: Drought stress, Relative growth rate, Relative water content, Stomatal conductance
  • Hassan Ghasemian Ardestani, Mohsen Jahan *, Amir Hossein Shirani Rad Pages 429-443
    Introduction
    Oilseed rape is the most important breeding species in Brazil, and drought stress can affect its quality and yield. Water deficit is one of the most important factors limiting the growth and production of plants, and there is currently no practical way to increase the precipitations during the dry periods. Therefore, it seems that the best way to deal with drought is to use appropriate agronomic operations and to use cultivars with more tolerance to drought.
    Materials and Methods
    In order to evaluate the qualitative characteristics of selected varieties of rapeseed, a factorial split plot experiment was conducted in a randomized complete block design with three replications for two years (1963-1953) in Karaj. In this research, the growing season was carried out in two dates (autumn and winter) and irrigation at three levels (normal irrigation or control, irrigation from later flowering stage and irrigation from the eating stage to the next) as a factorial as main plots and spring varieties Rapeseed consisted of Jerry, Julius, Zafar, Ridge S 003, Hayola 4815 and Zabul 10 as sub plots. Statistical analysis of SAS Ver 9 was used for analysis of variance. The Duncan multi-domain test was used to compare the averages.
    Results and Discussion
    The results showed that palmitic acid in the second year had an increase of 8% compared to the first year. Among the seedlings, the highest average seedling planting season was allocated to 18.5%. Irrigation interruptions from post-harvest phases and discontinuation of irrigation from flowering stage resulted in 12 and 25% reduction of palmitic acid respectively. The results showed that the highest content of linolenic acid in the control treatments and RGS003 cultivars, irrigation cut off stage and Julius cultivar, and discontinuation of irrigation from flowering stage to Zafar cultivar, 6 and 76.7 percent respectively. The results showed that the highest mean linoleic acid was observed in control treatments, irrigation cut off from the jollowing stage and Julius cultivar, and irrigation cut from flowering stage to Heilah cultivar 4815, respectively, with mean 21.77, 19.66 and 17.68% respectively. . The results showed that in the control and irrigation intervals, the cultivar Julius with the levels of 66.29 and 64.16 percent showed the highest amount of oleic acid in the irrigation and after irrigation period, from the flowering stage to the Hyola 4815 cultivar with an average of 26.62%, the highest average. Effect of year, planting season, irrigation, year×irrigation, year×Planting season×irrigation, planting season×irrigation, cultivar, planting season×cultivar, irrigation×cultivar and planting season×irrigation×cultivar at 1% level and season effect×season Planting was also significant at 5% level on grain yield. Effect of year, planting season, irrigation, year×irrigation, year×Planting season×irrigation, planting season×irrigation, cultivar, planting season×cultivar, irrigation×cultivar and planting season×irrigation×cultivar at 1% level and season effect×season Planting at level of 5% and year effect and irrigation at 1% level were significant on seed yield.
    Conclusion
    The results of the evaluation of traits during the two years of the experiment showed that Jolvie and Hayola 4815 had the highest grain yield under irrigation conditions, and also the Hyola 4815 cultivar had a good adaptation to drought stress conditions. Therefore, the cultivars could be obtained due to grain yield and higher oil yield under both drought stress conditions and without stress; for planting in regions of the same experimental region (Karaj), the probability of occurrence of moisture stress in the late stages of growth, Recommended. Also, the planting date of autumn increased the quantitative values of rapeseed quality indices.
    Keywords: Drought stress, Linoleic acid, Palmitic acid, Rapeseed
  • Afsaneh Pirmani, Touraj Mir Mahmoodi *, Saman Yazdan Seta Pages 445-457
    Introduction
    Calendula (Calendula officinalis L.) which contains different types of phytochemicals including carbohydrates, fats, phenolic compounds, steroids, tripnoyids, tocopherols, carotenoids and quins that have beneficial effects on human health. Drought stress, caused by soil and atmospheric water deficiency, is one of the most significant environmental factors affecting plant growth and crop productivity in the majority of agricultural fields of the world. Nitrogen is one of the elements which its deficiency is noticeable in arid. semi-arid regions; because the amounts of organic matter which are the main source of nitrogen storage are very low in this region and in case of its existence, it decomposes immediately (Mengel, 2001). Nitrogen’s less or more availability to the plant causes some disorders in crop vital processes that may appear in the forms of abnormal growth and development, decrease in transpiration and even stunt in reproductive growth (Breemhaar, 1995).
    The purpose of this investigation was study effects of irrigation regims and nitrogen on yield and yield components, essential oil medicinal plant Calendula.
    Material and Methods
    In order to study effects of irrigation regimes and nitrogen on yield and yield components, essence oil medicinal plant Calendula an experiment was conducted at Urmia Agricultural Station of Saat Lo at 2016 crop season. Field experiment was carried out by a split plot design based on completely randomized block design with three replications.
    Treatments were four levels of irrigation levels (irrigation after 5, 10, 15 and 20 day) in main plots, and consumption of 0, 80, 160 and 240 kg/h nitrogen in sub plots. In this study, traits of number of heads per square meter, number of seeds per head, thousand kernel weight, biological yield, grain yield, oil percentage, oil yield and dry flower yield and flower essence were measured. Statistical analysis was performed based on the statistical model of the design used by SAS 9.2 software. Comparison of meanings of each trait was performed using SNK test at 5% probability level.
    Result and Discussion
    Analysis of variance showed that irrigation levels had significant effect on all understudied traits also there were significant differences between nitrogen fertilizer levels on all traits except of thousand kernel weight. Also the effect of irrigation levels × nitrogen levels on number of seeds per head, grain yield, oil percentage, oil yield and essential oil percentage were significant.
    Result showed, with increasing irrigation interval from 5 to 20 days, the number of heads per square meter, number of seeds per head, thousand kernel weight, grain yield, oil percentage, oil yield and dry flower yield decreased, and irrigation levels after 5 and 10 days were the highest values of the mentioned traits. In this research, irrigation level after 10 days had the highest number of seeds per head (22.91 grain), thousand kernel weight (11.19 g), dry flower yield (598.44 kg/h). Result revealed nitrogen fertilizer had positive effect on calendula growth characteristics
    Although the highest amount of number of seeds per head (22.25), thousand kernel weight (10.52 g) and dry flower yield (575.12 kg/h) belonged to level of 180 kg/h nitrogen fertilizer. Among irrigation levels × nitrogen levels interaction treatments the highest value of number of seeds per head, (24.43), grain yield (1133.3 kg/h), oil yield (356.3 kg/h) and essence percentage (25%) was belonged to 10 days with 80 kg/h nitrogen fertilizer.
    Conclusion
    According to the results of this study, it can be stated that nitrogen fertilizer application is effective when sufficient water is available to the plant, and increasing nitrogen levels when there wasn’t enough could have harmful effect on grain yield, oil percentage, oil yield and dry flower yield, oil percentage and flower essence in Calendula. Considering the limitations of water in the area as well as preventing environmental problems, irrigation intervals after 10 days and consumption of 80 kg nitrogen fertilizer in the region to achieve maximum qualitative and quantitative qualities in Calendula is recommended.
