فهرست مطالب

  • سال دوازدهم شماره 1 (بهار 1398)
  • تاریخ انتشار: 1397/12/21
  • تعداد عناوین: 24
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  • علی ماهرخ *، مجید نبی پور، حبیب الله روشن فکر، رجب چوکان صفحات 1-15
    این مطالعه به منظور تعیین پاسخ برخی صفات فیزیولوژیکی ذرت دانه ای در هیبرید سینگل کراس 704 به تغییرات هورمون های سیتوکینین و اکسین در شرایط تنش خشکی اجرا شد. آزمایش در سه محیط جداگانه، شامل محیط بدون تنش خشکی، تنش خشکی در مرحله رشد رویشی و تنش خشکی در مرحله رشد زایشی انجام شد. هورمون های سیتوکینین در سه سطح (شاهد، محلول پاشی در مرحله پنج تا شش برگی و هشت تا ده برگی) و اکسین در سه سطح (شاهد، محلول پاشی در مرحله ظهور ابریشم و 15 روز پس از ظهور ابریشم) در هر محیط درسه تکرار بصورت فاکتوریل در قالب طرح بلوک های کامل تصادفی در مزرعه موسسه تحقیقات اصلاح و تهیه نهال و بذر کرج در سال زراعی 1392 اجرا شد. بیشترین شاخص سطح برگ، هدایت روزنه ای و کارایی کوانتوم فتوسنتزی و کمترین دمای کانوپی با محلول پاشی هورمون سیتوکینین در مرحله هشت تا ده برگی بدست آمد، و بیشرین میزان کلروفیل برگ، کارایی کوانتوم فتوسنتزی و روند تاخیری در پیر شدن برگ با مصرف هورمون اکسین در مرحله ظهور ابریشم و کمترین مقاومت روزنه ای و دمای کانوپی با مصرف هورمون اکسین در زمان 15 روز پس از ظهور ابریشم حاصل شد. اثر متقابل تنش خشکی و مصرف هورمون ها بر شاخص سطح برگ و کاهش دمای کانوپی معنی دار بود و تاثیر گذاری مصرف هورمون ها در گیاه ذرت در شرایط تنش زایشی به دلیل برقراری تعادل روابط هورمونی مختل شده نسبت به محیط عدم تنش و تنش رویشی موثرتر بود.
    کلیدواژگان: دمای کانوپی، هدایت روزنه ای، هیبرید 704، کارایی کوانتوم فتوسنتزی، دمای برگ
  • سید محمد جواد بحرالعلومی *، محمود رایینی سرجاز، همتاللهپیردشتی صفحات 17-28
    این پژوهش با هدف بررسی تاثیر تنش خشکی بر فعالیت آنتی‌اکسیدان‌های آنزیمی گیاه سویا (رقم ساری)، در سال 1391 در دانشگاه علوم کشاورزی و منابع طبیعی ساری انجام شد. در این پژوهش اثر چهار تیمار آبی در یک آزمایش گلدانی در قالب طرح کاملا تصادفی با شش تکرار بررسی شد. گیاهان پس از مرحله‌ی چهار برگی به تصادف به چهار سطح آبی 100 (شاهد، W0)، 60 (تنش ملایم، W1)، 40 (تنش میانه، W2) و 20 (تنش شدید، W3) درصد آب قابل دسترس (AW) اختصاص یافتند. در ابتدا همه تیمارها تا 100 درصد آب دسترس آبیاری شدند و آبیاری‌های بعدی پس از رسیدن رطوبت خاک به درصد تعریف‌شده برای هر تیمار انجام می‌شد. در مرحله‌های زایشی R4 و R5 (45 روز پس آغاز تنش) اقدام به نمونه‌برداری برای سنجش آنزیم‌ها و نیتروژن برگ شد. یافته‌ها نشان داد که فعالیت آنزیم کاتالاز تا 60 درصد آب قابل دسترس، نسبت به شاهد 65 درصد افزایش داشت، آنگاه با افزایش شدت تنش فعالیت آن کاهش یافت. همچنین فعالیت آنزیم پراکسیداز، مقدار مالون‌دی‌آلدئید (MDA) و نیتروژن کل برگ نیز با کاهش آب خاک، تا سطح 20 درصد آب قابل دسترس نسبت به شاهد به ترتیب 43، 22 و 26 درصد افزایش یافت. با کاهش 20 درصدی آب قابل دسترس، مقدار پروتئین محلول برگ نسبت به شاهد 12 درصد کاهش نشان داد و تفاوت معنی‌داری میان تیمارهای W2 و W3 و شاهد دیده شد. نتایج گویای آن است که در تنش خشکی ملایم فعالیت آنزیم‌های آنتی‌اکسیدانی افزایش یافت و پیامد آن، کاهش آسیب گونه‌های فعال اکسیژن (ROS) بود که خود باعث نقش حفاظتی بسیار موثری در مراحل فتوسنتزی گیاه می‌گردد. نتیجه این سازوکار فیزیولوژیک بهبود عملکرد دانه در بوته در بازه تخلیه رطوبتی فوق بود.
    کلیدواژگان: آب قابل دسترس، پراکسیداز، کاتالاز، گونه های فعال اکسیژن
  • حمداله اسکندری *، اشرف عالی زاده امرایی، کامیار کاظمی صفحات 29-40
    به منظور بررسی اثر الگوی کاشت و روش آبیاری بر عملکرد دانه و کارآیی مصرف آب ذرت و ماش، آزمایشی به صورت فاکتوریل دو عاملی در قالب طرح بلوک های کامل تصادفی با سه تکرار در سال زراعی 96-1395 در استان لرستان اجرا شد. عامل اصلی شامل دو روش آبیاری (آبیاری کامل (I1) و آبیاری جزئی (I2) ریشه ) و عامل فرعی الگوی کشت (کشت خالص ذرت و ماش، و کشت مخلوط ذرت و ماش روی ردیف های جداگانه و روی یک ردیف) بود. تجزیه واریانس داده ها با نرم افزار MSTATC انجام گرفت. نتایج بدست آمده نشان داد که عملکرد دانه ذرت و ماش با اعمال آبیاری جزئی ریشه کاهش یافت. به طوری که عملکرد دانه ذرت در شرایط آبیاری جزئی ریشه در کشت خالص 45%، در کشت مخلوط روی ردیف های جداگانه %29 و در کشت مخلوط روی یک ردیف 26% نسبت به آبیاری کامل کمتر بود. عملکرد دانه ماش نیز با اعمال آبیاری جزئی ریشه در تیمارهای کشت خالص، کشت مخلوط روی ردیف های جداگانه و کشت مخلوط روی یک ردیف به ترتیب 29، 22 و 21 درصد نسبت به آبیاری کامل کاهش یافت. بیشترین کارآیی مصرف آب (2.77 کیلوگرم در متر مکعب) در کشت مخلوط ذرت و ماش روی یک ردیف در شرایط آبیاری جزئی ریشه بدست آمد. در شرایط آبیاری معمولی بیشترین کارآیی مصرف آب به کشت مخلوط ذرت و ماش روی یک ردیف اختصاص داشت که از کشت خالص ذرت، کشت مخلوط روی ردیف های جداگانه و کشت خالص ماش به ترتیب 23، 50 و 76 درصد بیشتر بود. بنابراین، کشت مخلوط ذرت و ماش روی یک ردیف در شرایط آبیاری جزئی ریشه می تواند ضمن تولید مطلوب دانه، باعث افزایش کارآیی مصرف آب شود. نسبت برابری زمین در کشت مخلوط ذرت و ماش روی یک ردیف و در شرایط آبیاری جزئی ریشه (2.25) مزیت این الگوی کشت را تایید می کند.
    کلیدواژگان: آبیاری محدود، کارآیی مصرف آب، نسبت برابری زمین
  • محسن رضایی، حسین صبوری *، عبدالطیف قلی زاده، رحمت الله محمدی گنبد صفحات 41-54
    تنش خشکی ناشی از کم آبی و گرمای آخر دوره رشد، از مشکل های مهم در کشاورزی به شمار رفته و یکی از مهم ترین عوامل کاهش عملکرد گیاهان زراعی می باشد. از همین رو به منظور بررسی آلل های مرتبط با تحمل به خشکی در گیاه جو و همچنین گروه های هاپلوتایپ اثر گذار بر آن این پژوهش به انجام رسید. برای این منظور، آزمایش جهت تعیین فنوتیپ در ایستگاه تحقیقات گنبد کاووس و در قالب طرح اگمنت با 96 ژنوتیپ و 4 شاهد اجرا شد و 18 صفت بر روی بوته ها مورد ارزیابی قرار گرفت. سپس برای بررسی تنوع آللی و هاپلوتایپی، ژنوتیپ های مورد آزمایش به وسیله 5 نشانگر ریز-ماهواره مرتبط با تحمل به خشکی آزمون گردیدند. بررسی تنوع آللی میانگین تعداد آلل، محتوی اطلاعات چند شکل و تنوع ژنی را به ترتیب 5.2، 0.6267 و 0.6807 نشان داد که در هر سه بخش آلل GBMS180 دارای بیشترین و آلل Bmag0782 دارای کمترین مقدار بود. همچنین نتایج بررسی هاپلوتایپی 58 گروه هاپلوتایپ را نشان داد. گروه نوزده که شامل ژنوتیپ صد و سی و پنج بود با عملکرد 5183.333 کیلوگرم در هکتار بیشترین عملکرد و مقاومت در برابر خشکی را داشت. تجزیه ارتباط بین داده های مولکولی و فنوتیپی بیان گر این موضوع بود که از میان 16 آلل موثر بر صفت های مورد ارزیابی آلل GMBS183-D با اثر گذاری بر روی سه صفت تعداد دانه در سنبله، تعداد سنبله (در هکتار) و عملکرد (در هکتار) دارای بیشترین اثر گذاری بر روی عملکرد و اجزای آن بود. آلل GMBS183-C نیز با R2 برابر با 23.3 برای صفت تعداد سنبله (در هکتار) بالاترین مقدار ضریب تبیین را در بین آلل های دخیل در صفت های مربوط به عملکرد و اجزا عملکرد دارا بود. در صورت تایید نتایج می توان از نشانگر ها و ژنوتیپ های حاضر در تحقیقات و برنامه های به نژادی استفاده نمود.
    کلیدواژگان: تجزیه ارتباط، جو، خشکی، هاپلوتایپ، QTL، PIC
  • مهدی کاکایی* صفحات 55-74
    از بین تنش های محیطی، تنش خشکی مهم ترین عامل کاهش تولیدات گیاهان در سراسر جهان است. جهت مطالعه تنوع ژنتیکی و ارتباط بین صفات مختلف با عملکرد دانه در 17 ژنوتیپ (شامل ارقام و لاین های مختلف) گندم نان، آزمایشی در قالب طرح بلوک های کامل تصادفی با سه تکرار تحت دو شرایط عدم تنش خشکی و شرایط دیم در سال زراعی 90-1389 در مزرعه آموزشی-پژوهشی دانشگاه پیام نور اسدآباد اجرا گردید. در این آزمایش صفات عملکرد دانه، تعداد دانه در سنبله، طول سنبله، طول برگ پرچم، عرض برگ پرچم، وزن صد دانه، ارتفاع بوته، محتوی نسبی آب برگ، میزان نسبی آب ازدست رفته، درصد سبزینگی برگ (میزان کلروفیل) و مساحت برگ پرچم اندازه گیری شدند. نتایج تجزیه واریانس ساده تنوع بالا و معنی داری را در هر دو شرایط رطوبتی (مکان) نشان داد. نتایج تجزیه واریانس مرکب اثر ژنوتیپ را برای اکثر صفات معنی دار نشان داد. نتایج تجزیه همبستگی نیز بیانگر این بود که بین عملکرد دانه و درصد سبزینگی برگ (اسپاد) در شرایط دیم و بین عملکرد دانه و میزان آب ازدست رفته برگ در شرایط عدم تنش خشکی همبستگی مثبت و معنی داری (P<0.05) مشاهده گردید. نتایج تجزیه خوشه ایژنوتیپ های موردمطالعه را در هر دو شرایط محیطی در سه گروه مجزا و متفاوت قرار داد. به طوری که بیشترین فاصله ژنتیکی در هر دو شرایط رطوبتی بین خوشه اول و سوم مشاهده گردید. تجزیه به مولفه های اصلی در شرایط عدم تنش خشکی و شرایط دیم به ترتیب 71% و 76% از تنوع موجود را توجیه نمودند. با توجه به مقایسه میانگین عملکرد دانه، ژنوتیپ های 7 (3790 کیلوگرم در هکتار)، 8 (3525 کیلوگرم در هکتار) و 13 (3305 کیلوگرم در هکتار) در شرایط عدم تنش خشکی و ژنوتیپ های 13 (2147 کیلوگرم در هکتار)، 14 (2440 کیلوگرم در هکتار) و 17 (2254 کیلوگرم در هکتار) در شرایط دیم بیش ترین عملکرد دانه را تولید کردند.
    کلیدواژگان: بای پلات، تجزیه خوشه ای، خشکی، عملکرد، همبستگی
  • نازلی دروگر، مانی مجدم*، بهامین سید حیات غیب صفحات 75-84
    به منظور بررسی تاثیر سولفات روی بر مولفه های کمی و کیفی جو در شرایط تنش خشکی آخر فصل، آزمایشی در سال زراعی 96-1395 در شهرستان باغملک واقع در استان خوزستان به صورت کرت های یک بار خرد شده در قالب طرح بلوک های کامل تصادفی در چهار تکرار اجراء شد. تیمارهای آزمایش شامل رژیم های آبیاری در سه سطح (قطع آبیاری در مرحله گلدهی، دانه بندی و آبیاری کامل) در کرت های اصلی و کود سولفات روی 34 درصد در سه سطح ( صفر، 30 و 60 کیلوگرم در هکتار) در کرت های فرعی بودند. نتایج نشان که تنش خشکی آخر فصل تاثیر معنی-داری بر صفات عملکرد دانه، تعداد دانه در سنبله، وزن هزار دانه، پروتئین دانه و عملکرد پروتئین داشتند. همچنین کاربرد کود سولفات روی به طور معنی داری اجزای عملکرد، عملکرد دانه و عملکرد پروتئین را تحت تاثیر قرار داد. بیشترین عملکرد دانه با میانگین 3890.6 کیلوگرم در هکتار از تیمار 60 کیلوگرم در هکتار کود سولفات روی و کمترین با میانگین 2360.3 کیلوگرم در هکتار از تیمار شاهد به دست آمد. برهمکنش تنش خشکی آخر فصل و کود سولفات روی تاثیر معنی داری بر عملکرد دانه داشت. بیشترین عملکرد دانه به تیمار آبیاری کامل و تیمار 60 کیلوگرم در هکتار کود سولفات روی اختصاص یافت. در نهایت می توان چنین گفت که افزایش کود سولفات روی در شرایط تنش خشکی آخر فصل می تواند اثرات حاصل از تنش را تعدیل نماید و بهترین شرایط را جهت تولید حداکثر عملکرد کمی و کیفی در گیاه جو فراهم سازد.
    کلیدواژگان: اجزای عملکرد، تنش خشکی آخر فصل، سولفات روی، عملکرد کمی و کیفی
  • سارا دیلمی، مانی مجدم * صفحات 85-94
    به منظور ارزیابی اثر زمان محلول پاشی با اسید هیومیک و رژیم های آبیاری بر صفات کمی و کیفی لوبیا چشم بلبلی، آزمایشی در سال زراعی 1395 در شهرستان حمیدیه به صورت کرت های یک بار خرد شده در قالب طرح بلوک های کامل تصادفی در سه تکرار اجراء گردید. تیمارهای آزمایش شامل رژیم های آبیاری در سه سطح (60، 90 و 120) میلی متر تبخیر از تشت تبخیر کلاس A در کرت های اصلی و زمان های مختلف محلول پاشی اسیدهیومیک در سه سطح (عدم محلول پاشی، محلول پاشی در مرحله رویشی و محلول پاشی در مرحله گلدهی) در کرت های فرعی بودند. نتایج نشان که رژیم های آبیاری تاثیر معنی داری بر صفات عملکرد دانه، تعداد غلاف در بوته، تعداد دانه در غلاف و عملکرد پروتئین داشتند. همچنین کاربرد زمان های محلول پاشی اسید هیومیک به طور معنی داری عملکرد دانه و عملکرد پروتئین را تحت تاثیر قرار داد. بیشترین عملکرد دانه با میانگین 200.7 گرم در مترمربع از تیمار محلول پاشی در زمان رویشی و کمترین با میانگین 155.5 گرم در مترمربع از تیمار عدم محلول پاشی بدست آمد. برهمکنش رژیم های آبیاری و زمان های محلول پاشی اسید هیومیک تاثیر معنی داری بر عملکرد دانه داشت. بیشترین عملکرد دانه به تیمار 60 میلی متر تبخیر از تشت تبخیر و تیمار محلول پاشی اسید هیومیک در مرحله رویشی به میزان 213.1 گرم در مترمربع اختصاص یافت. در نهایت می توان چنین گفت که استفاده از اسید هیومیک علاوه بر افزایش در عملکرد کمی و کیفی لوبیا چشم بلبلی می تواند نقش به سزایی را در جهت نیل به اهداف کشاورزی پایدار ایفا کند.
    کلیدواژگان: عملکرد پروتئین، عملکرد دانه، تعداد دانه در غلاف
  • قادر رستمی، محمد مقدم *، الهام سعیدی پویا، لادن آژدانیان صفحات 95-110
    به منظور بررسی اثرات تعدیل کنندگی اسید هیومیک بر تنش خشکی در گیاه نعناع سبز، آزمایشی گلدانی به صورت فاکتوریل در قالب طرح کاملا تصادفی با سه تکرار اجرا شد. تیمارهای آزمایش شامل تنش خشکی در سه سطح (30، 70 و 100 درصد ظرفیت زراعی) به عنوان فاکتور اول و محلول پاشی اسید هیومیک در چهار سطح (صفر، 100، 500 و 1000 میلی گرم در لیتر) به عنوان فاکتور دوم بودند. نعناع سبز قادر نبود بیش از 2 هفته تنش 30 درصد ظرفیت زراعی را تحمل کند و به طور کامل گیاهان این سطح نابود شدند. صفات رویشی گیاه از قبیل ارتفاع بوته، تعداد شاخه فرعی، طول برگ، عرض برگ و وزن تر و خشک برگ و ساقه در تنش ملایم خشکی (70 درصد ظرفیت زراعی) کاهش معنی داری نسبت به تیمار شاهد نشان دادند. محلول پاشی اسید هیومیک به ویژه غلظت 1000 میلی گرم در لیتر تحت تنش خشکی سبب بهبود این صفات نسبت به گیاهان شاهد گردید. بیشترین مقادیر رنگیزه های فتوسنتزی در تنش خشکی 70 درصد ظرفیت زراعی و محلول پاشی 1000 میلی گرم در لیتر اسید هیومیک و کمترین آنها در تیمار عدم تنش خشکی و کاربرد 500 میلی گرم در لیتر اسید هیومیک مشاهده شد. بالاترین میزان فنل کل (0.62 میلی گرم/گرم وزن تر) و فعالیت آنتی اکسیدانی عصاره برگ (60.16 درصد) در گیاهان حاصل از محلول پاشی 1000 میلی گرم در لیتر اسید هیومیک تحت تنش ملایم خشکی مشاهده شد. بیشترین محتوی رطوبت نسبی در شرایط عدم تنش و محلول پاشی 1000 میلی-گرم در لیتر اسید هیومیک حاصل شد. بنابراین می توان'گفت که نعناع سبز گیاهی بسیار حساس به تنش خشکی است و با توجه به کاهش شاخص های رشد و فرایندهای فیزیولوژیکی ناشی از تنش خشکی کاربرد اسید هیومیک به ویژه در غلظت بالا بصورت محلول پاشی می تواند به عنوان کود آلی همراستا با کشاورزی پایدار در تنظیم پتانسیل اسمزی نعناع سبز تحت شرایط تنش خشکی ملایم تا حدودی موثر باشد.
    کلیدواژگان: پرولین، رطوبت نسبی برگ، کلروفیل، مواد آلی
  • حمداله اسکندری *، کامیار کاظمی صفحات 111-122
    این پژوهش به منظور بررسی اثر نوع کود در سطوح مختلف آبیاری بر عملکرد دانه و تولید روغن کنجد (Sesamum indicum L.) (توده بومی شادگان، با طول دوره رشد متوسط و متحمل به آفات و گرما) درسال زراعی 96-1395 در شهرستان شادگان بررسی شد. آزمایش به صورت اسپلیت پلات در قالب طرح پایه بلوک های کامل تصادفی در سه تکرار اجرا شد. سطوح آبی در سه سطح شامل آبیاری پس از 100، 200 و 300 میلی متر تبخیر از تشتک تبخیر کلاس A در کرت های اصلی و نوع کود به عنوان عامل فرعی در چهار سطح شامل شاهد، کود شیمیایی شامل کود فسفره به میزان 250 و کود نیتروژنه از نوع اوره به میزان 100 کیلوگرم در هکتار، کود گاوی به میزان 30 تن در هکتار (با میزان رطوبت 14 درصد) و کود کمپوست (50 درصد زباله شهری و 50 درصد تفاله نیشکر) به میزان 30 تن در هکتار (با میزان رطوبت 21 درصد) در کرت های فرعی قرار گرفتند. تیمارهای کود شیمیایی و کمپوست به صورت جداگانه اعمال شدند. صفات مورفولوژیک (ارتفاع بوته، تعداد برگ در بوته، تعداد شاخه فرعی در بوته)، عملکرد و اجزای عملکرد دانه، درصد و عملکرد روغن برای ارزیابی تیمارها اندازه گیری شد. نتایج نشان داد که عملکرد دانه کنجد در سطح آبیاری 300 میلی متر تبخیر به طور معنی داری (P≤0.01) کمتر از سطح آبیاری 100 و 200 میلی متر تبخیر (به ترتیب 63.5 و 40 درصد) بود. عملکرد دانه کنجد با کاربرد کود شیمیایی، دامی و کمپوست به طور معنی داری (P≤0.01) و به ترتیب 5/47، 34 و 16 درصد نسبت به شاهد افزایش یافت. بیشترین (8/52 درصد) درصد روغن با استفاده از کود شیمیایی و سطح اول آبیاری (100 میلی متر تبخیر از تشتک تبخیر) به دست آمد. بیشترین عملکرد روغن کنجد (644.5 کیلوگرم در هکتار) در سطح اول آبیاری به دست آمد که به طور معنی داری (P≤0.01) بیشتر از سطوح دوم و سوم آبیاری (به ترتیب 17 و 43 درصد) بود. بیشترین درصد افزایش عملکرد روغن با استفاده از کود شیمیایی ثبت گردید که 52 درصد بیشتر از شاهد بود. به طورکلی، برای تولید دانه باشد، سطح آبیاری را می توان به 200 میلی متر تبخیر افزایش داد. با توجه به عدم تفاوت معنی دار عملکرد دانه، مصرف کود دامی برای تولید عملکرد دانه مطلوب با کود شیمیایی برابری می کند و قابل توصیه است.
    کلیدواژگان: تنش خشکی، شاخص برداشت، عملکرد، کمپوست، کود دامی
  • صادق بهامین، علیرضا کوچکی *، مهدی نصیری محلاتی، سید علیرضا بهشتی صفحات 123-139
    کاهش عناصر غذایی در خاک های زراعی دنیا به علت زراعت های متوالی و بی رویه استفاده از کودرادر مزرعه ضروری نموده است. این آزمایش به منظور بررسی تاثیر کودهای بیولوژیک و شیمیایی نیتروژن و فسفر بر عملکرد کمی و کیفی ذرت تحت تنش خشکی انجام شد. بدین منظور، آزمایشی به صورت اسپلیت فاکتوریل با 4 تکرار در قالب طرح بلوک های کامل تصادفی در مردادماه سال 1394 در ایستگاه تحقیقات کشاورزی شهرستان مهران (عرض جغرافیایی 33°07' شمالی و طول جغرافیایی 46°10' شرقی) استان ایلام انجام شد. عامل های موردبررسی شامل آبیاری در 3 سطح شامل عدم تنش (100% ظرفیت زراعی مزرعه ای)، تنش خشکی بر اساس 75% و 50% ظرفیت زراعی (75 و 50% تخلیه رطوبتی از نقطه ظرفیت زراعی) مزرعه؛ کود نیتروژن شامل 100% نیاز کودی به شکل نیتروژن خالص شیمیایی (در سه مرحله قبل از کاشت، ساقه رفتن و گلدهی)، تیمار شاهد و کود بیولوژیک ازتوباکتر به روش تلقیح با بذر؛ کود فسفر شامل 100%نیاز کودی به شکل سوپر فسفات تریپل، تیمار شاهد و کود بیولوژیک سودوموناس که به روش تلقیح با بذر اعمال شد. در کلیه سطوح تنش و مصرف سوپرفسفات تریپل ازتوباکتر موجب افزایش عملکرد دانه نسبت به تیمار شاهد شد، به طوری که در تیمار خشکی 50% ظرفیت زراعی همراه با مصرف سوپرفسفات تریپل و ازتوباکتر، بیشترین عملکرد دانه به مقدار 8093.6 کیلوگرم در هکتار حاصل شد. در تیمار آبیاری کامل همراه با مصرف سوپرفسفات تریپل و ازتوباکتر بیشترین عملکرد پروتئین به مقدار 1105 کیلوگرم در هکتار حاصل شد. در کلیه سطوح تنش و مصرف سوپرفسفات تریپل ازتوباکتر موجب افزایش عملکرد پروتئین نسبت به تیمار شاهد شد، به طوری که در تیمار خشکی 50% ظرفیت زراعی همراه با مصرف سوپرفسفات تریپل، بیشترین عملکرد پروتئین با مصرف ازتوباکتر به مقدار 639.4 کیلوگرم در هکتار حاصل شد. در تیمار تنش خشکی 75% ظرفیت زراعی همراه با مصرف سودوموناس و ازتوباکتر عملکرد پروتئین به مقدار 774.4 کیلوگرم در هکتار حاصل شد که برتر از سایر تیمارها در این سطح تنش بود. به طورکلی نتایج این بررسی نشان داد که سودموناس و ازتوباکتر چه در حالت اعمال تنش با مقدار پایین و چه در حالت اعمال تنش به مقدار زیاد موجب افزایش عملکرد کمی و کیفی گیاه ذرت شدند. به علاوه، می توان نتیجه گرفت که کود زیستی سودوموناس و ازتوباکتر می توانند اغلب موادغذایی موردنیاز ذرت را به ویژه در زمان محدودیت آب تامین کنند.
    کلیدواژگان: ازتوباکتر، پروتئین، تلقیح، سودموناس، عملکرد
  • محمد قاسم جامی، امیر قلاوند، سید علی محمد مدرس ثانوی *، علی مختصی بیدگلی، ابوالفضل باغبانی آرانی، امین نام داری صفحات 141-152
    به منظور بررسی تاثیر تلفیقی منابع مختلف کود نیتروژن (کود آلی و اوره) و زئولیت تحت رژیم های متفاوت آبیاری، بر صفات کیفی دانه آفتابگردان (Helianthus annuus L.)، آزمایشی در سال های 1394-1393 در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه تربیت مدرس به صورت اسپلیت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار اجرا شد. فاکتور اصلی شامل رژیم های آبیاری (آبیاری پس از تخلیه 40، 60 و 80 درصد رطوبت قابل استفاده خاک) بود. ترکیب عامل های فاکتوریل از سامانه های حاصلخیزی خاک و زئولیت شامل تلفیقی از کود آلی (35 درصد مرغی + 65 درصد کود گوسفندی) به عنوان تامین کننده 100 درصد نیتروژن موردنیاز از طریق منبع آلی، تامین 50 درصد نیتروژن موردنیاز از طریق منبع آلی + تامین 50 درصد نیتروژن موردنیاز از طریق اوره، تامین 100 درصد نیتروژن موردنیاز از طریق اوره و عدم کاربرد و کاربرد 5 و 10 تن در هکتار زئولیت بود. به ترتیب در سال اول و دوم، بیشترین قطر (2.2 و 2.26 میلی متر) و ارتفاع (186.7 و 186.3 سانتی متر) ساقه و همچنین عملکرد روغن و پروتئین در سال دوم (943.6 و 556.1 کیلوگرم در هکتار) در شرایط عدم تنش (آبیاری پس از تخلیه 40 درصد رطوبت قابل استفاده خاک) با کاربرد زئولیت حاصل شد. درمجموع می توان نتیجه گرفت که تنش رطوبتی شدید، باعث کاهش درصد اسیدهای چرب غیراشباع (به ترتیب اولئیک اسید و لینولئیک اسید در سال اول 22 و 7 درصد و در سال دوم 27 و 6.8 درصد) و استئاریک اسید (به ترتیب در سال اول و دوم 50 و 52 درصد)، ولی افزایش مقدار پالمتیک اسید (به ترتیب در سال اول و دوم 54.6 و 65.3 درصد) آفتابگردان شد و به ترتیب در سال اول و دوم، کاربرد سیستم حاصلخیزی آلی با افزایش میزان اسید چرب لینولئیک (9.2 و 9.7 درصد) و اولئیک (7.8 و 8.2 درصد) دانه، سبب افزایش کیفیت روغن دانه آفتابگردان گردید که در شرایط آبیاری مطلوب، کودهای آلی و در شرایط تنش کم آبی، کودهای آلی دارای زئولیت دارای مزیت بودند.نتایج این آزمایش نشان داد که در اکثر تیمارهای آبیاری، مصرف زئولیت و کودهای آلی با افزایش دسترسی آب و عناصر غذایی، سبب افزایش عملکرد کمی و کیفی آفتابگردان گردید و نیز ایده مفیدی برای کاهش کاربرد کودهای شیمیایی در راستای کشاورزی پایدار است.
    کلیدواژگان: اسیدهای چرب غیراشباع، پروتئین، تنش کم آبی، روغن، کود آلی
  • حسن قاسمیان اردستانی*، محسن جهان، امیر حسین شیرانی راد صفحات 153-163