    Keywords: Dry flower yield, Essence, Medicinal plant, Water deficit stress
  • Amir Gholizadeh, Hamid Dehghani *, Mostafa Khodadadi Pages 459-470
    Introduction
    Coriander is an annual herb of the umbel family and is belonged from North Africa to south-western of Asia. Coriander is one of the important medicinal plant that used in the pharmaceutical industry and it mainly cultivated and widely distributed for the fruits. The dried fruits are widely employed as a condiment, especially for flavoring of sauces, meat products and bakery and confectionery items. Also, coriander fruits are as a source of essential oils and fatty oil. Water deficit stress is one of the most important factors limiting the growth and survival of plants in arid and semi-arid regions of the world. Water is a major component of the fresh produce and significantly effects on weight and quality of plants. Also, water deficit may cause significant changes in the yield and composition of essential oils in aromatic and medicine plants. So that, was reported that water deficit increased essential oil percentage in coriander but decreased essential oil yield. Iran with an average annual rainfall of 240 mm is included among arid and semi-arid regions of the world. Of the million hectares of cultivated region, only five millions are under irrigation because of intense water limitations. However, Iran is one of the world’s commercial coriander producers. Coriander has been cultivated for many years in different parts of Iran. Therefore, development of drought-tolerant cultivars with high essential oil yield is important in coriander. This research was conducted in order to evaluate the effect of drought stress on morphological, physiological and phytochemical characteristics of endemic coriander genotypes.
    Materials and Methods
    F2 generations derived from half-diallel crosses of six endemic coriander genotypes including Isfahan, Hamedan, Bushehr, Mazandaran, Markazi and Alborz, together with their parents were evaluated in randomized complete block design with three replications in each experiment during growing season of 2016 in the research field of Tarbiat Modares University. Plants were treated with different levels of water treatment: well watered (WW), moderate water stress (MWS) and severe water stress (SWS). Data were collected on plant height, leaf number, branch number per plant, umbel number per plant, fertile umbel number per plant, fruit number per plant, thousand fruit weight, fruit yield, biological yield, essential oil content, SPAD chlorophyll content, relative water content and electrolyte leakage.
    Results and Discussion
    The results of ANOVA and comparison of means indicated that the effect of drought stress was significant for all the studied characteristics. The results showed that by increasing drought stress the most studied traits decreased but the essential oil content significantly increased. The highest essential oil content was observed in moderate stress. Studies have, however, indicated that water stress have a number of positive effects on the biosynthesis of secondary metabolites such as essential oil content. Because in case of stress, more metabolites are produce in the plants and substances prevent from oxidization in the cells, but essential oil yield reduce under drought stress. This may because of the relationship between the amount of the essential oil and fruit yield that by progress in drought stress, increase in essential oil but decrease in fruit yield therefore essential oil yield is reduced. Also in the study was used of stress tolerance index (STI) as the best indicators for evaluating of tolerant to drought stress of coriander genotypes. The Mazandaran genotype and crosses derived from this genptype (Alborz Mazandaran, Markazi Mazandaran, Isfahan Mazandaran, Mazandaran Hamadan and Mazandaran Bushehr) were identified as drought tolerant genotypes.
    Conclusion
    Generally, the results indicated that drought stress decreased all studied traits. Whereas essential oil content was increased under drought stress conditions. Also, The Mazandaran genotype and crosses derived from this genptype (Alborz Mazandaran, Markazi Mazandaran, Isfahan Mazandaran, Mazandaran Hamadan and Mazandaran Bushehr) as drought tolerant genotypes can be considered as donor parent which contains drought tolerance genes and could be used to improve coriander high essential oil yield in drought condition.
    Acknowledgements: The authors thank from the Gene bank of the Seed and Plant Improvement Institute of Karaj, Iran for making available plant materials.
    Keywords: Essential oil, Essential oil yield, Relative water content, Stress tolerance index
  • Naeemi Masoumeh *, Mohammad Sadegh Dehghani, Ebrahim Ghilamali Pour Alamdari, Hamid Jabbari Pages 471-480
    In order to evaluate the effects of different irrigation regimes and foliar spraying of chitosan on some qualitative and physiological characteristics of German chamomile (Matricaria chamomilla L.), this study was conducted based on randomized complete blocks design with factorial arrangement of treatment and three replications in Gonbad Kavous university research field, in 2014 growing season. Treatments included irrigation in two levels, irrigation after 60 and 100 mm evaporation from class A pan, and chitosan in five levels including non spraying of chitosan (spraying with distilled water as control (K1)), chitosan spraying as 125 mg/L after 60 days of planting (K2), 125 mg/L after 75 days of planting (K3), 250 mg/L after 60 days of planting (K4) and 250 mg/L after 75 days of planting (K5). Results indicated that utilization of chitosan under stress and under normal irrigation regime increased present of chamazulene, essential oil percentage and essential oil yield. According to our results, chitosan spraying in 125 mg/L 60 days after planting date under deficit water stress conditions improved peroxidase activity, chamazulene percentage and essential oil yield. In general, in order to increase the valuable medicinal products in German chamomile, spray of chitosan, as a natural material is important.
    Keywords: Chamazulene, Chlorophyll, Drought stress, Essential oil, Peroxidase
  • Ali Jalalvand *, Babak Andalibi, Afshen Tavakoli, Parviz Moradi Pages 481-494
    Introduction
    The Moldavian balm is herbaceous that originated in middle Asia and about 66 compound are identified in this plant. Application of growth regulator lead to increases of plant resistance against biotic and abiotic stress and is involved as a strategy to prevents adverse effects of environmental stress. According to semi-sensitivity of dragonhead plant to drought condition, its medicinal importance as well as, its industrial widespread use, this study was conducted to evaluate dragonhead essential oil yield and its compound under drought condition and also, to evaluate physiological aspect of drought resistance.
    Material and methods
    In order to investigate the effects of salicylic acid and cycocel on the gas exchange on dragonhead in drought stress conditions a research was conducted in the spring of 2014 and 2015 at research farm of agricultural college, Zanjan University. The experiment was split plot with two factors of moisture levels and growth regulators in a randomized complete block design with four replications. The main factor is the moisture levels at two levels without stress (Complete irrigation until the end of the growth period), drought stress (Complete irrigation before start flowering and discontinuation of irrigation until the end of the growth period). Sub-substrate of different levels of salicylic acid (800 and 1600 μm), cycocel (600 and 1200 μm), and control (dissolve with distilled water), which applied for a single application time for 10 days before start flowering.
    Findings
    The results showed that the interactions of the sampling stage in the year in hormone in moisture for intercellular CO2 concentration, transpiration, stomatal conductance and photosynthesis water use efficiency at probability level of 1%, it was quite significant. Intercellular CO2 concentration at the start flowering, full flowering and the end of flowering has a growing trend. And the rate of transpiration, stomatal conductance, photosynthesis and photosynthesis water use efficiency are decreasing. Cycocel treatment (600 μm) at the end of flowering stage increased intercellular CO2 concentration compared to other treatments. Salicylic acid (800 μm) treatment increased transpiration, stomatal conduction and photosynthesis compared to other treatments.
    Conclusion
    The results of this study showed that with the application of drought stress, the gas exchange of the plant will change meaningfully. By closing the stomata, stomatal resistance increases and intercellular CO2 concentration increases and leads to a decrease in photosynthesis rate Reducing transpiration in drought stress is due to stomatal closure and stomatal conductance reduction. So that with intensity of draught stress, transpiration was decreased. The results showed that salicylic acid treatment can increase chlorophyll content by reducing the Chlorophyllase enzyme and increase the rate of photosynthesis and through increased stomatal conductance increases transpiration and it mitigates the negative effects of drought stress.The rate of photosynthesis had a decreasing trend from the start flowering, full flowering and flowering end. Salicylic acid treatment is likely to increase photosynthesis in the plant by increasing the leaf area, increasing chlorophyll content, preventing biosynthesis of ethylene and reducing the chlorophyllase enzyme. Cycocel treatments through increase stomatal resistance and stomatal conductance reduction, thereby reducing transpiration and decreasing the rate of photosynthesis, resulting in increased photosynthetic water use efficiency.
    Keywords: Dragonhead, Photosynthesis, Photosynthesis water use efficiency, Water stress
  • Roghayeh Raesi, Baratali Fakheri, Nafiseh Mahdinezhad * Pages 495-505
    Introduction
    Drought stress is one of the most important stresses that affects plant growth and yield (Redd et al., 2004). Drought stress results in the formation of reactive oxygen species by the partial regeneration of oxygen in the processes of photosynthesis and respiration by increasing the transfer of electrons to oxygen molecules (Asada, 1999), Plants have different mechanisms to reduce the harmful effects of activated oxygen species. In recent years, due to the changing weather conditions, drought stress has become more severe. Thus, the study of mechanisms that enable plants to adapt to drought stress can ultimately help to produce resistant plants in arid and semi-arid regions (Hassani et al., 2003). In addition to improvement of nutrition, the fungus symbiosis is able to reduce the negative effects of environmental stresses on host plant in various ways, such as increasing the levels of antioxidant enzymes and maintaining chlorophylls (Zarea, 2012). The negative effects of environmental stresses on host plants are reduced. In this study, the effect of mycorrhizal fungus on photosynthetic pigments and the characteristics of antioxidant enzymes of chicory under drought stress were investigated.
    Materials and Methods
    In order to study the effect of mycorrhizal fungus on photosynthetic pigments and the antioxidant specification of chicory under drought stress, the factorial experiment was conducted in a completely randomized design with three replications in a Greenhouse of Agricultural Research Center of Zabol University in 2016. Treatments were four levels of drought stress (control), 70, 50 and 30% of crop capacity and inoculation with mycorrhizal fungi at two levels of inoculation and uninoculation. Before planting, 50 g of mycorrhizal fungus was added to the soil of each pot. From the beginning of the fifth week, drought stress was applied to weights In the end, vegetative parameters including fresh and dry weight of root and shoot were measured. Arnon method (Arnon, 1976) was used to measure chlorophyll and carotenoid. The enzyme gyAgol peroxidase (Cam-mada and Nelson Shspra, 1999), the polyphenol oxidase enzyme (Janovitz-Klapp et al., 1990) and the measurement of the catalase enzyme by Beers and Sizer (1952) Made.  
    Results and Discussion
    The highest fresh and dry weights of shoot Plant in 90% stress and inoculated with Glomus Fascollaria fungus treatments were obtained and the least amount was obtained in drought stress 30% agronomic capacity and non inoculation with Glomus Fascollaria fungus (Table 2). The highest fresh and dry weights of roots were obtained in stress 90% and inoculation of Glomus Fascollaria fungi and its lowest in drought stress 30% of field capacity and non-inoculation with Glomus Fascollaria fungus (Table 2).The results showed that in the interaction of Glomus Fascollaria fungus treatments and drought stress, the highest levels of chlorophyll a, chlorophyll b, carotenoids and total chlorophyll were obtained in 90% stress (control) and inoculated with Glomus Fascollaria fungi and the lowest levels of chlorophyll a, chlorophyll b, carotenoids and Total chlorophyll was obtained in drought stress 30% of field capacity and uninoculation with Glomus Fascollaria fungus (Table 2). The highest effect of interaction between fungal treatments and drought stress in catalase, polyphenol oxidase and Guayaquil peroxidase enzymes was observed in drought stress 30% of field capacity and inoculation with fungi and its lowest level in 90% stress (control) and uninoculation with fungi Came. In corn plants, inoculation of Glomus Fascollaria fungi increased chlorophyll content, and attributed an increase in chlorophyll content to increased nitrogen uptake by the mycorrhizal system (Tang et al., 2009). It was reported that chlorophyll content in Citrus tangerine seedlings mixed with fungi under full irrigation conditions had a significant difference with chlorophyll content in non-fungal seedlings, and in drought stress conditions, chlorophyll content in plantlets containing fungi was higher than that of plants There was no fungus (Wu and Xia, 2006). In studies on zoo, the highest activity of catalase was found in leaves of plants inoculated with Glomus Fascollaria fungi under drought stress than uninoculated plants (Suleimani and Pirzad, 2016).Based on the results, with increasing drought stress, the amount of photosynthetic pigments, fresh and dry weight of the shoot and fresh weight and root crop decreased. Inoculation with Glomus fascollaria during drought stress reduced drought stress and increased photosynthetic pigmentation, fresh and dry weight gain of the shoot and increased fresh and dry weight of roots. The inoculation of chicory with Glomus fascollaria fungi under drought stress conditions by stimulating the activity of antioxidant enzymes such as catalase, polyphenol oxidase and guaiacol peroxidase prevents the oxidative effects of ROS. Thus, the use of mycorrhiza fungi improves the physiological function and plant tolerance Chicory was drought stressed
    Keywords: Chicory, Chlorophyll, Drought, Enzymes, Mycorrhiza
  • Yousef Sohrabi *, Weria Weisany, Gholamreza Heidari, Khosro Mohammadi, Kazem Ghasemi Golezani Pages 507-524
    In order to investigate the influence of drought stress and also arbuscular mycorrhiza (AM) fungi inoculation on growth, yield and yield components of chickpea (Cicer arietinum L.), a pot experiment was conducted using a factorial based on completely randomized blocks design with three replications. The factors were contained three levels of irrigation [satisfactory irrigation (100% irrigation), moderate irrigation (70% irrigation) and deficit irrigation (40% irrigation)] and mycorrhiza inoculation (non-inoculated and inoculated with Glomus etunicatum, Glomus versiforme, and Glomus intraradices). Results showed that drought stress had significant effects on evaluated characteristics. As with decrease of the available water of plant, height of the flowering branches, number of flowering in a branch, dry weight of root, total dry weight, weight of pod, number of pods per plant, grain weight and yield decreased. Also, AM fungi inoculation had significant effects on evaluated characteristics. Plants inoculated with AM fungi had higher growth, growth and yield than non-inoculated plants under drought stress and non-stress conditions. Thus, it could be concluded that at drought conditions AM fungi are able to enhance the growth and yield of chickpea under drought stress condition through enhancing nutrient and water uptake.
    Keywords: Chickpea, Glomus species, Irrigation levels, Morphological characteristics
  • Zeinab Bosh, Abdolrazagh Danesh Shahraki *, Mahdi Ghobadinia, Keramatollah Saeedi Pages 525-537
    Introduction
    Black cumin (Nigella sativa L.) as an annual medicinal plant which belongs to the Rununculaceae family is suitable for semi-arid regions. The researchers reported many medicinal properties for this plant such as bloating reduce, pain reduce, anorexia reduce and anti-cancer. Water is one of the most important environmental factors in plant growth that its reduction limiting crop yield. Drought stress can be effective on vegetative growth, flowering, pollination and fertilization, fruit formation and yield and reduces each of these factors. In recent years, the use of plant growth promoting rhizobacteria through different mechanisms against Salt and Drought Stresses can increase plant tolerance to environmental stresses. The aim of this study was to investigate the effect of plant growth promoting rhizobacteria on yield and yield components of Black cumin under water deficit stress
    Materials and methods
    To evaluate the effect of plant growth promoting rhizobacteria on agro-morphological traits of Black cumin under water deficit stress, an experiment was done during 2014-2015 growing season at the research field of the faculty of agricultural, Shahrekord University as split-plot factorial in a Randomized Complete Block Design with three replications. The main factor including water deficit in three levels (100, 75 and 50 present of water requirement) and the sub factor was PGPRs at seven levels (control, Bacillus sp. Strain A, Bacillus amyloliquefaciens, Bacillus sp. Strain B, Azotobacter chroococcum, Pseudomonas putida and Azopirillum lipoferum). The amount of irrigation water was calculated using plant water requirement. Before the final harvest, to measure traits, five plants were randomly taken from each plot and yield and yield components was recorded. SAS and Excel softwares implemented for statistical analysis and the means were compared using LSD test.