    به منظور ارزیابی عملکرد و اجزای عملکرد ژنوتیپ های منتخب کلزا در رژیم های مختلف دمایی و رطوبتی، آزمایشی به صورت فاکتوریل کرت های خرد شده در قالب طرح بلوک های کامل تصادفی با سه تکرار و به مدت دو سال زراعی (95-1393) در منطقه کرج اجرا شد. در این تحقیق، فصل کشت در دو سطح (پائیز و زمستان) و آبیاری در سه سطح (آبیاری معمول یا شاهد، قطع آبیاری از مرحله گلدهی به بعد و قطع آبیاری از مرحله خورجین دهی به بعد) به صورت فاکتوریل به عنوان عامل کرت اصلی و ژنوتیپ های بهاره کلزا شامل جری، جولیوس، ظفر، آرجی اس 003، هایولا 4815 و زابل 10 به عنوان عامل کرت فرعی در نظر گرفته شدند. صفات مورد ارزیابی عبارت بودند از ارتفاع بوته، قطر ساقه، تعداد شاخه فرعی، تعداد خورجین، طول خورجین، تعداد دانه در خورجین، وزن هزار دانه، عملکرد بیولوژیک، عملکرد دانه و شاخص برداشت. همه صفات مورد مطالعه تحت تاثیر تیمارهای آزمایش قرار گرفتند. در رابطه با عملکرد به عنوان برآیند نهایی اجزای عملکرد نتایج نشان داد که کشت پاییزه با عملکرد 3590 کیلوگرم در هکتار نسبت به کشت زمستانه با 2042 کیلوگرم در هکتار برتری داشت، در بررسی اثرات متقابل سه گانه، در کشت پاییزه با شرایط آبیاری معمول (شاهد)، ارقام جولیوس و زابل 10 با عملکرد دانه 5592 و 5536 کیلوگرم در هکتار، در شرایط قطع آبیاری از مرحله گل دهی به بعد ژنوتیپ جولیوس با عملکرد 2511کیلوگرم در هکتار و در شرایط قطع آبیاری از مرحله خورجین دهی به بعد ارقام جولیوس و زابل 10 با عملکرد 4124 و 3959 کیلوگرم در هکتار، ارقام برتر بودند. بطور کلی کشت پاییزه به عنوان بهترین زمان وارقام جولیوس و زابل 10 به عنوان پایدارترین ارقام معرفی گردیدند.
    کلیدواژگان: تاریخ کاشت، تنش خشکی، خورجین، عملکرد بیولوژیک
  • حسین شیرازی *، عباس بیابانی، حسین صبوری، معصومه نعیمی صفحات 165-179
    آب یکی از منابعی است که در تولید محصولات کشاورزی نقش مهمی ایفا می کند به همین منظور بررسی تاثیر مدیریت های آبیاری بر صفات مورفولوژیک و عملکرد ارقام برنج، چهار آزمایش جداگانه هر کدام در قالب طرح بلوک های کامل تصادفی در مزرعه تحقیقاتی دانشگاه گنبد کاووس در سال 1395 انجام شد. تیمارهای آزمایش شامل چهار آزمایش به طور جداگانه در شرایط غرقابی و دورهای آبیاری 5، 10 و 15 بودند. تیمارهای آبیاری چهل روز پس از انتقال نشای ارقام برنج به مزرعه در مرحله حداکثر پنجه زنی اعمال گردید. ارقام کشت شده نیز شامل شش رقم برنج (یک رقم ایرانی دم سیاه و سه رقم IR66424–1-2–1-5،IR70360–38–1-B-1 ، IR 55411-50 و دو لاین در حال معرفی 87.110 و 87.5.103) بود. نتایج تجزیه واریانس و مقایسات میانگین نشان داد که اختلاف معنی داری بین سطوح تیمارهای آزمایشی وجود دارد. اعمال تنش، عملکرد دانه را به طور معنی داری کاهش داد. نتایج مقایسه میانگین در شرایط غرقاب نشان داد، رقم 87.110، کم ترین زمان تا رسیدگی و میزان عملکرد دانه را دارد و عملکرد دانه آن اختلاف معنی داری نسبت به رقم بومی دم سیاه نداشت. در دور آبیاری 5 روزه بیش ترین میزان عملکرد دانه و کم ترین تعداد روز تا رسیدگی در رقم 87.5.103 ملاحظه شد. عملکرد دانه در دور آبیاری 10 روزه رقم IR 55411-50 اختلاف معنی داری را نسبت به سایر ارقام نشان داد، همچنین نتایج نشان داد که رقم 87.5.103 زودرس تر بود. در دور آبیاری 15 روزه با اینکه از رقم 87.110 بالاترین عملکرد دانه حاصل نشد، با رقم دم سیاه نیز اختلاف معنی داری نداشته است، در جمع بندی نتایج حاصل، رقم 87.110 در شرایط دور آبیاری 15 روز زودرس ترین رقم و مناسب کشت در منطقه تعیین شد.
    کلیدواژگان: برنج، دور آبیاری، شاخص برداشت، طول دوره رشد، عملکرد دانه
  • نادیا قره چایی، فرزاد پاک نژاد *، امیر حسین شیرانی راد، قاسم توحیدلو، حمید جباری صفحات 181-195
    به منظور ارزیابی عکس العملهای ژنوتیپ های منتخب پاییزه کلزا به تنش رطوبتی آخر فصل در شرایط کشت تاخیری، آزمایشی به صورت فاکتوریل اسپلیت پلات در قالب طرح بلوک های کامل تصادفی با سه تکرار به مدت دو سال ( 95-94 و 96-95 ) در منطقه کرج اجرا شد. در این آزمایش عامل تاریخ کاشت در دو سطح شامل کشت به موقع (پانزدهم مهرماه) و کشت تاخیری (پنجم آبان ماه)، عامل آبیاری شامل آبیاری معمول و قطع آبیاری از مرحله خورجین دهی به بعد به صورت فاکتوریل در کرت های اصلی و چهار ژنوتیپ کلزا (L1030، L1204، L1110، L1114) و یک رقم تجاری (Okapi)در کرت های فرعی قرار گرفتند. نتایج نشان داد که اثر برهمکنش تاریخ کاشت و ژنوتیپ بر کلیه صفات مورد بررسی به استثنای شاخص برداشت معنی دار شد و بیشترین میانگین صفات در تاریخ کاشت پانزدهم مهرماه و از ژنوتیپ L1204 به دست آمد. در این تحقیق اعمال تنش رطوبتی بعد از مرحله خورجین دهی باعث کاهش عملکرد دانه شد و کمترین میانگین صفات در این شرایط متعلق به ژنوتیپ L1114 بود. در شرایط کشت تاخیری و قطع آبیاری از مرحله خورجین دهی ژنوتیپ L1204 با بالاترین میزان عملکرد دانه (2460 کیلوگرم در هکتار) و عملکرد روغن دانه (1017 کیلوگرم در هکتار) قابلیت کشت و توسعه در این تاریخ کشت و شرایط کم آبی آخر فصل را دارد.
    کلیدواژگان: تاریخ کاشت، عملکرد دانه، قطع آبیاری، مرحله خورجین دهی
  • زهرا طهماسبی *، حسین محمدی ده بالایی صفحات 197-207
    لوبیای سیاه (Phaseolus vulgaris L.) یا Black bean واریته ای از لوبیای معمولی است که دارای خواص آنتی اکسیدانی بالا می باشد. به منظور ارزیابی واکنش 11 ژنوتیپ لوبیا سیاه به همراه 3 ژنوتیپ لوبیا از رنگ های دیگر (به عنوان شاهد) به تنش خشکی، آزمایشی در قالب طرح بلوک های کامل تصادفی در دو شرایط آبیاری نرمال و آبیاری محدود اجرا شد. تنش آبی در مرحله گلدهی اعمال شد. در پایان فصل رشد 5 گیاه از هر ردیف برداشت شد و صفات تعداد غلاف در بوته، تعداد دانه در غلاف، ارتفاع گیاه، عملکرد دانه و وزن 100 دانه اندازه گیری شدند. نتایج تجزیه مرکب و مقایسه میانگین داده ها نشان دادند که کلیه صفات در اثر تنش تحت تاثیر قرار گرفتند و بین ژنوتیپ های مورد بررسی از لحاظ صفات مورد مطالعه در هر دو محیط نرمال آبی و تنش تفاوت معنی داری وجود داشت. از بین شاخص های خشکی، شاخص های STI، HARM و GMP جهت شناسایی ژنوتیپ های متحمل به تنش انتخاب شدند بنابراین بر اساس این شاخص ها از بین ژنوتیپ های لوبیا سیاه، ژنوتیپ 1183 به عنوان متحمل ترین (با عملکرد 8.07 گرم در بوته) و ژنوتیپ های 1187 و 1177 به عنوان حساس ترین ژنوتیپ به تنش خشکی (به ترتیب با عملکرد 4.17 و 5.22 گرم در بوته) انتخاب شدند. همچنین ژنوتیپ های شاهد (256، تلاش و دانشکده) دارای عملکرد بالاتر (به ترتیب 18.72، 13.56 و 14.21 گرم در بوته) و از نظر اکثر شاخص ها مقاوم تر از ژنوتیپ های لوبیای سیاه بودند.
    کلیدواژگان: اجزای عملکرد، تجزیه مرکب، شاخص های تحمل خشکی، عملکرد
  • مژده عقیلی لاکه، الیاس سلطانی *، ایرجاللهدادی، فاطمه بناکاشانی صفحات 209-221
    هدف از این تحقیق ارزیابی ژنوتیپ‏های مختلف کلزا در واکنش به تنش‏های دمایی مختلف بود. با استفاده از دماهای اصلی (کاردینال) شاخص های تحمل به دمای بالا و پایین تعیین گردید. سپس، ژنوتیپ‏های مختلف از این نظر ارزیابی شدند. به این منظور آزمایش جوانه‏ زنی با 3 تکرار 50 بذری در درون اتاقک (انکوباتور)های رشد با دماهای ثابت 5، 10، 15، 20، 25 و 30 درجه سانتی‏گراد روی 10 ژنوتیپ کلزا انجام گرفت. در نهایت، پاسخ سرعت جوانه‏زنی به دما با تابع دوتکه ای و درصد جوانه‏زنی با تابع بتا توصیف شد. با کمک دماهای اصلی برای درصد و سرعت جوانه‏زنی، تحمل به دماهای بالا و پایین برای ژنوتیپ‏های مختلف تعیین شد. نتایج نشان داد که میانگین دماهای کمینه، بهینه و بیشینه برای درصد جوانه‏ زنی به‏ ترتیب برابر 4.99، 18.23 و 34.20 درجه سانتی‏گراد بود و همچنین میانگین دماهای کمینه، بهینه و بیشینه برای سرعت جوانه‏ زنی به ‏ترتیب برابر 6.18، 24.76 و 39.43 درجه سانتی‏گراد بود. شاخص ‏های تحمل به گرما و سرما نیز میان ارقام مختلف متفاوت بودند. رقم اکاپی هم در شاخص تحمل به گرما (5.95) و هم در تحمل به سرما (8.48) متحمل‏ترین رقم شناخته شد. رقم ایکس پاور پایین ترین تحمل را هم در شاخص‏های تحمل به گرما (4.78) و هم به سرما (6.50) داشت. همچنین، پتانسیل القای خفتگی ثانویه ناشی از تنش خشکی در رقم اکاپی (حدود 40%) در بالاترین مقدار نسبت به سایر ارقام بود. به نظر می‏رسد، ارتباطی بین پتانسیل القای خفتگی ثانویه و تحمل به تنش‏های دمایی وجود داشته باشد که نیاز به مطالعه بیشتر دارد.
    کلیدواژگان: تابع بتا، تابع دوتکه‏ ای، تنش دما، دماهای کاردینال
  • پیمان عینی زاده، حمید دهقانی *، مصطفی خدادادی صفحات 223-237
    گشنیز گیاهی یک ساله بوده که مانند هر گیاه زراعی دیگری عملکرد آن تحت تاثیر تنش خشکی قرار می گیرد. این پژوهش به منظور بررسی توده های بومی گشنیز از لحاظ صفات مرتبط با عملکرد و محتوای اسانس میوه و پیشنهاد دو روش گزینش گرافیکی برای ارتقاء چندین صفت کمی و کیفی به طور هم زمان در رژیم های مختلف آبیاری انجام شد. برای این منظور سه آزمایش در رژیم های آبیاری نرمال، تنش خشکی یکباره و تنش خشکی تدریجی هر کدام در قالب طرح بلوک های کامل تصادفی با سه تکرار اجرا شد.نتایج نشان داد گزینش بر اساس محتوای کلروفیل و تعداد برگ پایه می تواند به طور هم زمان دو صفت اقتصادی عملکرد میوه و محتوای اسانس میوه را بهبود ببخشد. همچنین گزینش درون اکوتیپ 9 (بوشهر) برای کشت دیم و تولید میوه و اسانس در مناطق دارای تنش خشکی انتهای فصل و گزینش بوته های برتر اکوتیپ 10 (آذربایجان غربی)برای مصرف تازه خوری و تولید میوه و اسانس در شرایط نرمال توصیه شد. گزینش درون اکوتیپ های 3 (فارس)، 4 (اصفهان)، 11 (لرستان)، 14 (اصفهان) و 15 (فارس) و تشکیل جمعیت می تواند در بهبود هم زمان صفات مهم اقتصادی مانند عملکرد اسانس میوه، تعداد برگ پایه و وزن خشک زیست توده، در شرایط آبیاری نرمال و تنش خشکی موثر باشد.
    کلیدواژگان: بای پلات ژنوتیپ در صفت، تنش تدریجی، تنش یکباره، تنش خشکی، گزینش هم زمان
  • مهدی کریمی * صفحات 239-249
    چگونگی تاثیر تنش شوری بر نیاز غذایی گیاهان یکی از چالش های تغذیه گیاهی می باشد. در برخی از منابع، مصرف بیشتر کودهای شیمیایی از جمله کودهای نیتروژنی، فسفری و پتاسیمی در شرایط شور نسبت به شرایط غیر شور توصیه شده است. اما، در برخی دیگر از منابع، مصرف کمتر و یا مصرف یکسان کود در شرایط شور و غیر شور پیشنهاد شده است. پژوهش اخیر در راستای بررسی نیاز کودی گندم (رقم بم) در شرایط مختلف شوری آب آبیاری در مزرعه تحقیقاتی مرکز ملی تحقیقات شوری واقع در یزد اجرا شد. این تحقیق دارای سه سطح شوری آب آبیاری 1.88، 7.22 و 14.16 دسی زیمنس بر متر و چهار سطح کود سولفات پتاسیم شامل صفر، 100، 200 و 300 کیلوگرم در هکتار بود. آزمایش در قالب طرح آماری بلوک های کامل تصادفی به صورت اسپلیت پلات با سه تکرار اجرا شد. نتایج نشان داد که با افزایش شوری آب آبیاری از 1.88 به 7.22 دسی زیمنس بر متر، عملکرد دانه و کاه گندم کاهش معنی داری نداشت. با افزایش شوری آب آبیاری به 14.16 دسی زیمنس بر متر، عملکرد دانه و کاه حدود 50 درصد کاهش یافت. بررسی اثرات متقابل شوری و کود سولفات پتاسیم نشان داد که مصرف کود سولفات پتاسیم تاثیر معنی داری بر عملکرد دانه و کاه گندم در هیچیک از سطوح شوری مورد مطالعه نداشت. بنابراین، فرضیه افزایش تحمل به شوری گندم با مصرف کود پتاسه در شرایط مزرعه ای این تحقیق مردود شد. به طور کلی، برای تولید حدود 6 تن دانه و 9 تن کاه گندم در شرایط گرم و خشک استان یزد و در خاک آهکی با پتاسیم قابل جذب معادل 150 میلی گرم در کیلوگرم خاک که با آب با هدایت الکتریکی 1.88 تا 14.16 دسی زیمنس بر متر آبیاری شود مصرف کود سولفات پتاسیم ضرورتی ندارد.
    کلیدواژگان: آب آبیاری، خاک آهکی، یزد
  • عادل مدحج *، اعظم کربلایی صفحات 251-262
    به منظور بررسی اثر برهمکنش شوری و دما بر جوانه زنی و رشد گیاهچه سه ژنوتیپ گندم نان و دوروم، آزمایشی در سال 93-1392 در آزمایشگاه تخصصی واحد علوم تحقیقات خوزستان در محیط کشت پتری دیش انجام شد. آزمایش به صورت فاکتوریل در قالب طرح کاملا تصادفی و چهار تکرار با سه فاکتور دما (15/10، 25/20 و 35/30 درجه سانتی گراد به ترتیب شب و روز)، ژنوتیپ های گندم (دو ژنوتیپ نان شامل رقم چمران و لاین 20 سراسری و لاین دوروم D85-17) و شوری (صفر، دو، چهار، هشت و 12 دسی زیمنس بر متر) اجرا شد. نتایج نشان داد که افزایش شوری باعث کاهش معنی دار درصد جوانه زنی در ژنوتیپ های گندم شد. ژنوتیپ های گندم در دمای 25/20 درجه سانتی گراد بیشترین رشد گیاهچه را به خود اختصاص دادند. بیشترین و کمترین درصد جوانه زنی در دمای 15/10 و 35/30 درجه سانتی گراد مشاهده شد. لاین دوروم D85-17 در مقایسه با دو ژنوتیپ نان حساسیت بیشتری نسبت به شوری و دما داشت. افزایش دمای محیط، اثر شوری بر جوانه زنی و رشد گیاهچه را تشدید کرد. افزایش دما موجب تشدید اثر شوری بر طول ساقه چه شد به نحوی که میزان کاهش طول ساقه چه در شوری 12 دسی زیمنس نسبت به شاهد آب مقطر در دماهای 15/10، 25/20 و 30/35 به ترتیب 33.3، 50 و 84 درصد بود. نسبت سدیم به پتاسیم در گیاهچه ژنوتیپ های گندم در دماهای بالا افزایش یافت. لاین دوروم D85-17از نسبت سدیم به پتاسیم و حساسیت بیشتر به شوری در مقایسه با دو ژنوتیپ نان برخوردار بود.
    کلیدواژگان: پتاسیم، سدیم، شوری، ریشه‎چه
  • مائده بهلولی، مریم دهستانی اردکانی*، مصطفی شیرمردی، جمشید رزم جو صفحات 263-280
    شوری یکی از تنش های مهم محیطی محدودکننده رشد گیاهان است و کاربرد مواد آلی و قارچ های میکوریزا آربوسکولار سبب کاهش اثرات سوء آن می شود. هدف از این مطالعه، بررسی اثر سطوح مختلف شوری و اصلاح کننده های بیولوژیکی و آلی بر برخی ویژگی‏های رشدی در گل مغربی (Oenothera biennis L.) بود. آزمایش به صورت فاکتوریل در قالب طرح کاملا تصادفی با شش سطح از مواد اصلاحی شامل شاهد (بدون مواد اصلاح کننده)، 1.5 و 3 گرم قارچ میکوریزا در هر کیلوگرم خاک، 16 و 32 میلی‏گرم اسید هیومیک در یک لیتر آب آبیاری و 25 درصد حجمی گلدان بقایای گیاهی روناس در سه سطح شوری خاک (4، 7 و 12 dSm-1) با سه تکرار اجرا شد. نتایج نشان داد که با افزایش شوری، شاخص های رشدی و غلظت عناصر غذایی به طور معنی داری کاهش یافت. در هدایت الکتریکی dSm-1 4 بیشترین ارتفاع گیاه، طول ریشه و غلظت فسفر در تیمار g/kg 3 قارچ میکوریزا به دست آمد که به ترتیب نسبت به شاهد 16.72، 48.76 و 61.11 درصد بیشتر بود. در هدایت الکتریکی dSm-1 7 بیشترین میزان کلروفیل، ارتفاع گیاه، وزن خشک شاخساره و نسبت وزن خشک به تر در تیمار g/kg 1.5 قارچ میکوریزا به دست آمد که به ترتیب نسبت به شاهد 7.34، 18.19، 29.21 و 29.16 درصد بیشتر بودند. همچنین بقایای گیاهی روناس غلظت سدیم را در سطح شوری 7 دسی زیمنس بر متر، 42.79 درصد نسبت به شاهد کاهش داد. در هدایت الکتریکی dSm-1 12 بیشترین میزان کلروفیل، وزن خشک شاخساره، تعداد برگ فعال و سریع ترین زمان گلدهی در تیمار بقایای گیاه روناس به دست آمد که به ترتیب نسبت به شاهد 16.12، 58.96، 51.14 و 100 درصد بیشتر بودند. رشد زایشی گیاهان در شوری dSm-1 12 (شاهد) متوقف شد اما استفاده از کودهای آلی و بیولوژیک موجب گل دهی آن ها شد. به طورکلی همه تیمارهای کود آلی و بیولوژیکی در تمام سطوح شوری موجب بهبود رشد و عملکرد گیاه شدند.
    کلیدواژگان: اسید هیومیک، پتاسیم، روناس، سدیم، قارچ میکوریزا
  • ریحانه پردل، محمد کافی *، مسعود اصفهانی، احمد نظامی صفحات 281-289
    عصاره خام گیاه استویا حاوی ماده شیرین کننده ای است که از برگ های این گیاه بدست می آید و به عنوان یک شیرین کننده کم کالری مورد استفاده قرار می گیرد. این آزمایش گلدانی با هدف مطاالعه اثر سطح تنش غرقاب ، مدت غرقاب و کود نیتروژن بر رشد اندام های هوایی گیاه استویا در دانشگاه گیلان در سال 1392 انجام شد. آزمایش بصورت فاکتوریل در قالب طرح کاملا تصادفی با سه تکرار انجام شد. سطوح تنش غرقاب شامل (صفر، 5- و 10- سانتی متر از سطح خاک و آبیاری نرمال بر اساس نیاز گیاه به عنوان شاهد)، مدت غرقاب ( دو و چهار روز) و دو سطح کودی شامل (صفر و شش در هزار محلول نیتروژن با منشا اوره) به صورت محلول پاشی بود. نتایج نشان داد که کاربرد کود نیتروژن در شرایط تنش غرقاب منجر به بهبود صفات اندازه گیری شده شامل ارتفاع، درصد برگ، وزن مخصوص برگ و وزن خشک برگ شد. برهم کنش کود نیتروژن و مدت غرقاب نشان داد که با افزایش مدت غرقاب از دو روز به چهار روز کاربرد کود نیتروژن منجر به بهبود %14 وزن خشک برگ، %11 وزن مخصوص برگ و 4.5% برگی بودن نسبت به تیمار عدم کاربرد کود شد. همچنین برهم کنش کود نیتروژن و سطح غرقاب نیز نشان داد که در سطح غرقاب 10- سانتی متر، کاربرد کود نیتروژن منجر به کاهش اثرات نامطلوب تنش شد به طوری که کاهش تعداد شاخه های جانبی و میزان وزن خشک برگ در سطح غرقاب 10- و بدون کاربرد کود نیتروژن در مقایسه با تیمار کاربرد کود نیتروژن به ترتیب نه و هشت درصد بیشتر بود. به طور خلاصه نتایج این آزمایش نشان داد که کاربرد کود نیتروژن در شرایط تنش غرقابی منجر به بهبود رشد اندام های هوایی استویا و کاهش اثر تنش غرقابی در گیاه استویا در شرائط رشت می شود.
    کلیدواژگان: برگ استویا، سطوح نیتروژن، وزن خشک، وزن ویژه برگ
  • بصیر عطاردی، رضا خراسانی، پیمان کشاورز، امیر فتوت* صفحات 291-305
    بر اساس برخی گزارشات، متوسط کادمیم در برخی خاک ها و محصولات زراعی ایران از مقادیری که توسط سازمان خوار و بار کشاورزی و سازمان بهداشت جهانی به عنوان سطح مجاز معرفی شده، بیشتر می باشد. در دهه های اخیر، به منظور کاهش اثرات مخرب کادمیم در گیاهان استفاده از عناصری نظیر سلنیم که خاصیت آنتاگونیستی با کادمیم دارند مورد توجه قرار گرفته اند. پژوهش حاضر با هدف بررسی پاسخ گیاه گندم (رقم فلات) به مصرف سلنیم در شرایط تنش کادمیم انجام شد. به این منظور، آزمایشی به صورت فاکتوریل در قالب طرح کاملا تصادفی در سه تکرار و در شرایط گلدانی در گلخانه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی اجرا گردید. فاکتورهای آزمایشی شامل چهار سطح سلنیم (0، 5/0، 1 و 4 میلی گرم بر کیلوگرم) و سه سطح کادمیم (0، 5 و 15 میلی گرم بر کیلوگرم) بود. صفات مورد بررسی شامل غلظت کلروفیل a، b، کاروتنوئید، پرولین، فعالیت آنزیم کاتالاز و وزن خشک ساقه بود. نتایج نشان داد با افزایش غلظت کادمیم در خاک، محتوی رنگدانه های فتوسنتزی و فعالیت آنزیمی گندم کاهش ولی میزان پرولین افزایش یافت. در مقابل، گیاهانی که در معرض تنش کادمیم قرار داشتند و هم زمان غلظت های کمی از سلنیم نیز دریافت کردند در مقایسه با گیاهان مشابه که سلنیم دریافت نکردند محتوی کلروفیل b و فعالیت آنزیمی بیشتری داشتند. با این وجود، سلنیم تاثیر مثبتی بر غلظت کاروتنوئید، کلروفیل a و وزن خشک ساقه گندم نداشت. ضمنا غلظت های زیاد سلنیم نه تنها تاثیر سودمندی بر صفات مورد بررسی نداشت بلکه باعث کاهش غلظت رنگدانه های فتوسنتزی، فعالیت آنزیمی و وزن خشک ساقه گردید. در مجموع می توان نتیجه گیری کرد که در شرایط تنش کادمیم، مصرف غلظت های مناسبی از سلنیم باعث بهبود برخی پارامترهای فیزیولوژیکی گندم می گردد.
    کلیدواژگان: آنتاگونیست، رنگ دانه های فتوسنتزی، سلنیم، عناصر سنگین، کاتالاز
  • زهرا قربان پور، احمد غلام علی زاده آهنگر *، امیر لکزیان، ابولفضل عباس پور صفحات 307-317
    کادمیوم از فلزات سنگین و عنصری سمی برای گیاهان است که از طریق فعالیت های مختلف بشر وارد خاک می شود. به منظور بررسی تاثیر استفاده از کودهای کلرور و سولفات پتاسیم بر جذب کادمیوم و ارتقای گیاه پالایی آن توسط گیاه کلزا (Brassica napus. L) رقم مدنا، آزمایشی به صورت فاکتوریل و در قالب طرح کاملا تصادفی با 4 سطح پتاسیم (صفر، 100، 200 و 300 میلی گرم پتاسیم در کیلوگرم) از منابع کلرور و سولفات پتاسیم به طور جداگانه و 3 سطح کادمیوم (صفر، 15 و 30 میلی گرم کادمیوم در کیلوگرم) از منبع نیترات کادمیوم در سه تکرار، در گلخانه مرکز تحقیقات مشهد انجام شد. با توجه به نتایج تجزیه واریانس اثرات کادمیوم و کودهای پتاسیم و برهمکنش آن ها بر مقدار کادمیوم ریشه و اندام هوایی، وزن خشک و پتاسیم ریشه اثری معنی دار داشت (p<0.01). هم چنین بر اساس نتایج، اثرات اصلی کودهای پتاسیم و کادمیوم بر وزن خشک و پتاسیم اندام هوایی اثر معنی داری داشت (p<0.01)، درحالی که اثر برهمکنش آن ها بر وزن خشک و پتاسیم اندام هوایی معنی دار نشد. هم چنین کاربرد کادمیوم نشان داد که با افزایش کادمیوم، پتاسیم اندام هوایی به طور معنی داری کاهش یافت و در تمام سطوح پتاسیم کاهش معنی داری را نشان دادند. در این بررسی بین کودهای پتاسیم تفاوت معنی داری مشاهده شد، به طوری که بالاترین مقدار جذب کادمیوم با مصرف 300 میلی گرم پتاسیم در کیلوگرم به صورت کلرور پتاسیم به دست آمد. بنابراین بر اساس نتایج آزمایش گلخانه ای با مصرف کود کلرور پتاسیم کارایی گیاه پالایی بهبود یافت اگرچه تداوم تحقیقات در شرایط مزرعه ضروری به نظر می رسد.
    کلیدواژگان: فلز سنگین کادمیوم، کود پتاسیم، گیاه پالایی، گیاه کلزا
  • امید صادقی پور* صفحات 319-329
    به منظور بررسی مقایسه ای اثر پیش تیمار بذر لوبیا چیتی با پرولین و گلایسین بتائین در تحمل به تنش سرب آزمایشی گلدانی در بهار و تابستان سال 1394 انجام شد. این تحقیق به صورت طرح کاملا تصادفی با شش تیمار و چهار تکرار اجرا گردید. تیمارها عبارت بودند از: شاهد، تنش سرب (500 میلی گرم بر کیلوگرم خاک نیترات سرب)، تنش سرب + پیش تیمار بذر با محلول 25 میلی-مولار پرولین، تنش سرب + پیش تیمار بذر با محلول 50 میلی مولار پرولین، تنش سرب + پیش تیمار بذر با محلول 25 میلی مولار گلایسین بتائین و تنش سرب + پیش تیمار بذر با محلول 50 میلی مولار گلایسین بتائین. نتایج نشان داد که تنش سرب موجب افزایش غلظت سرب ریشه و خسارت اکسیداتیو به بوته های لوبیا گردید. سمیت سرب همچنین موجب کاهش شاخص سبزینگی، محتوی نسبی آب، ارتفاع بوته، سطح برگ و زیست توده ریشه و اندام هوایی شد. با این وجود، در شرایط تنش سرب، پیش تیمار بذر با پرولین یا گلایسین بتائین موجب کاهش جذب سرب، افزایش فعالیت آنزیم های آنتی اکسیدانت و کاهش خسارت اکسیداتیو گردید که باعث بهبود شاخص سبزینگی، محتوی نسبی آب، ارتفاع بوته، سطح برگ و زیست توده ریشه و اندام هوایی شد. بین تیمارهای مختلف کاربرد پرولین و گلایسین بتائین اختلاف معنی داری مشاهده نشد. براساس یافته های این پژوهش، پیش تیمار بذر با پرولین یا گلایسین بتائین می تواند از طریق کاهش جذب سرب، افزایش فعالیت آنزیم های آنتی اکسیدانت و بهبود شاخص سبزینگی و وضعیت آبی گیاه، به عنوان روشی مفید در بهبود تحمل به تنش سرب در لوبیا مورد استفاده قرار گیرد.
    کلیدواژگان: آنزیم های آنتی اکسیدانت، شاخص سبزینگی، فلزات سنگین، محلول های سازگار
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  • Ali Mahrokh *, Majid Nabipour, Habib Alah Roshanfekr, Rajab Choukan Pages 1-15
     