    Results and discussion
    The results showed that by increasing water deficit stress the amount of the number of branch, Plant height, seed number per capsule, the number of capsule per plant, 1000 seed weight, biological yield, grain yield and harvest index was decreased. So 50% of water requirement treatment cause to decrease 18.4, 28.4 and 12.3 percent in biological yield, grain yield and harvest index compared to 100% % of water requirement. the use of bacteria significantly improved all these traits compared to non-inoculated. Among the bacterial treatments the maximum and minimum seed number per capsule, 1000 seed weight, biological yield and grain yield obtained in Bacillus amyloliquefaciens treatment and non-inoculated, respectively. Also, the results indicated that the interaction effect between water deficit stress and bacteria inoculation, except the number of branch and Plant height, were significant on all of traits. B. amilolykofosins application under 100% water requirement treatment had the highest seed number per capsule, 1000 seed weight, biological yield and grain yield (increased by 38.7%, 17.13%, 24.8% and 35.2%, respectively) as compared to non-inoculated. So, plant growth promoting rhizobacteria by different mechanisms such as phosphate solubilization, dinitrogen fixation, ACC deaminase and antifungal activity, IAA and siderophore biosynthesis are responsible for the plant growth promotion and increased yield under different environmental stresses.
    Conclusions
    The results of this study showed that increasing water deficit stress causing significant reduction of all traits. However, the use of bacteria reduced the effects of stress and increased these traits compared to non-inoculated at all water deficit stress levels. Also among bacterial treatments, Bacillus amyloliquefaciens, Bacillus strain A and strain B had the most effect on stress improvement.
    Keywords: Bacillus, Bio-fertilizers, Drought stress, Sustainable Agriculture
  • Ayoub Mazarie, Seyed Mohsen Mousavi Nik, Ahmad Ghanbari, Leila Fahmideh * Pages 539-553
    Introduction
    The Salvia is a large genus with about 58 species from Lamiaceae family in Iran. It has been well-known in pharmacopeia that has been used with special attention in the ancient era. The Essential oils, terpenoids, derivatives of phenolics acids and flavonoids are the main secondary metabolite constituents in Salvia species. The Pharmaceutical properties of the Salvia plants are mainly due to antioxidant activities of their secondary metabolites. It has various applications in Pharmaceutical, foods, hygienic-cosmetics and perfume industries as well as utilized in beverages as flavor.
    The species of Salvia officinalis is a perennial medicinal herb from Lamiaceae family. The origin of salvia species has been reported in the northern Mediterranean and North Africa zones. The most important constituents of the essential oil are included: Tujan (30-50%), Cineol (10-15%), Camphor (6-10%) and Borneol (6 to 14%). Recently, it has been reported that the essential oil of the S. officinalis, especially some of its compounds, including Cineol, Tujan, Camphor, have an antimicrobial, antioxidant and anti-cancer properties. Drought is the most harmful factor of crops and medicinal plants production in the arid and semi-arid eras which has a negative impact on all aspects of plant growth and production. Also, in the plants exposed to severe soil dry the photosynthetic apparatus activities were damaged or impaired, leading to a decrease of photosynthetic capacity and lipid oxidation is increased in these conditions. Therefore, the use of mechanisms that lead to losses of this tension can be useful. One way to deal with the devastating effects of drought is the use of up to date and modern technologies such as Nano science.Nano-titanium dioxide has beneficial effects on the growth, physiological processes and activities of the plant metabolism.This study was to evaluate the effect of titanium dioxide spray on some physiological characteristics and activities of antioxidant enzymes sage was conducted under drought stress.
    Materials and methods
    This study was conducted in 2017 at the Faculty of Agriculture, University of Zabol a factorial in a completely randomized design with three replications. The experimental treatments was included drought stress (irrigated in Field capacity, depletion of soil water content up to 50% and 75% of FC condition) and foliar Nano Titanium dioxide spray (Control, 50 and 100 mg.l-1). Physiological traits (Chlorophyll a, b and T. chlorophyll, Total phenol, Proline) and activities of antioxidant enzymes (Peroxidase (POD), Ascorbate peroxidase (APX), Guaiacol peroxidase (GPX), Superoxide dismutase (SOD) and Catalase (CAT) were estimated in this experiment.
    Results
    Based on the results, increasing of stress severity reduced some traits, So that the soil’s water content lose to the 75% of the field capacity led to decrease in dry matter, Chlorophyll a, b and T.Chlorophyll of the plant’s leaf. However, total phenolic content, Proline concentration, the Peroxidase (POD), Ascorbate peroxidase (APX), Guaiacol peroxidase (GPX), Superoxide dismutase (SOD) and Catalase (CAT) activities were increased. Also, the results of simple effects of foliar application levels showed that by increasing the concentration of foliar application, the traits were increased, so that The highest Chlorophyll a and relative water content of leaf was obtained in plants treated with 100 mg.l-1 TiO2 and on the other hand, the results of reciprocal effects showed The highest phenolic content, Proline concentration, and the activities of POD, APX, GPX, SOD and CAT were obtained in plants subtended in depletion of soil water content up to 75% of FC and sprayed with 100 and mg.l-1 TiO2.
    Conclusion
    According to the results it could be stated that due to the small size of TiO2 particles and easier penetration into the leaf it can affects growth and photosynthetic properties of sage and by reduced the lipid peroxidation, through increasing the antioxidant defense system activities and the content of osmotic regulators (Proline) of the plant and consequently, leads to cells’ structures stability against water stress.
    Keywords: Antioxidant enzymes, Medicinal plant, Nanoparticles, Photosynthetic pigments
  • Mansoureh Ghavam * Pages 555-566
    Introduction
    Drought is a meteorological event occurring due to the absence of rainfall in a period of time. With the occurrence of drought stress, the water available to the soil is reduced, but the loss of water through evapotranspiration increases continuously. Drought can be effective in reducing the rate of germination and germination percentage, and inadequate The necessity of moisture for germination in soil layers and consequently drought stress in seedling stage is one of the important factors in the lack of desirable seedling establishment in arid regions. Considering the importance and role of medicinal plants in different industries, as well as lack of resources Water and abundance of arid regions in the country, it is necessary by applying techniques on the seeds of these plants, proper management of the production and cultivation of these valuable species, and Increase their performance. The purpose of this study was to investigate and use nanosilver particles in increasing or improving the indices of germination of two important species of Thymus.
    Materials and methods
    Seeds of Thymus genotypes Thymus daenensis Celak and Thymus vulgaris L. from Isfahan Seed Packers Company were obtained. This study was carried out in a factorial experiment in 2009 in a completely randomized design with three replications in University of Kashan. Drying treatments were considered at four levels (0, 0.3, -0.6 and -0.9 MPa) and treatments of silver nanoparticles with four concentrations (0, 10, 20 and 30 mg / l).Data were analyzed by SAS statistical software (ver.9). First, the normalization of all the data from different germination traits, including germination percentage, germination speed, root length and stalk length and seedling strain, were evaluated using Kolmogorov-Smirnov test. . Then analysis of variance of data and comparison of means were done using Duncan's test at 5% level.