    Introduction
    Drought is one of the major environmental conditions that adversely affect plant growth and crop yield. In the face of a global scarcity of water resources, water stress has already become a primary factor in limiting maize production worldwide. It’s because Phytohormones such as auxin and cytokinin are reported to be involved in the regulation of plant response to the adverse effect of drought stress conditions. This study carried out in order to evaluate some physiological parameters response to auxin and cytokinin hormone alternation under drought stress condition on maize (cultivar KSC 704).
    Materials and Methods
    The experiment was carried out in three separately environments included non-drought stress environment (irrigation after soil moisture reached to 75% field capacity), drought stress in vegetative stage (irrigation after soil moisture reached to 50% field capacity in V4 to tasseling stage, but irrigation after soil moisture reached to 75% field capacity in pollination to physiological maturity stage) and drought stress in reproductive stage (irrigation after soil moisture reached to 75% field capacity in V4 to tasseling stage and irrigation after soil moisture reached to 50% field capacity in pollination to physiological maturity stage). cytokinin hormone in three levels (control, spraying in V5 –V6 and V8-V10 stages) and auxin hormone in three levels (control, spraying in silk emergence stage and 15 days after that) was laid out as a factorial design based on randomized complete block with three replications in each environment at Seed and Plant Improvement Institute (SPII), Karaj, Iran, in 2013. It was used Indole-3-butyric acid and N6-benzyladenin as auxin and cytokinin hormones respectively. Concentration of used auxin and cytokinin hormones were 10 and 50 mg per liter respectively. In this study some physiological parameters were measured including leaf area index, cell membrane stability, leaf chlorophyll content, stomata conductive, canopy temperature depression, photosynthesis quantum efficiency and leaf senesce.
    Results and Discussion
    The maximum leaf area index, stomata conductance and quantum efficiency of photosynthesis and the minimum canopy temperature were obtained with spraying cytokinin hormone in V8-V10 stage, and the maximum chlorophyll content index, quantum efficiency of photosynthesis and the delay in leaf senescence were obtained with spraying auxin hormone in silk emergence stage and the minimum stomata resistance and canopy temperature were obtained with spraying cytokinin hormone in 15 days after silk emergence stage. The interaction effect between drought stress and spraying hormone was significant on leaf area index and canopy temperature depression and spraying hormones on maize in drought stress condition in reproductive stage more effective than non-drought stress and vegetative drought stress conditions because it can be useful in balancing the disturb hormone relations.
    Conclusion
    Based on the result of this experiment, maize is tolerant to drought stress in vegetative stage, as a result, irrigation after soil moisture reached to 50% field capacity in vegetative stage and irrigation after soil moisture reached to 75% field capacity after tasseling stage can save irrigation water without any decrease significantly in physiological parameters at erase where water has been limited. Spraying cytokinin and auxin hormones in V8 –V10 and silk emergence stage can be recommended as the best time to use these hormones respectively. Using auxin and cytokinin hormones under drought stress condition in maize was more effective than control and vegetative stage because they can balance the disturbed hormones rate under that condition.
    Keywords: Canopy temperature, chlorophyll, Hybrid 704, Photosynthesis quantum efficiency, Stomata conductive
  • Seyed Mohammad Javad Bahrololomi *, Mahmoud Raeini Sarjaz, Hemmatollah Pirdashti Pages 17-28
     
    Introduction
    Environmental stresses, in addition to their straight effects on plants growth and development, induce oxidative stresses on plants. These secondary stresses cause degradations on cell wall lipids and cell organelles proteins. In response to overflow of reactive oxygen species (ROS) enzymatic and non-enzymatic antioxidants productionscould be induced in plants. Due to the kind and intensity of environmental stressesand plant physiological pathways the activity responses of antioxidant enzymes could be different. Therefore, the aim of this research was to evaluate the effect of water stress on soybean antioxidants induction.
    Materials and Methods
    This trial was done on spring and summer 2012 in Sari Agricultural Sciences and Natural Resources University (SANRU) research station, Sari, Iran. The JK variety of soybean (Glycine max L.), which is widely cultivated in the region was selected for this purpose. A completely randomized design with 4 soil available water (AW) treatments in a pot experiment was employed. After 4-leaf stage soybean seedlings were randomly assigned to 4 water treatments of control, with 100 percent (well-watered, W0), 60 percent (mild stressed, W1), 40 percent (intermediate stressed, W2) and 20 percent (severe water stressed, W3) of soil AW. Plants were re-watered to 100 percent AW upon reaching to the assigned water level. During the R4 and R5 reproductive stages leaf samples were collected to measure leaf catalase and peroxidase enzymes and MDA and leaf total nitrogen and seed weight per plant using spectrophotometer and autoanalyzer. Data were analyzed using SAS software and mean comparisons were done using Tukey post-hoc test.
    Results and discussion
    Findings of this research showed that water stress significantly (p ≤ 0.05) affected leaf enzymatic activities of catalase and peroxidase, and influenced malondialdehyde (MDA) and total nitrogen contents and seed weight per plant. The catalase enzyme activity increased up to 60% AW, Then declined by further increase in soil available water. A highly significant quadratic relation (R2 = 0.89; P ≤ 0.01) was found between this enzyme activity and soil available water. The trend of variations in peroxidase activity by reduction in soil AW was highly positive and significant (P ≤ 0.01). The amount of this enzyme in water stressed treatments relative to control increased by 18.7, 29.9 and 34.4 percent, respectively. A highly significant, but negative correlation (r = - 0.86; P≥0.01) was found between MDA values and soil available water. The variation trend of leaf soluble proteins relative to soil available water was decreasing and significant differences were found between control and stressed treatments of W2 and W. The leaf total nitrogen contents increased by reduction in soil available water (r = 0.84; P ≤ 0.01). Also, seed weight per plant as an index of plant performance up to 60% of available water was ascending and in the moisture content of 80% available water, due to the increasing trend of all antioxidants to the highest.
    Conclusion
    It could be concluded from these findings that increase of antioxidant enzymes, due to mild water stress, could diminish destructive effects of reactive oxygen species (ROS) in soybean. Antioxidant activities to a certain level of water stress, in this case up to 60% of AW, had an effective protective effect on photosynthesis process, therefore on soybean seed yield. It seems catalase activity was more effective on severe water stresses compared with peroxidase enzyme.
    Keywords: Available water, Catalase, Peroxidase, ROS
  • Hamdollah Eskandari *, Ashraf Alizadeh, Amraie, Kamyar Kazemi Pages 29-40
     