    Results and discussion
    The results showed that the interaction of species, drought stress and nanoparticles on germination rate and shoot length were significant at 5% probability level. The highest germination percentage was observed in both species in control treatment and with increasing dryness, germination percentage, germination rate and seed vigor decreased in both species. Thymus daenensis Celak had a higher rate of germination than the species of Thymus vulgaris L. The species of Thymus vulgaris L in comparison with the species of Thymus daenensis Celak has a relatively low level of roots in terms of the length of its cultivation. On the other hand, silver nanoparticles in non-dry conditions in Thymus vulgaris L.caused an increase in the length of the root, but in the species of Thymus daenensis Celak it was not observed. In general, silver nanoparticles in all traits, with the exception of stem length, had only a mild-to-moderate-particle dose of 30 MPa.
    Conclusions
    Under drought stress conditions, silver nanoparticles in all traits, with the exception of stem length, had only a slight increase of -0.3 MPa, which results in the ability of silver nanoparticles to reduce the negative effects of drought stress below -0.3 MPa, especially Proof of nanoparticles with a concentration of 30 mg / l. Due to the favorable germination and rapid seedling growth, better seeding and reduced competition with other plants, the use of nanoparticles in these two important species of thyme can be a good way to produce these two species in drought conditions. In the life span of the plant, rarely favorable conditions are provided in terms of different environmental characteristics, and as a result, the actual germination in the field is less than the predicted value in germination tests. Therefore, seed vigor index can be more effective in determining the seed germination rate in the field. However, increasing the index of seed vigor with the presence of silver nanoparticles at low levels of dryness has been proved in these two species, but to check other characteristics of the above plants, we need additional testing in field conditions.
    Keywords: Lamiaceae, Seed, Vigor, Rate of germination
  • Hamad Dris, Seyed Keyvan Marashi * Pages 561-571
    Introduction
    Wheat is the most important crop in the country. However, a significant portion of this product is grown and produced in saline lands. In Khuzestan province, when we move from north the south, the land salinity is increased due to low slope, heavy soil texture and high water deficit. So, the major areas in Ahvaz, Shadegan, Abadan, Khorramshahr, Mahshahr, Dashte Azadegan, Hoveizeh and even in parts of Shoshtar, Ramhormoz and Behbahan are confronted with this limitation. Estimates showed that at least 400,000 hectares of south of province require underground drainage. Many studies have shown that the application of growth regulators such as salicylic acid can increase plant tolerance during abiotic stresses, especially salinity stress. Therefore, this experiment aimed to investigate and compare the effects of different methods of salicylic acid hormone application on quantitative, qualitative and biochemical parameters of wheat in drained and non-drainage lands.
    Materials and methods
    This experiment was carried out in order to evaluate the effects of different methods of applying salicylic acid on quantitative, qualitative and biochemical parameters of wheat in drained and not drained lands, based on combined analysis with randomized complete block design with three replications. The first factor was two levels of drained lands (first experiment) and not drained lands (second experiment) and the second factor was different methods of salicylic acid application, which was 1- no spraying (control), 2- soaking of seeds 3- spraying at the beginning of tillering, 4- soaking of seeds + spraying at the beginning of tillering, 5- spraying at the end of tillering, 6- soaking of seeds + spraying at the end of tillering. In this experiment, salicylic acid was used at a concentration of 1 mM. Soaking of seeds in solution was done for 6 hours and washed with distilled water and then dried. Also, spray application of salicylic acid in different growth stages, was performed by motor sprayer. Determination of grain yield from one square meter was done from each plot after removal of margins. To determine the number of spikes per square meter, the number of spikes in harvesting area was counted and averaged in each plot. To determine the number of grains per spike, 10 spikes were selected randomly from all harvested spikes and their grains were counted and their mean was considered as grains number per spike. To determine the number of spikelets per spike, 10 spikes were cut in each plot randomly and the number of spikes was counted and their mean was considered as spikelets number per spike. 1000-grain weight was calculated based on the total weight of two 500 grains samples at the harvest stage. Chlorophyll index was determined by using chlorophyll meter at grain filling stage. Different concentrations of proline, in mg/g fresh weight, were measured by Bates method and wheat protein was measured by digestion method by Kejeldal device.
    Results and discussion
    The results showed that the effect of land type on spikes number per square meter, grains number per spike, spikelets number per spike, 1000-grain weight, grain yield, chlorophyll index, proline and grain protein percentage were significant at 1% probability level. The effect of salicylic acid levels on all traits was significant at 1% probability level. The interaction of land type and salicylic acid in terms of protein percentage was significant at 5% probability level and in term of spikes number per square meter, spikelets number per spike, 1000-grain weight, chlorophyll index and proline content were significant at 1% probability level. The maximum protein percentage (14.36%) was related to the no spraying of salicylic acid (control) in non-drainage conditions  and the minimum in drained conditions (10.6%) was related to soaking of seeds + spraying at the beginning of tillering. The maximum and minimum grain yield in drained and non-drained lands by 3308 and 2017 kg.ha-1 was observed, respectively and the maximum and the minimum grain yield in different methods of salicylic acid application was in seed soaking + spraying at the beginning of tillering and without salicylic acid application by 3636 and 1759 kg.ha-1, respectively.
    Conclusions
    In general, the results showed that the effect of salicylic acid on drained lands increased the yield parameters and on not drained lands by reducing the effects of salinity stress and improving the damage caused by it could be effective in increasing of yield. However, in this condition, the lowest yield qualitative was observed.
    Keywords: Salinity stress, Soaking, Spraying, Wheat, Yield
  • Marieh Sadat Mirfazeli *, Gholam Abbas Akbari, Hosseinali Ramshini Pages 567-578
    Introduction
    Basil (Ocimum basilicum L.) is a medicinal plant, annual herb of the Lamiaceae family. It is extremely important because of the large amounts of essential oils in the vegetative organs and the diversity of the secondary compounds in the essential oils. Salinity is one of the important factors limiting the growth of plants and causes osmotic stress and ionic toxicity. Drought stress reduces the rate and percentage of emergence and finally lead to delay seedling establishment. Therefore, tolerance to stress in the early stages of plant development is very important and seedlots that have the ability to germinate under stress conditions, have a successful establishment, have a good density and have a high crop yield. In this regard, the aim of this study was to identify tolerate basil accessions to salinity and drought stresses at the emergence stage.
    Materials and methods
    This experiment was conducted as a factorial based on a completely randomized design in 2017. Twenty basil accessions were planted under control, salinity and drought conditions in the greenhouse and seedling emergence were recorded daily. In this study rate and percentage of seedling emergence, mean emergence time (MET), and emergence energy (GE), genetic and phenotypic variations, coefficient of genetic and phenotypic variations, and broad sense heritability for the evaluated traits were calculated.
    Results and discussion
    The results showed that all of the accessions in the control conditions had a high emergence percentage of salinity and drought conditions. Under stress conditions, some of the accessions had high emergence percentage; the results of analysis of variance showed that the difference among the accessions for emergence percentage and rate, mean emergence time and emergence energy in the control conditions. However, most of these differences were not significant under drought and salinity stress conditions. This indicates the high susceptibility of the Basil, which, in the conditions of salinity and drought, has not been much disagreement among the accessions. In control conditions, the highest percentage of emergence was observed in Isfahan 2 accessions. Regarding the traits of emergence, the least time to emergence, the greatest energy of emergence of Shiraz accession was better than other accessions. In the conditions of control, the percentage of the accessions and the rate of emergence were higher in drought stress than in other accessions. In other words, the difference among accessions in terms of drought stress was lower. In the conditions of salinity stress, a similar trend was observed with drought stress, and the difference between the accessions in these conditions was less than the control conditions. In drought stress, the average time to emergence of Birjand (purple) in 7 days, and in Soiis and Gorgan in 11 days, it can be concluded that in drought stress of Birjand (purple) accession, less time needed for emergence and has better performance in dry soils, although its difference It was not meaningful with some other accession. With the stress, emergence energy decreased. The differences in emergence energy among accessions were significant in the control and drought conditions, but it was not significant in salinity conditions. In control conditions, the highest emergence energy was related to the Shiraz accession and the lowest amount of emergence energy was the Soiis accession. Also, under drought stress, the lowest emergence energy was associated with the Napoleonic accession and most related to the Malayer green accession.