    Introduction
    Intercropping, defined as planting two or more crops simoultanously in a same field during a specific growing season, is an agronomical operation which has important advantages such as improving water use efficiency, increasing land use efficiency and yield compared with sole crop systems. Because of lowering available water for agronomical operations, water conservation methods are in high importance in agronomical systems. Partial root zone irrigation has been considered during recent years. In this method, half of root system is irrigated and other half is subjected to dry soil. In wheat maize intercropping it has been reported that partial root zone irrigation improved water use efficiency (Yanh et al., 2011). The purpose of this experiment was evaluating the effect of water deficit induced by partial root zone irrigation in growth and grain yield of maize and mung bean in intercropping and sole cropping systems to assess the possibility of improving water use efficiency.
    Materials and Methods
    The experiment was conducted as a field experiment during 2016-17 growing season in Lorestan province. A tw-factors factorial experiment based on randomized complete block design with three replications was employed to compare the treatments. The fist factor was irrigation (including conventional irrigation (I1) and partial root zone irrigation (I2)) which was applied after seedling establishment. The second factor was planting pattern including sole maize, sole mung bean, within-row intercropping and between-row intercropping. Water consumption and leaf area index were measured during growing period. At harvest time, grain yield and yield components were determined. Water use efficiency was measured by dividing grain yield on water consumption. Land equivalent ratio was used to evaluate the advantage of intercropping.
    Results and Discussion
    The highest grain yield of maize was recorded in sole cropping system under conventional irrigation. The lowest grain yield of maize was achieved in between-row intercropping under partial root zone irrigation. There was a reduction in grain yield with lowering water availability. Leaf area index of maize in partial root zone irrigation system was lower than that of conventional irrigation. Partial irrigation reduced all yield component of maize including grain number and weight. However, the effect of water deficit on grain weight was more than grain number. Lower plant number per unit area can be considered as a cuase of the lower grain yield of maize in between-row intercropping. Furtheremore, reducing leaf area index under partial root zone irrigation showed a reduction in leaf size and number, resulting in lower solar radiation absorption and, finally, reduction of photo assimilates synthesis.
    The highest yiel of mung bean was achieved under conventional irrigation and sole cropping system which was not significanlt difference with within-row intercropping. Mung bean produced the lowest grain yield in between-row intercropping in partial root zone irrigation. Generally, partial root zone irrigation reduced mung bean grain yield in all treatments with the amount of 29%, 22% and 21% for soel cropping, between-row intercropping and within-row intercropping, respectively.
    Although the highest grain yield was achived from maize sole cropping under conventional irrigation, the highest waer use efficiency of this treatment was lower than that of sole maize and within-row maize-mung bean intercropping. In all treatment, water use efficiency was improved by applying the partial root zone irrigation system which its highest value was recorded for maize-mung eban intercropping (43%) and mung bean sole cropping (39%). Land equivalent ratio of both interropping systems under partial and conventional irrigation was more than one, indicating the advantage of intercropping. The advantage of within-row intercropping under both irrigation systems was two times more than that of sole cropping.
    Conclusion
    Yield and yield components of maize and mung bean were reduced under partial root zone irrigation due to the reduction of grain weight and number. Reduction of water consumption through partial root zone irrigation improved water use efficiency. The results of this experiment revealed that maize mung bean intercropping under partial root zone irrigation can produce optimum grain yield while improving water use efficiency.
    Keywords: Land equivalent ratio, Limited irrigation, Water use efficiency
  • Mohsen Rezaei, Hoosein Sabouri *, Abdollatif Gholizadeh, Rahmatollah Mohammadi Gonbad Pages 41-54
     
    Background
    Barley (Hordeum vulgare L.) is one of the most important cereals in the world. Drought is one of the most important abiotic stress and severely limits the production of barley around the world. Diversity is the basis of all screenings and genotypic selection also needs diversity. The use of haplotypes in the study of genetic relationships is important. This is more important when there is little indication of the power of the individual's markers, or when there are several genetic markers in the selected QTLs. Association analysis and study of the relationship between molecular markers and agronomic traits have several applications, including the possibility of studying the genetic potential of specific genotypes before phenotyping, identifying alleles related to traits in the germplasm, facilitating locating QTLs and validation of candidate genes responsible for quantitative traits. The aim of this experiment was to investigate the allelic variation, association analysis and haplotypes of continuous microsatellite markers to drought tolerance genes in the barley.
    Materials and methods
    The experiments were carried out as an augmented design with 96 barley genotypes along with four controls. 18 traits were evaluated on the plants. Then, to evaluate the allelic and haplotypic diversity, the genotypes were tested using five microsatellite markers related to drought tolerance. In the end, phenotypic information was compared with genotypic information, and the relationship between them was determined by linear forward regression.
    Findings
    The analysis of the data obtained from the markers revealed that there were 26 multivariate alleles and also an average of 3.429 alleles for each marker, with the highest number of GBMS180, GMBS183 and EBmac0755 markers with 6 alleles. The results of the PIC show the highest value of the GBMS180 marker and the lowest value of the Bmag0782 marker; the mean of PIC was also 0.6267. The genetic diversity was also between 0.7117 and 0.7602 with an average of 0.6807. The GBMS180 has the highest value and the Bmag0782 has the lowest value. Haplotype evaluation of microsatellite markers on 96 genotypes studied genotypes in fifty-eight haplotype groups, among which the third haplotype group had the most sub cluster with three genotypes. The nineteen group, which included genotype 134, with the highest yield and drought tolerant, with 5183.333 kg ha-1. The results of the coupling analysis indicated that the GMBS183-D allele was involved in controlling four traits of the number of spikes, spike weight, number of seeds per spike and yield, and had the greatest effect among other alleles on the increase or decrease in yield and its components.
    Discussion
    Linear regression and haplotype studies did not overlap, although the forward linear regression of alleles was studied individually and the allelic groups were able to interact with each other, but the obtained data did not have two match methods. But a comparison of the results of allelic variation was similar to linear regression and showed GMBS183, which had the highest PIC, among four attributes related to yield and its components in controlling the three traits of the number of spikes, number of seeds per spike and yield. This marker was also present in control of days to physiological reppining, which plays an important role in plant escape from the stresses, especially drought stress, and R2 is equivalent to 15.4%. This suggests that the results of linear regression match the results of the allele variation and overlap each other.
    Keywords: Barley, Dryness, Haplotype, PIC, QTL, Relationship Analysis
  • Mehdi Kakaei* Pages 55-74
     
    Introduction
    Drought stress and water availability restrictions have always been the most important issue in agriculture in the world and Iran, and this is the most important factor in reducing plant production and Determination and identification of effective factors on wheat seed yield under water deficient condition is very important.
    Iran with were an average rainfall of 240 mm per year is among the arid and semi-arid areas of the world, with this precipitate, the main factor influencing the plant's performance is drought stress. In dry and semi-arid regions due to peripheral dryness and available moisture constraints, the yield of wheat plants decreases dramatically. According to meteorologists, dry weather can occur when rainfall is less than the average of long-term rainfall in a long period of time. However, from the agricultural point of view, if the distribution of rainfall is so low that it causes a significant reduction in the yield of plants, then land has occurred. Considering the importance of wheat as an important and strategic product in Iran, due to the droughts that are occurring (precipitation below the normal level), The purpose of this study was to study the response of some cultivars of genotypes in Asadabad city to the end of the drought stress, identification of higher yield genotype (s) and also determining the characteristics that affect the yield of the present research.
    Material and method
    In order to This study was designed to investigate the genetic diversity and relationships between yield and related other traits (Study of irrigation and correlation of some physiomorphological traits with wheat yield) in 17 wheat genotype and were investigated at completely randomized design with three replications in 2009-2010 under two conditions (drought stress and non-drought stress). An experiment was conducted at the experimental field of the payame Noor University of Asadabad and the agricultural group laboratory located at the provincial lab. Each plot consisted of 5 lines 2 meters long with a distance of 20 cm and a plot distance of 50 cm. Irrigation was carried out in conditions without drought stress according to the custom of the area, However, under irrigation conditions, irrigation was not done and weed combat was carried out manually and in one step (the first stage of stemming). The harvest took place in the middle of July 2011. In order to carry out notes on the study of traits, five genotypes were randomly selected in each replicate. 14 agro-morphological traits were including (Yield stress, Yield potential, Number of Seed Per Spike, Spike Length, Flag leaf Length, Width leaf Length, 100 Kernel Weight, Plant Height, Relative Water Content, Relative Water Loss, SPAD, Area flag leaf and Single Seed weight) measured.  
    Result and discussion
    Analysis of variance revealed good differences among genotypes for two condition drought stress and non-drought stress. Among the traits, the highest coefficient of phenotypic variation was observed for seed yield with SPAD (drought stress condition) and seed yield with Relative Water Loss. Cluster analysis subdivided the genotypes into 3 groups. The maximum distance were observed between the genotype from groups 1 and 3. According to the comparison of mean grain yield, genotypes 7, 8 and 13 showed high yield under moisture conditions and genotype 13, 14 and 17 produced higher yields under drought stress conditions. In this study, the effects of stress have reduced the function of genotypes. However, the decreasing values in different genotypes are different, so that sensitive genotypes were with the highest yield loss and endemic genotypes with the least functional deficiency faced.
    Keywords: Bi-plot, Cluster analysis, Correlation, Drought, yield
  • Bahamin Seyed Hayat Gheyb, Mani Mojaddam *, Nazli Derogar Pages 75-84
     
    Introduction
    Barley (Hordeum vulgare L.) is one of the oldest crops, and its cultivation dates back to 7,000 years BC. This plant is the least expected crop, whose range of adaptation and distribution is more than other crops. Barley is the fourth most important cereal in the world after wheat, rice and corn. The origin of the barley region is fertile. It has diploid and tetraploid species, but its cultivars are diploid. Water is a key factor in the production of crops. The yield of crops in many areas is limited by living or non-living environmental stresses, and therefore, there is a significant difference between actual yield and yield potential of crops. Low moisture content in each of the different stages of growth reduces water absorption, nutrients, decreases the transfer of elements within the plant, and ultimately reduces the yield of the grain or the final product. Optimal use of water is of great importance, especially in areas where dry climatic conditions and Semi-dry is dominant.
    Materials and methods
    In order to evaluate the effect of effect of zinc sulfate on quantitative and qualitative characteristics of barley in late season drought stress conditions, a field experiment was carried out to in Baghmalek province in 2016-17 in split plot based on randomized complete block design with four replications. Experimental treatments included three levels of Irrigation cut at flowering stage, Irrigation cut at grading stage and Full irrigation In main plots and Zinc sulfate fertilizerwas 34% in three levels (0 (control), 30 and 60 kg.ha-1) in sub plots.
    Results and discussion
    The results showed that drought stress in the end of the season had a significant effect on grain yield, number of seeds per spike, 1000 seed weight, protein content and protein yield. Also application of manganese Zinc sulfate fertilizer significantly affected yield components, grain yield and protein yield. The highest number of spikes per square meter was allocated to 60 kg / ha treatment with 381.61 and the lowest number of spikes per m2 for non-application of Zinc sulfate fertilizer treatment to 334.85. It seems that Zinc sulfate fertilizer in plants increases photosynthesis and photosynthesis, as well as increasing the amount of auxin hormone increases plant growth and spike production by the paws. Due to the lack of malnutrition, the number of spikes per square meter increases. The highest grain yield (389.6 g/m²) was obtained from 60 kg.ha-1 Zinc sulfate fertilizer and the lowest (2336.3 g/m2). The highest grain yield in irrigation treatments (with a mean of 381.3 g / m2) and the lowest grain yield (with a mean 252.52 g / m2) were allocated to irrigation cut off at flowering stage. Studies have shown that moisture restriction at flowering time reduces the transfer of photosynthetic materials and, consequently, wrinkles the grain. In contrast, moisture availability in the flowering stage increases the grain filling period, resulting in more photosynthetic materials for seeds, which increases seed yield. Interaction between end season drought stress and Sulphate fertilizer had a significant effect on grain yield. The highest grain yield was allocated to full irrigation treatment and 60 kg.ha-1 Zn sulfate fertilizer treatments.
    Conclusion
    In general, it can be stated that the soils of many southern regions of the country are limestone with high pH and low organic matter and zinc deficiency is very probable. In this research, it was determined that fertilizer use plays an important role in the growth of oat plants, and also considering that the highest grain and protein yields as a quantitative and qualitative function of using Zn sulfate fertilizer, which is one of the low-level elements. To be achieved. It can be concluded that by using such fertilizers, the best conditions can be obtained to achieve the maximum quantitative and qualitative yield of the barley plant. Therefore, in terms of implementation of this research, 60 kg / ha Zn sulfate fertilizer application and irrigation had the most significant effect on the studied traits.
    Keywords: End of season drought stress, Qualitative, quantitative yield, Yield components, Zinc sulfate
  • Sara Daylami, Mani Mojaddam* Pages 85-94
     
    Background and Objectives
    The cowpea (vigna unguiculata L.) including grains, grown in tropical and sub-tropical countries, especially in the countries of Asia, Africa and South America, and it is considered an important source of nutrition. Among legums, in terms of cultivars and economic value, the first place belongs to beans. Good climate (warm to moderate summer) and adequate water in the areas under beans, high quality soils and high depth of clay are the main reasons for increasing its cultivation area. Water is a key factor in the production of crops. The yield of crops in many areas is limited by living or non-living environmental stresses, and therefore, there is a significant difference between actual yield and yield potential of crops. Low moisture content in each of the different stages of growth reduces water absorption, nutrients, decreases the transfer of elements within the plant, and ultimately reduces the yield of the grain or the final product. Optimal use of water is of great importance, especially in areas where dry climatic conditions and Semi-dry is dominant. Therefore, the present study aimed to investigate the effects of humic acid spraying on the quantitative and qualitative characteristics of bean-eyed beans under irrigation regimes in Hamidieh region.
    Materials and methods
    This research was carried out in 2016 in a farm located in Hamidieh with a longitude of 48 degrees and 10 minutes east and 31 degrees and 33 degrees north latitude and 13 meters above sea level. This study was carried out as split split plot in a randomized complete block design with three replications. Treatments included irrigation regimes at three levels (60, 90 and 120) mm evaporation from class A evaporation pan in the main plots and different times of humic acid spraying at three levels (no spraying, spraying at vegetative stage, Spraying at flowering stage) in sub plots.
    Results
    The results showed that irrigation regimes had a significant effect on grain yield, number of pods per plant, number of seeds per pod and protein yield. The highest grain yield (205.42 g/m2) was obtained from 60 mm evaporation from the evaporation pan and the lowest with an average of 160.2 g/m2, with 120 mm evaporation from evaporation pan. Also, the application of humic acid spraying dates significantly affected seed yield and protein function. Humic acid increases the amount of nutrients (seed storage compositions) by increasing the activity of the rosicose enzymes and increasing the photosynthesis activity of the plant, possibly by improving the production of sugar, protein and vitamin in the plant, and the positive effect on the various aspects of photosynthesis.The highest grain yield (200.77 g/m2) was obtained from spray application during vegetative time and the lowest (152.52 g/m2) was obtained from non-spray application. The interaction of irrigation regimes and spraying periods of humic acid had a significant effect on grain yield. The highest grain yield was assigned to 60 mm evaporation from evaporation pan and humic acid spraying treatment at a vegetative stage of 213.88 g/m2.
    Conclusion
    Therefore, it can be concluded that the use of humic acid due to different physiological effects, in addition to increasing yield, can play a positive role in decreasing the use of chemical fertilizers as well as environmental pollution. Therefore, as a natural source material, To sustain and increase the production of crops. Drought stress increased protein percentage, but irrigation at flowering and podding stage reduced the protein percentage. Despite the high percentage of protein in 120 mm evaporation from the pan, the protein function in this treatment was less than the other two treatments due to low grain yield. Therefore, in order to achieve maximum grain yield, 60-millimeter water irrigation with evapotranspiration from the pan is recommended by application of humic acid spraying at the vegetative stage.
    Keywords: Grain yield, Number of seeds per pod, Protein yield
  • Ghader Rostami, Mohammad Moghaddam *, Elham Saeedi Pooya, Ladan Ajdanian Pages 95-110
     
    Introduction
    Spearmint is one of the plants that attracted the attention of researchers because of its economic and pharmaceutical importance. This plant is one of the most important and most famous species of mint which disperses in different parts of the world. One of the scarce resources that is affected by rainfall is water. The effect of water stress depends on the duration, durability and amount of deficiency. One of the most important factors limiting the growth of plants around the world is drought, which is the most common environmental stress. One of the most effective mechanisms that is used by plant in water stress condition is osmotic regulation. The accumulation of proline and soluble sugars (as the most important osmolite) in regulation of osmotic is done to dominate the negative effects of drought stress. Results of researches have shown that drought stress has effective effect on the growth and biochemical characteristic of plants, and it differs among different plants. Optimum plant nutrition is one of the effective methods for plant resistance in drought conditions. Humic acid is one of the most important fertilizers in the agriculture. It creates more space for water penetration by modifying physical soil characteristic and improving soil granulations. Humic acid increases the activity of photosynthesis by increasing the activity of the Robisco enzyme. To consider the high importance of spearmint as a valuable vegetable and medicinal plant, the aim of this study was to estimate the resistance of spearmint to different levels of drought stress and evaluate the effects of foliar application humic acid as a moderator factor in drought stress condition.
    Materials and methods
    A pot research was conducted in factorial experiment in a completely randomized design with 3 replications to investigate the effects of humic acid as a growth factor and moderator of the effect of drought stress, on Mentha spicata L. at the Faculty of Agriculture, Ferdowsi University of Mashhad. The first factor was three levels of drought stress (30, 70 and 100 % FC) and the second factor was four levels of humic acid (0, 100, 500 and 1000 mgL-1). At the firstly, spearmint rhizomes with 10 cm length were prepared with at least 2 buds. In the middle of March, about 4 rhizomes were cultivated in depth of 5 cm of pots soil. Foliar application of humic was used at three stages (one week before drought stress and one and three weeks after applying drought stress) on the plant surface. We didn’t use any humic acid on the control treatment. About 4 weeks after humic acid application, the morphological, physiological and biochemical traits were measured at flowering stage.
    Results
    Vegetative traits such as plant height, number of branches, leaf length, leaf width and fresh and dry weight of leaf and stem showed a significant decrease with increasing drought stress (70% of field capacity) in compared to control treatment. Foliar application of humic acid, especially 1000 mgL-1 improved these traits in compared to control plants in drought stress condition. Also, the mean comparison of the interaction treatments showed that the highest amounts of photosynthetic pigments was observed at 70% FC and application of 1000 mgL-1 of humic acid and the least one was belonged to control treatment and application of 500 mgL-1 of humic acid. The highest antioxidant activity of leaf extract (80.66%) and total phenol (0.87 mg/g fresh weight) were observed in plants treated with 1000 mgL-1 humic acid and 70% FC. The highest relative water leaf content was obtained at non-stress conditions (control) and the foliar application of 1000 mgL-1 of humic acid.
    Conclusion
    This study showed that spearmint is very susceptible to drought stress, which could not withstand drought stress of 30% FC even for a short time. In general, means comparison of results showed that drought stress significantly reduced the morphological traits of spearmint. Also, the interaction treatments showed that the using of 1000 mgL-1 humic acid had the greatest effect on the growth indices. The highest amounts of photosynthetic pigments was observed at 70% FC and foliar application of 1000 mgL-1 of humic acid and the lowest one was belonged to control treatment of humic acid and without stress condition. Also, the highest levels of total phenol and antioxidant activity were observed in 70% FC and 1000 mgL-1 humic acid treatment. Therefore it can be stated that spearmint is high susceptible plant to drought stress because of sever effects of drought stress on its growth characteristics and physiological processes. The foliar application of humic acid, especially at high concentration (1000 mgL-1) can be effective in regulating the osmotic potential under slightly drought stress conditions. So, it can be used as an organic fertilizer in sustainable agriculture.
    Keywords: chlorophyll, Organic materials, Proline, Relative water content
  • Hamdollah Eskandari *, Kamyar Kazemi Pages 111-122
     
    Introduction
    Undr the condition of simoultaniousley irrigation of some crops, there is a shortage of water for irrigation. In this conditions, scheduling of the irrigation is crucial. In irrigation programs, evaporation pan is widley used. There are some reports for the effet of deficit irrigation on grain yield of sesame, where drought stress reduced growth and grain yield of sesame from 1212 to 624 kg ha-1 (Mehrabi and Ehsanzadeh, 2012). Application of fertilizers with ecological source, including animal manure and compost, can be used instead of chemical fertilizers, where application of such fertilizers can supply nutrients for crops, increase soil fertility and also maintain organic matter of the soil. Since the effect of fertilizer on the grain yield of sesame under different irrigation conditions is not well documented, the current research was aimed to determine the response of sesame to the source of nutrient under drought stress conditions.
    Materials and Methods
    A field experiment was conducted in Shadegan, Khuzestan province, during 2016-17 growing season to evaluate the effect of chemical and organic fertilizers on yield and yield components of seasame under different irrigation conditions. The experiment was conducted as a split plot based on RCBD with three replication where irrigation levels (irrigation after 100, 200 and 300 mm evaporation from evaporation pan) were assigned as main plot and fertilizer type (control, chemical fertilizer including 250 and 100 kg ha-1 phosphorous and nitrogen fertilizers, respectively, 30 t ha-1 animal manure and 30 t ha-1 compost) were allocated to sub plots. All compost, animal manure and ammonium phosphate and half of nitrogen fertilizer were applied before planting. At harvest time, plant height, leaf number per plant, branch per plant, capsule per plant, grain per capsule, 1000-grain weight and grain yield were measure. Harvest index and oil percentage were also determined.
    Results and discusions

    The highest plant highet was achieved in 100 mm evaporation from evaporation pan which was not significantly difference with the irrigation interval of 200 mm mm evaporation from evaporation pan. The lowest plant height was recorded in control treatment which was 25, 20 and 10 percent lower than that of chemical fertilizer, animal manure and composr, respectively. the most leaf number was recorded in 100 mm evaporation from evaporation pan. Application of chemical fertilizer produced the highest leaf number. Irrigation interval of 100 mm evaporation from evaporation pan had the highest branch per plant.
    Sesame had the highest capsule per plant and 1000-grain weight in 100 mm evaporation from evaporation pan which was not significantly difference with 200 mm evaporation from evaporation pan. Application of chemical and animal fertilizers produced highest capsule per plant. However, compost had no significant effect on this trait. Irrigation after 300 mm evaporation from evaporation pan resulted in te highest harvest index.
    The lowest oil percentage (47.5%) of sesame was achieved in 300 mm evaporation from evaporation pan and no application of fertilizer. The highest oil yield of sesame was recorded in 100 mm evaporation from evaporation pan which was 17% and 43% more than that of 200 and 300 mm evaporation from evaporation pan. Application of animal manure and compost resulted in 35.5% and 16% increase of oil yield.
    Keywords: Animal manure, Compost, Drought stress, Grain yield, Harvest index
  • Sadegh Bahamin, Alireza Koocheki *, Mahdi Nassiri Mahallati, Seyed Alireza Beheshti Pages 123-139
     
    Introduction
    The reduction of nutrients in agricultural soils is led to the intensive use of fertilizers because of low nutrients use efficiency of production systems (Taheri Oshtrinani and Fathi, 2016). An optimal level of nitrogen in the soil is requried to ensure vegetative growth, greater leaf area and proper yield with the minimum environmental consequences (Zabet et al. 2014; Bahamin, 2011). In this research chemical and biological sources of nutrients are compared for yield formation in water-stressed maize.
    Materials and Methods
    This research was carried out to investigate the effect of nitrogen and phosphorous fertilizers on yield quantity and quality of corn under drought stress. For this purpose, a split plot experiment with 4 replications was conducted in a randomized complete block design in 2015 at the Agricultural Research Station of Mehran (33° 07' North and 46° 10' East), southwest of Ilam province. The main plot factor included 3 irrigation regims of: irrigation up to 100% field capacity (no stress control), irrigation up to 75% of field apacity (moderate drought stress) and irrigation up to 50% field capacity (severe drought stress) and factorail combination of 3 levels of nitrogen and phosphorous fertilizers (including unfertilized control) was assigned to subplots. Recommended level of nitrogen was applied in the form of chemical fertilizer (in three stages before planting, stemming and flowering), or Azotobacter (seed inoculation) and the recommended rate of phosphorus was applied either in chemical form (triple superphosphate) or biological (seed-inoculated Pseudomonas fluorescens).
    Results and Discussion
    The effect of drought stress, nitrogen fertilizer, phosphorus fertilizer and interaction of all treatments on grain yield was significant. The highest grain yield of 12372 kg/ha was obtained with full irrigation when nitrogen and phosphorous were applied in chemical form. However, the same level of corn yield was achieved with biological nitrogen+chemical phosphorpus or chemical nitrogen+biological phosphorous. At all levels of drought stress application of triple super phosphate+azotobacter resulted to a significanty higher yield compared to unfertilized control. Based on the results under the severe drought stress (50% of field capacity) grain yield of 8093.6 kg/ha was obtained with azotobacter and triple superphosphate. The effect of drought stress, nitrogen fertilizer, phosphorus fertilizer and interaction of all factors on protein yield of corn was significant. The highest protein yield of 1105 kg//ha was achieved in full irrigation when triple supplemented was combined with azotobacter. At all levels of water stress application of triple superphosphate together with azotobacter was led to a significnatly higher protein yield compared to control so that under severe drougth stress with triple superphosphate+azotobacter the protein yield was 639.4 kg/ha. However, under moderate water stress (75% of field capacity) protein yield was 774.4 kg/ha with Pseudomonas+Azotobacter wich was significanty higher that other combination of fertilizers under moderate stress. In severe stress treatment (50% of field capacity) chlorophyll a was 15.1 mg/g of leaf fresh weight, which was 13.7% higher than full irrigation treatment. The highest amount of chlorophyll b (4.92 mg/g of leaf fresh weight) was obtained when Azotobacter was applied together with super phosphate. Regardless to the source of phosphorus fertilizer the amount of chlorophyll b was highest with Azetobacter. Protein content was also maximum (9.32%) in Azotobacter+super phosphate combination.
    Conclusion
    Overall, the results of this study showed that Pseudomonas and Azotobacter in low and severe water stress conditions increased the quantitative and qualitative yield of corn. Furthermore, it can be concluded that biofertilizer Pseudomonas and Azotobacter can supply most of the nutrient requirements of maize particularly when water is limited.
    Keywords: Azotobacter, Inoculation, Protein, Pseudomonas, yield
  • mohammad ghasem jami, Amir Ghalavand, S. Ali Mohammad Modarres, Sanavy *, Ali Makhtassi, Bidgoli, Abolfazl Baghbani Arani, Amin Namdari Pages 141-152
     
    Introduction
    The sunflower (Helianthus annuus L.) is one of the most important oil-producing plants in the
    world. Innovative strategies are needed to improve water and nutrient use efficiencies for sustainable production in sandy soils. In recent years, there has been an increasing demand for agricultural products with specific qualities. Oil seeds are the most important sources of energy for human demand following cereals. During recent decades, Cultivation area of sunflower as a main oilseed crop considerably increased due to its short growth season, high oil yield and also its nutritional value. Unsaturated fatty acids such as Oleic, Linoleic acids include about 90% of sunflower oil. Evaluation of different nutrient sources to achieve more drought tolerance in sunflower is vital to achieve high quantity and quality yield. Oil quality and yield are both dependent upon the genotype of a plant and its interaction with the environment. Among the factors responsible for increasing crop yield and quality, irrigation and fertilizer are the most important.
    Materials and methods
    In order to evaluate the response of sunflower quantitative and qualitative yield to various nitrogen sources and zeolite under different irrigation regimes, a two-year study was carried out as split-factorial based on RCBD at Agricultural Research Faculty of Tarbiat Modares University in 2015 and 2016. Irrigation regimes including (irrigation after depleting 40, 60, 80% of available soil water (ASW), was considered as main plot while the combinations of the nitrogen sources (providing 100% of required N through manure farmyard, 50% farm yard+ 50% urea, 100% of required N through urea) and zeolite (0, 5 10 t ha-1) were regarded as subplot.
    Results and discussion
    The results showed the highest stem diameter and height in the first (respectively 2/2 mm and 186.7 cm) and second (respectively 2.26 mm and 168.3 cm) years were achieved by using zeolite and irrigation after depleting 40% of ASW. In addition, the highest grain oil and protein yield in second year were obtained by irrigation after depleting 40% of ASW accompanied with using zeolite. Water stress caused significant decline in unsaturated fatty acids including oleic, linoleic, stearic acids (respectively 22 and 7, 50 % in the first and 27, 6.8 and 52 % in the second year) while palmetic acid increased under water stress by 54.6 and 65.3% in the first and second years. Farmyard manure positively affected oil quality in sequential years through higher accumulation of oleic (by 9.2 and 9.7%), linoleic acids (by 7.8 and 8.2%) under water stress conditions.
    Conclusions
    The result showed that under well irrigated conditions using manure farmyard and under water stress manure farmyard accompanied with zeolite, led to the best results in terms of quantitative and qualitative yield. In general, zeolite application and farmyard manure could alleviate water stress adverse effects, and improved plant growth, yield and oil and protein concentration. Overall, using manure farmyard plus zeolite might be considered as agronomic approach to decrease chemical fertilizer application rates and improve the sustainability of agricultural systems especially when the sunflower plants were subjected to water shortage conditions.
    Keywords: Oil, Organic fertilizer, Protein, Unsaturated fatty acids, Water deficit stress
  • Hassan Ghasemian Ardestani*, Mohsen Jahan, Amir Hossein Shirani Rad Pages 153-163
     
    Introduction
    Drought stress is the main factor which limits crops production across the world. Selection of crops that are adapted to the climate of each region, the selection of suitable and resistant to environmental stresses, and the use of high-yielding farming practices play an important role in increasing the efficiency of rare source of irrigation water. Morphological and physiological recognition of drought resistance is important for the improvement of problems caused by drought conditions.
    Materials and methods
    In order to evaluate the yield and the yield components of selected canola varieties under different temperature and humidity regimes, a factorial split plot experiment was conducted based on randomized complete block design with three replications for two years (2015-2016) in Karaj region. The study site was a field of the Seed and Plant Improvement Institute, Karaj, Iran (35° 59′ N, 50° 75′ E, at the altitude of 1313 m). The main plot factor was included the growing season in two levels (autumn and winter). Irrigation in three levels (normal irrigation or control, Interruption of irrigation from flowering stage and Interruption of irrigation from podding stage) and spring rapeseed cultivars included Jerry, Julius, Zafar, RGS 003, Hayola 4815 and Zabul 10 were assigned to sub plots. Some traits were studied including plant height, slique number and slique length, seed yield, biological yield, 1000seed weight, harvest index. Data were analyzed using the general linear model (GLM) procedure of the statistical analysis system, SAS. When analysis of variance showed significant treatment effects, Duncan’s multiple range tests was applied to compare the means at P < 0.05. According to analysis of variances, treatments and interaction between treatments had significant effect on studied traits at 5 or 1% statistically levels.
    Results and discussion
    According to means comparisons, The results showed that in autumn cultivation under control irrigation, the Julius and the Zabol 10 cultivars with dry matter yield of 5592 and 5536 kg/ha, and under interruption of irrigation from flowering stage condition, Julius cultivar with yield of 2511 kg/ha, and in the case of interruption of irrigation from the podding stage, Julius and Zabul 10 cultivars with yield of 4124 and 3959 kg/ha were superior cultivars. In winter cultivation under normal irrigation conditions, the Julius and the Hyola 4815 cultivars with dry matter yield of 3551 and 3307 kg/ha, and the Hyola 4815 and the Zabol 10 cultivars in interruption of irrigation from the flowering stage with dry matter yield of 1595 and 1542 kg ha-1 and in interruption of irrigation from podding stage with 2308 and 2173 kg ha-1 had the highest dry matter yield.
    Conclusion
    Generally, Application of drought stress and winter planting date led to the reduction of yield in all varieties, the results of two years experiment showed that Jolius and Hyolla 4815 cultivars had the highest grain yield under different irrigation conditions. Hyola 4815 cultivar was also suitable for drought stress (interruption of irrigation in both stages). Therefore, these cultivars can be introduced as suitable cultivars in regions may be faced with drought and non-drought stress during the growth period.
    Keywords: Biological yield, Drought stress, Planting date
  • Hossein Shirazi *, Abbas Biabani, Hossein Saboori, Masomeh Naemi Pages 165-179
     