    Conclusions
    The results showed that Isfahan2 and Shiraz under control condition, Isfahan 2, 3 and Birjand under drought stress and Pishva (Green) and Zahedan under salinity conditions, had better seedling emergence and establishment than the other accessions. In this research, genotypic and phenotypic variances, genotypic and phenotypic variation coefficients and broad sense heritability were estimated for the traits. Finally, there was a good variation in tolerance of different accessions to salinity and drought stresses, which can be used to breed new basil cultivars tolerated to salinity and drought. It should be noted that further studies on essential oil content and yield of these accessions should be studied in future studies in order to make a better selection.
    Keywords: Broad sense heritability, Emergence rate, Establishment, Genetic variation
  • Mohammad Javad Babaie Zarch, Sohrab Mahmoodi *, Seyed Vahid Eslami, Gholam Reza Zamani Pages 573-583
    Introduction
    The cultivation of crops in most parts of the world, in addition to competing with different weed species, is affected by a variety of environmental stresses, including salinity stress. The changes in the growth rate and production of crops under the influence of salinity stress and competition with weeds have been extensively studied. However, what is currently less investigated is the competition of several species of weeds with crops and the competition of crops with weeds under salt stress. Therefore, the aim of this experiment was to evaluate the competition between tumble pigweed, common purslaneand and common millet under soil salinity stress.
    Material and methods
    This study was conducted as a factorial experiment based on a randomized complete block design with three replications. Experimental treatments consisted of two rates of soil salinity (3 and 10 dS.m-1), and different ratios of interference of the three species (tumble pigweed, common purslaneand, millet) including 0-0 -100, 0-25-75, 12.5-12.5-75, and 25-0-75, 50-0-50, 25-25-50, 0-50-50, 75-0-25, 37.5-37.5-25, 0-75-25, 0-100-0, 50-50-0 and 0-100-0. The desired density in each pot was constant and equal to 8 plants. After preparing the soil and passing through a 2 mm sieve, fertilizer and saline solutions were added to the soil and the soil was transferred to 5 kg pots. Then all three plants were planted and attained to intended density at the four leaf stage. At the end of the experiment, each plant species was separately harvested from each pot and were weighed after complete drying. Finally, for analyzing the results of the experiment, relative yield indicators, total relative yield (Land Equal Ratio), relative crowding and agressivity indices were used.
    Results and discussion
    The results showed that increasing soil salinity decreased the dry matter produced by common millet, tumble pigweed and common purslane by 19.5, 4.7 and 27.8 percent, respectively. Comapring the relative yield of millet with those of tumble pigweed and common purslane and also both weeds together by different ratios of planting showed that these values were more than predicted ones under either 3 or 10 dS.m-1 salinity level, which indicates the weak competitive ability of these two weeds against millet. The results of the relative crowding index of species showed that in the ratio of 75% of millet and 12.5% tumble pigweed and 12.5% of common purslane, the greatest rate of relative crowding index was achieved for millet under salinity level of 3 dS.m-1. Also, the greatest relative crowding index of tumble pigweed and common purslane under either salinity level was observed with the cultivated ratio of 75% for both weeds and 25% for millet, suggesting an increased competitive ability of these two weed species through increasing their density even under a higher level of soil salinity. By evaluating the agressivity index between tumble pigweed and purselane, it was found that this value was negative for purselane under the salinity level of 3 dS.m-1. Therefore, it seems that tumble pigweed is more competitive than the common purslane where both weed species grow together.
    Conclusion
    In general, the results of this study showed that in conditions of salinity of 3 and 10 dS.m-1, common millet had more competitive ability than the two studied weeds, but with increasing salinity level, competitive ability of millet was reduced, while it increased weeds competitiveness. Therefore, in the situation of high weed densities, we may expect a greater damage to crops under salinity stress.
    Keywords: Agressivity index, Cereals, Competitiveness, Dry matter, Inter-specific competition
  • Vahid Atlassi Pak *, Omid Bahmani Pages 579-588
    To assess the effects of sodium exclusion on leaf chlorophyll content and biomass production, three bread wheat cultivars with contrasting of sodium concentration and different salt tolerance were grown at 2 salinity levels (0 and 150 mM NaCl) under hydroponics and greenhouse conditions in 2017 year. Salinity decreased yield, shoot dry weight, shoot K+/Na+ ratio and chlorophyll content and increased shoot Na+ compared to control. In this experiment, shoot K+ was not affected by salinity. Shoot Na+ concentration was more in salt tolerant cultivar (Kavir) than Mahdavi and Tajan under salinity stress and there was no relationship between Na+ exclusion and salt tolerance in cultivars. Leaf Na+ concentration were much lower in Mahdavi than two other cultivars. Chlorophyll content showed the most decreases in Tajan (75%) than Kavir and Mahdavi under salinity stress. Yield and shoot dry weight was reduced to the same extent (40% and 37% respectively) by 150 mM NaCl in each cultivar, despite greater chlorophyll content by Kavir cultivar. Results showed that Kavir had the highest ability to tolerate high leaf tissue concentrations of Na+. Despite different sodium concentration, the reduction in shoot biomass under salt stress was the same for all cultivars. It seems that the major effect of salinity on shoot biomass and yield was due to the osmotic effect of salt, not due to Na+-specific effect within the plant.
    Keywords: Osmotic effects, Shoot dry weight, Sodium exclusion, Yield
  • Majid Ghanbari *, Ali Makhtassi Bidgoli, Parniyan Talebi Siah Saran, Hassan Pirani Pages 585-594
    Introduction
    Legumes are one of the most important crops to be effective in amending and fertilizing soils. Among legumes, bean, lentil, chickpea, broad bean and pea are most susceptible to salinity (Cobely, 1996). Abiotic stresses affect different aspects of plant growth, such as reduction and delay in germination, decrease in development rate, decrease in plant organs growth, decrease in plant life duration and finally decrease in dry matter production. Among abiotic stresses, salinity stress is considered to be the most influential type of stress in the production of legumes in the world and can greatly reduce production on many arable lands. One of the primary effects of salinity is the reduction of water content of plant tissues. Reducing water availability is due to an increase in the osmotic potential of salt in the root zone (Ghanbari et al., 2016). Seed priming is one of the methods for improving seed quality in which the seeds are exposed to water under controlled conditions, so that different metabolic and physiological activity occur at different levels of moisture inside the seed for germination before the radicle emergence and then seeds are dried to reach initial moisture (Farooq et al., 2006).
    Material & Methods
    To evaluate the effect of salinity and seed aging on germination characteristics of bean seeds, Sadri variety, a factorial experiment was conducted in a completely randomized design with four replications in Agriculture Laboratory, Faculty of Agricultural Sciences, University of Guilan in 2014. The treatments consisted of two groups of seeds (natural and aged) and five salinity treatments (0, 2, 4, 6 and 8 dS m-1). Before testing, seeds were disinfected with 10% sodium hypochlorite solution for 15 minutes (Ghanbari et al., 2016) and washed three times with distilled water. For aging, dried beans were exposed to a temperature of 41 °C and high relative humidity (100%) for 72 hours in an oven placed in a desiccator. Then, 25 seeds were put in each sterile petri dish with filter paper. To each petri dish, five milliliters of NaCl solution with potentials of 2, 4, 6, 8 dS/m were added and distilled water was added as control treatment. After applying the treatments, the petri dishes were covered with parafilm and were placed in the germinator at 25 °C in the dark for 8 days (Ghanbari et al., 2016).
    Results
    The results showed that there were significant differences between treatments for all the variables. In addition, the interaction of seed aging with salinity stress had highly significant difference at the probability level of 5% of plumule fresh weight and there were significant differences at the probability level of 1% for radicle and plumule dry weight, allometric index, seedling tissue water percentage and seed vigor, while regarding of means and percentage of germination and plumule length were not observed significant differences. Research on the effect of seed aging and salinity stress on bean germination characteristics showed that increasing the aging period and increasing levels of salinity stress negatively affected the bean germination characteristics and by the effect on plant water relations, toxicity due to ion accumulation, plasma reduction, molecular structure change of nucleic acids and decreased activity of enzymes eventually led to decreases in germination indices (Ghanbari and Karamnia, 2016).
    Conclusion
    Increasing levels of salinity stress and aging the seeds reduced the activity of germination, mean time and germination percentage, and seedling growth. the results of seed deterioration can be destroyed the buildings the cell membrane with attack free radicals produced due to lipid peroxidation over the period deterioration noted. Therefore, seed aging and increase levels of salinity stress on the germination and its related factors in bean seed had a negative impact and through its impact on plant water relations, toxicity of ion concentration, reducing the plasma membrane integrity, change the molecular structure of nucleic acids and reduction of activity of enzymes eventually reduced the germination indices.
    Keywords: aging, Cultivar Sadri, Enzymatic activity, NaCl, Seedling Morphology
  • Mohammad Hossien Saberi, Elias Arazmjoo *, Ashkboos Amini Pages 589-599
    Introduction
    Salinity stress is a serious threat of plant growth and production over the world. Soil salinity is the major problem, which affects the yield of wheat crop. It is commonly observed in arid and semi-arid regions of the world (Atlassi et al., 2009). Crop growth reduction due to salinity is generally related to the osmotic potential of the root-zone soil solution. The relative salt tolerance of wheat crop is 7.0 dS∙m−1 and its yield decrease is 25% at 9.0 dS∙m−1 (Kramer and Amtmann, 2012). The reduction in growth and yield varies between cultivars (Sultana et al., 2000). The varietal differences in salinity tolerance that exist among crop plants can be utilized through screening programs by exploiting appropriate traits for salt tolerance. The recently developed cultivars form a much diversed genetic base and may therefore possess a wider range of salts stress tolerance.
    Materials and Methods
    In order to study the effects of salinity stress on grain yield, yield components, morphological traits and concentrations of Na+ and K+ of eight wheat cultivars and elite lines, two separate experiments in randomized complete block design with three replications were conducted at two places of Amirabad (saline condition) and Mohammadieh (none saline condition) in 2009-2010. Four elite lines including MS-88-8, MS-88-16, MS-88-17 and MS-87-8 and four salt tolerant cultivars including Ofogh, Arg, Bam and Kavir investigated. The first experiment conducted at the Research Farm of Birjand University located in Amirabad region which texturally the soil was sandy clay loam, with pH=8.2 and EC=13.69 ds.m-1. The second experiment conducted at the South Khorasan Agricultural and Natural Resources Research and Education Center located in Mohammadieh region which texturally the soil was loam, with pH=8 and EC=4.79 ds.m-1. Investigated traits were including flag leaf area, spike length, peduncle length, plant height, number of grain per spike, thousand grain weight, biological yield, grain yield, harvest index, Na+ and K+ concentrations and stress indices. Data analyses were performed using two-way analysis of variance with SAS 9.1. Means of treatments were compared according to Duncan test at the 5% level.
    Results and Discussion
    Results showed that salt stress led to significant reduction on all morphological traits and had the most effect on plant height. Salt stress had no effect on number of grain per spike, 1000 grain weight, and Na+ and K+ concentration in shoot. Biomass and grain yield in salt stress condition decreased 38.2 and 44.5 percent, respectively. MS-87-8 and Ofogh with grain yield of 4.02 and 3.72 ton/ha were better than Bam and Kavir checks and same as Arg. The best indices for selection of tolerant cultivars were HARM, STI and GMP, which Arg and MS-87-8 identified as the most tolerant based on them.
    Conclusion
    The results of this experiment showed that salinity significantly reduced grain yield, biomass and morphological traits of wheat cultivars and promising lines. Meanwhile, Arg cultivar and then MS-87-8 line had the highest grain yield and identified suitable for saline condition. Due to the presence of salinity resistance genes, they can be used for breeding of cultivars with high potential yield and also to cultivate in saline conditions.
    Keywords: 3D scattering, Flag leaf area, Harvest index, Nutrient concentration
  • Leila Mehdizadeh, Mohammad Moghaddam *, Amir Lakzian Pages 595-606
    Introduction
    Salt stress is one of the important reasons of different problems in agricultural productions. Also, because of competition between sodium (Na+) with essential cations that necessary for cellular function, salinity cause to limit in absorption of mineral contents and growth reduction. One way of exciting salt from soil profile is using organic amendments such as biochar that recently has been extremely considered as a result of the weather modifications and soil management. Due to the characteristics of organic matter biochar, in this research the effect of biochar on growth traits, sodium (Na+) and potassium (K+) concentration of summer savory leaf under salt stress resulting from irrigation with NaCl were investigated.
    Materials and methods
    In order to investigate the effect of biochar on growth characteristics, sodium (Na+) and potassium (K+) concentration of summer savory ( Satureja hortensis L.) leaf under NaCl stress, a pot experiment was performed as factorial based on completely randomized design with four replications in greenhouse condition at Horticultural Research Station, Ferdowsi University of Mashhad, Iran, in 2017. The factors of the test included three levels of biochar (0, 1 and 2 % w/w of soil of each pot) and irrigation with salty water in three levels of salinity (0, 40, 80 mM NaCl). In order to produce biochar, the woods of mulberry (Morus alba) three put in electrical furnace with 530 C temperature for 14 h. Then the biochar crushed in very small pieces, sieved and added to the soil. The growth parameters included height, number of branch let, stem diameter, number of nodule, stem fresh and dry weight, leaf fresh and dry weight were measured by common methods. The amount of Na+ and K+ from the leaf samples were also measured. Data analysis were done with Minitab 17 software.
    Results and discussion
    The results of analysis of variances showed that the interaction effects of salinity and biochar treatments on number of branch let, stem diameter, number of nodule, stem fresh and dry weight, leaf fresh weight, Na+ , K+ and K/Na ratio in P<1% and on height and leaf dry weight in P< 5% were significant. The mean comparison of data indicated that the highest plant height (32.17 cm), number of branches (18.92), number of nodule (10.25), stem diameter (11.88 mm), stem fresh (1.75 g/plant) and dry (0.6 g/plant) weight, leaf fresh (3.44 g/plant) and dry (0.82 g/plant) weight were observed at the treatment of 2% w/w biochar without salinity were observed. Furthermore, the highest Na+ (1.69% leaf dry weight ) and K+ (3.39% leaf dry weight) were observed at 80 mM NaCl without using biochar and the treatment without salinity and biochar (control( , respectively. With increasing salt concentration, the K/Na ratio decreased and at the highest salt concentration (80 mM) reached to the lowest amount (1.71%). Salinity stress through limitation in mineral element, disrupting ionic balance, deficit in available water of plant and toxicity of mineral element cause to reduce cell growth. Competition between Na+ and K+ is one of the important physiological mechanisms of salinity stress resistance. K+ deficit is one of the events that occur due to the competition between Na+ with K+ for absorption in the roots. Therefore, it seems that in this experiment application of biochar resulted in increasing the tolerance to salinity by decreasing absorption of Na+ with plant and increasing K/Na ration.