    Introduction
    Rice is the main source of calories in more than one-third of the world's population, increasing by 30 to 35 percent by 2050, according to demand, Iran supplies 50 percent of imports of rice, the import figure in 1993 was about 185 million tons worth one billion and four hundred and ten million dollars (Jedari, 2017). Drought is the most important limiting factor in rice production in 40 million hectares of rice cultivated land in Asia (Ghiasi et al., 2014). Water stress during the vegetative stage reduces the buds; if the stress at the reproductive stage and grain filling causes a decrease in the number of seeds and weight (Rahman et al., 2002). Water stress in the vegetative stage affects the overall biomass reduction, which results from reduced photosynthetic rates and dry matter weights (Tahmasebi et al., 2008). Due to lack of water resources, low irrigation efficiency in rice field, the necessity of increasing water productivity and sensitivity of rice plant to drought stress. In this research, the effect of low irrigation management on morphological traits and yield of rice varieties, as well as determining the best level of irrigation for production Desirable performance in rice varieties has been evaluated.
    Materials and methods
    In order to investigate the effect of irrigation management on morphological traits and yield of rice cultivars, four separate experiments were carried out in a randomized complete block design in a research farm of GonbadKavus University in 1395. Four experiments were carried out separately in 5, 10 and 15 days irrigation and irrigation periods. The irrigation treatments were applied for 40 days after planting in the field at maximum tillering stage. The second factor also includes six rice cultivars (An Iranian cultivar Domsiah and three cultivar IR66424–1-2–1-5، IR70360–38–1-B-1, IR 55411-50 and the two lines are being introduced 87.110 and 87.5.103). Morphological traits included : 1- Main cluster length, 2- Plant weight, 3- Leaves number, 4- Plant Height As well as yield and yield components including number of tillers per plant, number of pods in the main cluster, number of filled seeds in the main cluster, Fertility percentage, full grain weight in main cluster, grain weight per plant, grain yield and harvest index As well as the number of days to be considered.
    Findings
    Analysis of variance showed that there is a significant difference between all experimental treatment levels. Exerting stress reduces grain yield. The mean comparison results in terms of flood waters showed a cultivar of 87.110, Minimum time to treat and grain yield, which had no significant difference in grain yield in comparison with native damsayah cultivar. In drought stress, 5 days the highest grain yield and the lowest number of days till the cultivar was 87.5.103 was observed. Grain yield in 10-day irrigation stress was significant in IR 55411-50 cultivar compared to other cultivars. Also, the results showed that the figure 87.5.103 was early childhood. In the irrigation round 15 days, while the figure is 87. 110 did not have the highest grain yield, However, there was no significant difference between Damsayeh variety, Also, the Cultivar 87.110 is the earliest and best cultivar in the region.
    Keywords: Harvest index, Irrigation interval, Growth period, Grain yield, Rice
  • Nadia Gharechaei, Farzad Paknejad *, Hosein Shirani Rad, Ghasem Tohidloo, Hamid Jabbari Pages 181-195
     
    Introduction
    Selection of crops that are adapted to the climate of each region, the selection of suitable and resistant to environmental stresses, and the use of high-yielding farming practices play an important role in increasing the efficiency of rare source of irrigation water. The aim of this study was to evaluate the reaction of rapeseed genotypes to end-stage drought stress in delayed planting conditions. Material and
    Methods
    This study was performed to evaluation of late season drought stress on agronomic traits of autumn canola genotypes in two temperature planting dates. Experimental design was done as split plot in RCBD design with 3 replications at two years in Karaj province, Iran. In this experiment, the planting date included timely (7th October) and late planting date (27th October) and irrigation including common irrigation and interruption from slique stage in main plots and five canola genotypes consisted of L1030, L1204, L1110, L1114 and one commercial (Okapi) cultivar. Analyses were performed by using the SAS software version 9 By doing bartlett test and after defining it insignificantly (Except 2 case), combined analysis of variance was done and In order to compare the means, Duncan's multiple range test was used at the 5% level. Studied traits included plant height, branch number, slique number, slique length, seed number/slique, 1000seed weight, biological yield, seed yield, harvest index, oil content and oil yield.
    Results and discussion
    Results showed that in both planting dates, interruption of irrigation led to the reduction of yield. All genotypes had higher grain yield with 7th October planting date than late planting date and the effect of interaction between planting date and genotype on all traits except harvest index was significant. The highest mean of traits was obtained on the fifth of October and the genotype L1204. The highest mean grain yield (5118 kg ha-1) was attributed to L1204 genotype in the planting date of October 7 and the lowest mean (2297 kg ha-1) was allocated to L1114 genotype on planting date of 27th October. Highest grain yield were obtained by L1204 at normal irrigation (4733 kg ha-1) and interruption of irrigation (3400 kg ha-1). The highest grain yield in delayed planting condition and stop irrigation after silique stage (2460 kg ha-1) was observed in L1204 genotype. Also, according to results, it was founded that all treatments had significant effects on oil content and the highest oil percentage (44%) was obtained by L1204 genotype. Interaction effect of evaluated genotypes with planting date showed that all genotypes had higher mean at 7th October planting date, and the highest mean oil percentage (44.18%) was observed by L1204 genotypes at 7th October planting date and The lowest mean (41. 39%) was allocated to the Okapi genotype at the late planting condition. The highest mean at 27th October planting date (41.83%) was belonged to L1204 genotype.
    Conclusion
    Application of drought stress and late planting date led to reduction of yield in all genotypes but these reductions were less by L1204 genotype in compared to other genotypes.
    Keywords: Irrigation cutoff, Grain yield, Planting date, Silique stage
  • Zahra Tahmasebi *, Hossein Mohammadi dehbalaee Pages 197-207
     
    Introduction
    Black beans are a variety of common beans (Phaseolus vulgaris) and belong to the legumes. Black beans contain a wide range of flavonoids, as well as some phenolic acids. The problems of production of this product, which reduces yields, are non-biological stresses, including drought. About 60% of the world's cultivateted bean is at risk of intermittent drought or at the end of the season. Several indices have been proposed to assess the response of genotypes under different environmental conditions and to determine their resistance and susceptibility, which helps to select drought tolerant genotypes. The aim of this study was to investigate the effect of drought stress on yield and yield components of black bean genotypes and to evaluate the response of these genotypes to drought stress by indices of drought tolerance.
    Materials and methods
    14 bean genotypes including 11 black bean genotypes and 3 other genotypes (which were control genotypes) were obtained from the Gene Bank of Agricultural and Natural Resources department in Karaj in two completely randomized block designs with 3 replications in two adjacent plots In the educational research farm of Ilam University in the city of Mehran was cultivated. In the first experiment, irrigation was carried out as normal and irrigation intervals based on 50 ml evaporation from the evaporation pan. In the second experiment, water stress was applied at flowering stage. At this stage, the irrigation interval was based on 100 ml evaporation from the pan. The measured traits included number of pods per plant, number of seeds per pod, plant height, grain yield and 100 grain weight. After data collection, analysis of variance and mean comparison by LSD method were performed for the studied traits. In addition, in order to determine resistant and stress resistant cultivars, various indices related to stress resistance including SSI (stress susceptibility index), STI (stress tolerance index), TOL (stress tolerance index), MP (average productivity index), GMP (Geometric Productivity Indicator) and Harm (Harmonic Average Index) were calculated. In order to determine the best index, the correlation of genotypes yield under stress condition (YS) and without stress (YP) with drought tolerance index was calculated.
    Results and discussion
    The results of combined analysis of the data showed that the effect of environment and genotypes on all traits was significant and the diversity between the studied genotypes was observed in terms of traits under normal and stress conditions. In terms of yield, 1140 and 1170 genotypes had the highest and lowest yields respectively. In general, all traits were changed due to stress and their mean values decreased under stress conditions. The percentage of grain yield under stress was estimated to be 24.26%. The most changes due to drought stress in genotypes related to yield, pod number and plant height. The most changes were due to drought stress in yield, pod number and plant height of black bean genotypes. Based on the Principal Component Analysis on the six indicators, YP and YS in the genotypes evaluated, it was found that the two main components justify 98.9% of the total variation. The first component expresses 68.6 percent of the total variation. The highest positive factor in the linear composition of the first component was YP, YS, MP, GMP, and STI. Based on the analysis of the main components on the six indicators, YP and YS in the genotypes evaluated, it was found that the two main components justify 98.9% of the total variation. The first component expresses 68.6 percent of the total variation. The highest positive factor in the linear composition of the first component was YP, YS, MP, GMP, and STI.
    Conclusions
    Based on the findings of this study, yield loss in drought stress conditions in black bean genotypes was mainly due to the reduction in the number of pods per plant. According to correlation of YS and drought tolerance indices, STI, GMP and MP were the best indices of drought tolerance under stress conditions. Therefore, based on these indices, among the genotypes of black beans, 1183 genotype as the most tolerant (with 8.07 g per plant) and genotypes 1187 and 1177 as the most sensitive genotype to drought stress (respectively, with yield 4. 17 and 5.22 g per plant) were selected. Also, control genotypes (256, Talash and Daneshkadeh) had higher yields (respectively 18.72, 13.56 and 14.21 g per plant respectively) and, for most of the indices, were more resistant than black bean genotypes. By using bi-plot of the Principal Component, genotype 1183 selected as the most tolerant drought stress.
    Keywords: Combined analysis, Drought tolerance indices, yield, Yield components
  • Mozhde Aghili Lake, Elias Soltani *, Iraj Alahdadi, Fatemeh Benakashani Pages 209-221
     
    Introduction
    oilseed rape has a wide range of adaptation and grows well in many regions under variable temperatures. However, the ability of the varieties varies in response to the favorable and unfavorable conditions. Temperature stresses (high or low temperatures) have harmful effects on crops. Generally, temperatures below 10 ° C can damage germination and emergence. Low temperatures can also have a negative effect on the post-emergence stages of crops. The high temperatures can also reduce the total dry matter produced, the number of pods under development, the number of seeds per pod, the weight of seeds, and, finally, the yield of the plant. Also, high temperatures affect the development and maturity of the seeds, resulting in a higher level of yield. Identifying high or low tolerant cultivars can help researchers improve the new cultivars and increase the flexibility of selecting the right cultivar for farmers. There are several methods for evaluating cultivars at low and high temperatures based on farm or laboratory surveys. Field surveys are difficult, unsustainable and seasonal. Because in field conditions, temperatures and humidity fluctuate a lot. Various studies have been done to evaluate the variation of germination in heat or cold stress in different plants such as lettuce, alfalfa, sorghum, cotton, sesame, etc. However, there is not much information on canola cultivars in Iran. The aims of this study was to determine the cardinal temperatures (2) evaluate the tolerance of different genotypes at high or low temperatures and (3) and to study the secondary dormancy potential in Iranian genotypes.
    Materials and methods
    In order to, germination tests were conducted in fixed temperatures incubators with 5, 10, 15, 20, 25 and 30 oC on 10 oilseed rape genotypes, in 4 replications with 50 seeds. Finally, cardinal temperatures were estimated using segmented (for germination rate) and beta (for germination percentage) functions. The tolerance of genotypes to high or low temperatures were determined using estimated cardinal temperatures. Also, an experiment was conducted to investigate the potential of different cultivars for induction of dormancy, in which seeds of 10 oilseed rape genotypes were subjected to drought stress conditions to determine the percentage of total induction due to drought for each genotype. The percentage of germinated seeds, the percentage of seeds with dormancy and dead seeds can be determined. Finally, the percentage of induction of the secondary dormancy was calculated for each genotype. Statistical analysis was performed using SAS software.
    Results and discussion
    Marshall and Squire (1996) showed that the minimum temperature (Tb) for oilseed rape germination was about 3 °C. Soltani et al. (2013) showed that the minimum temperature for oilseed rape germination was 2.7 °C and under dry conditions up to 6.7 °C at -0.8 MPa increased. Also, they showed that the average thermal time for germination (TT50) increased from 29.5 °C/day at 0 MPa to 57.9 °C/day at -0.8 MPa. Results indicated that mean of base (Tb), optimum (To) and ceiling (Tc) temperatures for germination percentage were 4.99, 18.23 and 34,20 oC and also mean of base (Tb), optimum (To) and ceiling (Tc) temperatures for germination rate were 6.18, 24.76 and 39.40 oC. The Heat and Cold tolerance indexes were also different in different cultivars. Okapi cultivar was the most tolerant in heat tolerance index (5.95) and in cold tolerance index (8.48). X-Power had the lowest tolerance to heat (4.78) and cold (6.50). The potential of secondary dormancy induction also was at the highest level in Okapi (about 40 %). It seems that there was connection between secondary dormancy induction and tolerance to temperature stresses which needs more studies.
    Keywords: Beta function, Cardinal temperatures, Segmented function, Temperature stress
  • Peyman Eynizadeh, Hamid Dehghani *, Mostafa Khodadadi Pages 223-237

    Introduction and goals
    Coriander (Coriandrum sativum L.) is an annual plant that drought stress can impact on its yield. Drought stress is one of the most common environmental stresses limit agricultural productivities. This stress effects on many metabolic pathways such as photosynthesis, water absorption and transfer, enzymes’ activity and organic material transfer and accumulation. It can also lead to the accumulation of secondary metabolites in the plant. In the case of some quantitative and qualitative traits, such as the yield and the amount of the essential oil, the selection can be done indirectly with the help of some statistical techniques. This research was conducted to investigation of interrelated traits with fruit yield and fruit essential oil content and also to suggest two multipurpose selection procedures for simultaneous improvement of several traits in all three irrigation regimes by the help of graphical analysis in coriander. Thereafter top landraces based on all attributes for selection and cultivation in the well irrigated, gradual drought stressed and severe drought stressed irrigation regimes were identified. Material and
    methods
    Three experiments were carried out based on randomized complete block design with three replications at the Research Farm of Tarbiat Modares University in 2015. In experiments, normal irrigation, severe stress, and gradual stress were applied and combined analysis of variance was performed for 16 physiological, morphological and phonological traits. Genotypic and phenotypic variances, genotypic and phenotypic variation coefficients, heritability in broad sense and genetic progress percentage were calculated. Genotypic and phenotypic correlations were calculated according to Holland, 2006 in combined analysis of variance. Factor analysis using the genotypic correlation matrix of traits and plotting ecotype × trait biplot based on the first two factors, which had the highest correlation with the studied traits, was performed by MATLAB software. Clustering of genotypes and traits based on average traits in three experiments and also based on replication means separately in each experiment using Ward method and Square Euclidean Distance were performed and the corresponding heatmap was plotted using metaboanalyst 3.0 software.
    Results and discussion
    Combined ANOVA showed relatively high variation for ecotypes in most traits. The genotype × environment interaction was significant in most of the traits at 1% probability level. The traits of days to 50% of fruit maturity, 1000 fruit weight, fruit yield and relative water content of the leaves had a relatively high environmental impact, and the indices related to the environment had fairly large difference with the ecotype indices. The effect of the environment on the fruit yield was so high that the genetic variance was estimated to be zero. Prematurity related traits had a relatively high genetic variance, and their genetic advance was relatively high. Therefore, selection may be effective to improve these traits under normal and stressed conditions. The highest percentage of genetic advance was observed for traits of leaf chlorophyll and base leaf number. Phonological traits, basal leaf number, plant height, plant dry weight, number of branches, number of umbels, number of fruits per plant, chlorophyll content and essential oil content had a high value of heritability and genetic advance. In factor analysis, the first two factors explained 51.13% and 23.71% of the total variation. The first factor showed existence high genotypic correlation between the most traits with each other, and on the other hand, the second factor showed the correlation between the relative water content of the leaves and the number of days to fruit maturity. According to the obtained biplot, the ecotypes with the highest genetic potential for most of the traits were identified, which were respectively ecotypes 4, 11, 15, 3 and 14. The ecotypes and traits were categorized into three groups according to the heatmap clustering. The observed differences between these two graphical representations in the ecotypic and traits grouping are due to the fact that the biplot is independent of the environmental effects and the genotype × environment interaction, while the heatmap is drawn based on the average of ecotypes in different moisture regimes.
    Conclusions
    Selection above mentioned ecotypes and obtain a superior population by them may be useful in simultaneously improving the important economic traits such as the amount of essential oil, basal leaf number and dry weight of biomass in both normal and stress conditions. Prematurity and relatively high value of harvest index in ecotype 9 make it suitable for the second cultivation in endangered areas of drought at the end of the season to produce fruit and essential oil. Ecotype No. 10 had the highest amount of essential oil and number of base leaves, but the lateness of this ecotype caused it to be severely drought sensitive and its average fruit yield reduced in different irrigation regimes. A great similarity was found between the results of the two graphical analysis methods and the traits were well grouped in a method that the combination of irrigation regimes and ecotypes was not considered.
    Keywords: Drought stress, Genotype by trait biplot, Gradual stress, Simultaneous selection, Sudden stress
  • Mehdi Karimi * Pages 239-249
     