    Conclusions
    The results of this study showed that salinity cause to reduce the growth of summer savory and application of biochar in this condition cause to balance the harmful effects of salinity. In the treatment 80 mM NaCl without using biochar, the highest reduction in studied traits was observed. Moreover, adding biochar by absorbing Na+ of soil cause to reduce Na+ of plant. Due to the results of this research, correct application of biochar could be a suitable biological way for increasing the tolerance of plants to salinity
    Keywords: Agricultural char, Pyrolysis, Saline water, Salinity stress, Saline soil management
  • Hana Aboodeh, Mohammad Reza Moradi Telavat *, Ali Moshatati, Seyyed Hashem Mousavi Pages 607-616
    Introduction
    To plant breeding in relation to high temperature tolerance, and for determining the differences between resistant genotypes, several indices in the basis of crop yield in normal and stressed conditions were be introduced. With regard to importance of genetic breeding for higher yield and stability in exposure to terminal heat stress in warm region of Iran, and little studies about tolerance of safflower cultivars, this study was carried out by measuring tolerance and sensitivity indices. Safflower is one the most important oil crops in regions that have dry and warm winters like to Khuzestan province of Iran. This crop are relatively tolerant to environmental stresses. But it is reported there are significant differences between different cultivars. The study was conducted to evaluate the difference between safflower cultivars in Ahvaz region.
    Materials and Methods
    To comparison of safflower cultivars by indices of tolerance and sensitivity to terminal heat stress, present study was carried out in Ramin Agriculture and Natural Resources University of Khuzestan, at 2016-2017. A split plot design in the basis of Randomized Complete Blocks Design (RCBD) with four replications was used for the study. Experimental factors was included four sowing date (11 November, 2 December, 5 January and 3 February) were placed in main plots, and safflower cultivars (sina, goldasht, soffeh, Esfahan local (kooseh) and faraman) were placed in subplots. In this study, several indices with regard to researcher’s reports were calculated and used for determining the difference between safflower cultivars. Statistical analysis was done using by SAS v. 9.1 software.
    Results and Discussion
    The results of statistical analysis showed that investigated cultivars had significant differences in terms of Stress Sensitivity index (SSI), Tolerance Index (TI), Productivity Mean (PM), Harmonic Mean (HM), Yield Stability Index (YSI), (GPM), Stress Tolerance Index (STI), Stress Damage Index (SDI), and Modified Stress Tolerance for appropriate conditions (MSTI1), Modified Stress Tolerance for no appropriate conditions (MSTI2), and Yield Reduction Index (YRI). However, differences between cultivars in terms of Ranking Index (RI) and Yield Index (YI) were not significant. Therefore, STI was the best index for evaluating tolerance and sensitivity of safflower cultivars to terminal heat. On the basis of STI, most tolerate and sensitive cultivars were goldasht and Esfahan local (kooseh), respectively.
    Conclusion
    The results showed that safflower cultivars had significant differences in terms of tolerance indices calculated in the study. In the basis of Stress Tolerance Index (STI), goldasht cultivar had highest tolerance (lowest sensitivity) and local Esfahan cultivar (kooseh) had lowest tolerance (highest sensitivity) to terminal heat stress.
    Generally, in regions exposed to environmental stress, best cultivars are the cultivars that in normal conditions have high yield and in stressed conditions have no significant reduction f yield (group-A in Fernandez classification). In this study, stress tolerance index (STI) had good ability for determining of these cultivars.
    Keywords: Cultivar, Grain yield, Oil seed, Sowing date
  • Fatemeh Taleh Farahi, Ahmad Gholamalizadeh *, Arash Hemati Pages 617-630
    Introduction
    Calcareous soils, show serious limitation in accessing of nutritional elements. Majority of Iran’s soils are placed in arid or semi-arid regions and they are also in Alkali and lime conditions. As this calcareous soil mostly placed in hot climate conditions, naturally they are poor in organic matter. Humic materials are main and persistence components in organic matter and they could increase the growth of plants as well as the nutritional elements sorption. Humic acid is a natural organic Polymer Which as a result of the decomposition of soil organic matter, pit and lignin will be created and they will improve yield and quality of plant products. Humid matters will increase the resistance of plants in inappropriate environmental conditions. In spite of extended research on extraction and use of humic acids in plant nutrition, there is a limit attention in comparison effects of humic acid extracted from different sources on plant yield in calcareous soils. Hence the aim of this research is the effects of extracted humid acids from different sources on sunflower yield in soils with permanent lime stress.
    Materials and methods
    This research performed in greenhouse of university on sunflowers. The method was completely randomized factorial design with 3 replications in 2014-2015. Treatments were included: Soil application and foliar application with 5 sources of humic acids (Biochar 400 degree, biochar 200 degree, Sludge, manure and control). Humic acid treatments both in Soil application and foliar application were performed in 4 stages. Moreover of plant traits, (including Number of leaves per plants, stem length, fresh and dry weight, ash weight, Chlorophylls a, b, total and carotenoids and concentrations of phosphorus and potassium elements), there are also physical and chemical properties of extracted humic acids (including humic acid percentage, carboxylic groups, total acidity, OH-phenolic groups, and E4/E6, E3/E5 ratios) that they were measured.
    Results and Discussion
    Studying results of the physical and chemical properties of extracted humic acids, shows that the highest amount of extracted humic acid was observed in sludge treatment which had the highest proportion among other resources. Also according to the results, the highest amount of phenol groups, carboxylic groups and total acidity were observed in humic acid extracted from manure. The highest ratio of E3/E5 (the largest molecular size of humic acid) is related to humic acid extracted from biochar 400 degree. The smallest molecular size (E3/E5) was observed in the treatments of humic acid extracted from biochar 200 degree. The results showed that the humic acid extracted from any sources, had a positive effect on all traits of the plant and increased all traits significantly. In Foliar application treatments, The highest increase in leaf number, chlorophyll a, b, total and carotenoids and potassium was observed; where Soil application of humic acid sources showed the highest increase in stem length, dry weight, ash weight and phosphorus of plants. Humic acid extracted from sludge had a significant effect on stem length (63%), chlorophyll a (47%) and phosphorus (1.25 times). Also in compare with control, the humic acid extracted from biochar 200 degree, had a positive effect on the number of leaves (59%), fresh weight (60.23%) and dry weight (1.21 times), chlorophyll b (1.13 times), total (35%) and carotenoid (62%) and potassium (36%). Interaction effects of biochar 200 degree, had a positive effect on traits like the number of leaves (61%), dry weight (1.4 times), chlorophyll a (62%), total (64%), potassium (45%); also biochar 400 degree, had a positive effect on traits like chlorophyll b (1.5 times) and carotenoid (50%); soil application used biochar 200 degree had a positive effect on traits like fresh weight (75%); sludge had a positive effect on stem length (58%) and phosphorus (1.75 times) and manure had a positive effect on traits like ash weight (3.22 times), and this things all together had a positive effect on plant growth and yield.
    Conclusion
    In general, according to the results, the foliar application of Humic acid extracted from biochar 200 degree had the best performance on increasing the yield and its components, which may be attributed to the small molecular size of the extracted humic acid from biochar 200 degree.
    Keywords: Chlorophyll, Foliar application, Humic Materials, Oilseeds, Sludge