    Introduction
    Salinity stress is known as a worldwide abiotic stress responsible for reduced crop production. It is estimated that annual losses of yield due to salt induced land degradation is US$ 27.3 billion globally (Qadir et al., 2014). Social and economic dimentions of salinity stress can be employment losses as well as environmental degradation (Butcher et al., 2016). In addition, it is well documented that application of chemical fertilizers usually improve plant performance under saline conditons but results in plant fertilizer requirement under salt affected soils are contrary. While there is little evidence of yield benefits due to application of fertilizers in salinized fields at rates beyond optimal in non-saline conditions, there is enough evidence indicating that soil salinity does not affect or decrease plant fertilizer needs (Hanson, 2006).
    A hypothesis that potassium (K) application can reduce the negative effects of salinity on plant performance has been proposed, but, contradictory results have been reported. These include a reduction in salinity damage to crops when high concentrations of K are present in growth media as well as no response to K fertilizer under salinity or even a negative effect of K addition on salt tolerance (Bar-Tal et al., 1991). These contradictory results can be attributed to the types of experiments (field, greenhouse or laboratory), composition of the saline substrate, studies conducted over the short term vs. the long term and many other differences in experimental conditions (Grattan and Grieve, 1999).
    Thus K fertilizer management may need to be modified under arid and semiarid conditions of Yazd peovince with wide range of irrigation water qualities. Accordingly, the objectives of this field study were to (a) elucidate the interactions between K nutrition and the salinity of irrigation water and their effects on wheat growth and (b) test the possibility of wheat improvement at saline conditions by applying higher levels of K fertilizer.
    Materials and methods
    A field experiment was conducted on wheat at Sadooq Salinity Research Station, Ashkezar, Yazd, Iran. The soil at the experimental site was calcareous with 30.92% total nutrient value, sandy loam texture, pH 8.06 and 0.22 % organic carbon. Mean annual temperatue is 18°C and precipitation is 70 mm. The treatments, four potassium sulphate application rates (0, 100, 200 and 300 kg ha-1) and three irrigation water qualities (1.88, 7.22 , 14.16 dS/m), arranged in a randomized block, split plot design with three repelications. Consisting 12 rows of wheat, each field plot was 3*5 m. All plots received common agricultural practices including tillage and fertilizer application. Rgarding typical recommendations and guidelines for this region and soil type (Balali et al., 2000: Moshiri et al., 2015), all fertilizers, except urea that applied in 4 splits, were soil-applied before plnating and included 100 kg ha-1 triple superphosphate, 40 kg ha-1 FeSO4, 40 kg ha-1 ZnSO4, 40 kg ha-1 MnSO4 and 20 kg ha-1 CuSO4. To model the relationship between plant properties and irrigation water salinity, the data were subjected to different regression models at the probability level of 0.01 and 0.05 with the help of the Sigmaplot software. The analysis of variance for different parameters was done following ANOVA technique. When F was significant at p ≤ 0.05 level, treatment means were separated using DMRT.
    Results and discussion
    The results showed that increasing irrigation water salinity to 7.22 dS/m did not significantly affect wheat graine yield. This is due to the non-significant effect of salinity on 1000 seed weight, harvesting index and non bearing spikelets in addition to the significant increase in spike length, bearing spikelets, bearing spikelet numbers, seed number per spikes and total spikelet numbers. At the same time, the results showed 50% decrease in wheat grain and straw yield due to the increase in the salinity of irrigation water from 1.88 to 14.16 dS/m. As application of K fertilizer did not affect wheat performance significantly, it was concluded that K application did not increase wheat tolerance to salinity stress under field conditions of our experiment.
    Conclusion
    Overall, it was concluded that K fertilizer was not necessary for wheat production (6 Mg ha-1 grain and 9 Mg ha-1 straw) under saline and non-saline calcareous soils of Yazd province with soil available K of 150 mg kg-1.
    Keywords: Calcareous soils, Irrigation Water, Yazd
  • Adel Modhej *, Azam Karbalaei Pages 251-262
     
    Introduction
    Wheat has been planted in saline conditions in many areas of central and southern Khuzestan, and high temperatures at early planting date may exacerbate the effects of salinity. Investigations show that not only different crop species but also genotypes of a species may have a different tolerance to salinity. Main constructs of tolerant wheat cultivars include the separation of sodium and chlorine in vacuole root and leaf cells. It has also been reported that tolerance cultivars, with osmotic stress in the root environment, have better seedling growth rates. The reason for the difference between the wheat cultivars studied in response to salinity was the ratio of sodium to potassium in the seedling of these cultivars. Seedling tolerant to salinity in wheat has a lower sodium content and higher potassium content than sensitive genotypes.
    Materials and Methods
    In order to investigate the effect of salinity and temperature on germination and seedling growth of three genotypes of bread and durum wheat, this experiment was carried out in the laboratory of Islamic Azad University, Khouzestan Research Branch, in 2011 in Petri Dish growing conditions. Factorial experiment was carried out using three temperature treatments (15/10, 25/20 and 35/30 ° C night/ day), wheat genotypes (two bread genotypes of Chamran and 20 Sarasary and Durum Line D85-17) and salinity (0, 2, 4, 8, and 12 ds/m). During the experiment, the germinated seed was considered to have a root length of at least two millimeters. One week after the treatments, from each petri dish, five seeds were selected to measure the traits. The traits of root length, stem and coleoptile, germination percentage, germination rate and sodium / potassium ratio were measured.

    Results and discussion
    The results showed that salinity increased germination percentage significantly in wheat genotypes. The maximum and minimum stem length was 25.25 and 35.30 ° C, respectively. With increasing temperature from 15.10 to 25.20 ° C, there was 43% increase in stem length. The increase in temperature from 25.20 ° C to 35.30 ° C reduced the stem length by about 52%. The percentage reduction in the root length of bread wheat cultivars, Chamran, as well as the durum line in 12 ds.m-1 compared to control distilled water were 41.5, 41.1 and 59.5%, respectively. Wheat genotypes at 25/25 ° C had the highest seedling growth. The highest and lowest germination percentages were observed at 15/15 and 35/30 ° C temperature treatments. Line 17-85D in comparison with bread genotypes was more sensitive to salinity and temperature. Increasing ambient temperature exacerbated the effect of salinity on germination and seedling growth. Increasing temperature increased the effect of salinity on plumule length, so that the reduction in plumule length under salinity of 12 dS/m and 15/35, 25/20 and 35/30° C temperature treatments, was 33.3, 50 and 84 percent respectively. Na+/K+ ratio was higher in wheat genotypes at high temperatures. Durum line D85-17 had a higher Na+/K+ and sensitivity to salinity compared to two bread genotypes.


    Conclusions
    According to the results, sodium and potassium ratio index was a suitable criterion for evaluating reaction of genotypes to salinity in temperature treatments. The Durum line was more susceptible to salinity and two bread genotypes were more tolerant to salinity due to less sodium accumulation and a higher sodium to potassium ratio. Meanwhile, genotypes such as Chamran, with more tolerance to the temperature, had less susceptibility to salinity. In general, it was recommended that in order to increase the accuracy of the research, the response of other wheat genotypes to salinity and temperature should be studied.
    Keywords: Potassium, Radicle, Salinity, Sodium
  • Maedeh Bohlouli, Maryam Dehestani, Ardakani *, Mostafa Shirmardi, Jamshid Razmjoo Pages 263-280
     
    Introduction
    Salinity is an important environmental tension limiting growth and productivity of plants worldwide. About 7% of the world’s total land area is affected by different degrees of salinity. Saline soil can be defined as soil having an electrical conductivity of the saturated paste extract (ECe) of 4 dSm−1 (4 dSm−1 ∼40mM NaCl) or more. The harmful effects of high salinity on plants can be observed in different levels such as the death of plants or necrosis of plant organs and/or decreases in productivity. Some tolerant plants develop mechanisms either to exclude salt from their cells or to tolerate its presence within cells. Major processes such as photosynthesis, protein synthesis, and energy and lipid metabolism are affected in plants during the beginning and development of salinity stress.
    Oenothera biennis L., an important medicinal plant, known as evening primrose. Organic fertilizers develop favorable physical, chemical and biological environment in the soil. They stimulate plant root growth, increase nutrient uptake and soil water-holding capacity, decreases evaporation from the soil and surface water runoff, facilitate drainage, regulate soil temperature and provide a rich substrate for soil microbes. This study was conducted to determine the effects of soil salinity and organic amendments on some growth characteristics, concentration of phosphorus, sodium and potassium and catalase enzyme activity in evening primrose plant (Oenothera biennis L.). Material and
    methods
    In a factorial experiment and completely randomized design (CRD), six levels of organic amendments (control (without soil amendments), 1.5 and 3 g.L-1 mycorrhizal fungi, 16 and 32 mg l-1 humic acid and 25% v/v madder residue plant) and three levels of soil salinity (4, 7 and 12 dS.m-1) with three replications per treatments were applied in Mahmoodabad research field of Esfahan municipality. In this experiment, media without organic amendment was considered as control.
    Results and discussion
    Results showed that increasing soil salinity levels progressively decreased the growth characteristics and nutrients concentration. Salinity causes growth reduction due to the low osmotic potential of the medium and by a specific ion effect as a secondary cause in several vegetable crops. The results of present study showed that the organic media can improve plant height. This can be due to increased media moisture storage and enhanced nutrient absorption. In EC = 4 dS.m-1 the highest plant height, root length and P concentration obtained in plants treated with 3 g/kg mycorrhizal fungi. Where in 7 and 12 dS.m-1 salt, organic matter showed the best effect on relative water conductivity, reducing time to flowering, increasing the P and K concentration, fresh and dry weigh of root and shoot, also ratio of dry weight to fresh weight. Mycorrhizal treatment in 7 dS.m-1 showed the highest root length. In 12 the most dry weighet of root, ratio of dry weight to fresh weight, the number of active leaves and K concentration in 16 mg/l humic acid and the most number of active leaves, chlorophyll and the lowest concentration of Na obtained in madder residue plant. Also madder residue plant reduced Na concentration in 7 and 12 dS.m-1 levels. In 12 dS.m-1 plants didn’t show reproductive phase, but adding soil amendments caused flowering induction. Excess soluble salts in the root zone restrict plant roots from withdrawing water from surrounding soil, effectively and causes drought for the plant. The loss of photosynthesis in salt stress condition resulted in the loss of dry weight production at the leaf level of evening primrose. Generally, all treatments in all salt levels caused increasing growth and yield of plant.
    Conclusion
    According to the results, it is cleared that in normal condition, evening primrose plant could tolerate salt stress until 7 dS.m-1 but by suitable media culture its threshold tolerate will be increased until 12 dS.m-1. Also it was revealed that all treatments could increase plant tolerate to salt stress and growth characteristics.
    Keywords: Humic acid, Madder, Potassium, Sodium, Mycorrhizal fungi
  • Reyhane Pordel, Mohammad Kafi *, Masoud Esfahani, Ahmad Nezami Pages 281-289
     
    Introduction
    Stevia rebaudiana Bertoni in an ancient perennial shrub of South America, produces diterpene glycosides that are low-calorie sweetener sand about 300 times sweeter than saccharose (Savita et al., 2004). Stevia extracts, besides having therapeutic properties, contain a high level of sweetening compounds, known as steviole glycosides, which are thought to possess antioxidant, antimicrobial and antifungal activity. Stevia cultivation and production, especially in Iran, would further help those who have to restrict carbohydrate intake in their diet; to enjoy the sweet taste with minimal calories. In Iran, the best area that has the most similarity of favorable climate condition for Stevia cultivation is the north of Iran. However, poor soil aeration associated with excessive moisture usually influences plant establishment and growth negatively in this part of Iran. Heavy textured soils in northern regions of Iran are more susceptible to waterlogging after heavy rain, and hypoxia is likely to limit Stevia growth. Thus waterlogging is considered as one of the important limiting factors for Stevia cultivation in such regions. On the other hand, Oxidation-reduction systems in the soil, which are generally stable as long as the soil is bathed in oxygen, become unstable when the oxygen supply is restricted. Nitrate is stable in well-aerated soils but become unstable when the oxygen supply of the soil is cut off. Nitrogen is subjected to loss through denitrification because of the ability of facultative anaerobes to substitute nitrate for oxygen. Advantage can be taken from the reducing conditions in waterlogged soils to increase the utilization of nitrogen fertilizer. The objectives of the present experiment were to investigate the effects of waterlogging stress and the alleviation of the waterlogged damage by the application of nitrogen fertilizer in Stevia. Material and
    methods
    A greenhouse pot experiment was conducted in University of Guilan, in 2013. The experimental design was factorial using completely randomized design layout with three replications. Treatments included four waterlogging levels; (0, -5, -10 cm from soil surface and normal irrigation as control), in periods of 2 and 4 days of waterlogging and two levels of nitrogen (6‰ and no nitrogen spraying as control) by foliar spraying from source of urea. Because the economic organ of Stevia is its leaves samples were taken before flowering stage.
    Results and discussion
    Results showed that measured shoot traits including leaf percentage, leaf area density, specific leaf weight, leaf dry weight, leaf area, plant height, number of lateral branch, number of leaves were significantly different among treatments. Nitrogen application improved plant height (14%) (Bakhshandeh et al., 2016) but deceased leaf area density (14%) compared with control. Interaction of waterlogging duration and nitrogen fertilizer significantly influenced leaf percentage, specific leaf weight and leaf dry weight. During water logging period increase from two to four days, nitrogen application improved leaf percentage by 4.5%, specific leaf weight by 11%, and leaf dry weight by 14%. In addition, interaction between water logging level and nitrogen application significantly influenced specific leaf weight, number of lateral branch and leaf dry weight. For specific leaf weight in -5 cm water logging level, nitrogen fertilizer application resulted in 12% increase compared with the same water logging level but without nitrogen fertilizer. Nitrogen application under -10 cm water logging level improved the number of lateral branches by 9% compared with complete water logging level without nitrogen application. Also for leaf dry weight, nitrogen application under -10 cm water logging effect resulted in 11% increase compared with no nitrogen application. Generally, the results of this experiment show that nitrogen application under water logging stress improved growth features of Stevia although water logging stress reduce growth characteristics of Stevia. Nitrogen application under the highest waterlogging level improved leaf dry weight by 10% compared with no nitrogen application treatment. Because economic part of Stevia is its leaves, it is likely that nitrogen application under water logging stress improve this trait (Rashid et al., 2013).
    Conclusion
    Results of this experiment showed that although level and duration of flooding stress caused a reduction in stevia leaf production but nitrogen application can ameliorate the negative effects of the stress on this trait. Since leaf dry weight is the economical yield of stevia, N application will improve yield if this plant under flooding stress
    Keywords: Leaf dry weight, Nitrogen levels, Stevia leaf, Specific leaf weight
  • basir Atarodi, Amir Fotovat *, Reza Khorassani, Payman Keshavarz Pages 291-305
     
    Introduction
    Agricultural soils in Iran, as in many other countries, are slightly to moderately contaminated by cadmium. According to some published reports, the average content of cadmium in some agricultural products and soils of Iran was found to be above the FAO/WHO guidelines. Abiotic stresses including cadmium stress can lead to overproduction of reactive oxygen species (ROS) causing progressive oxidative damage and ultimately cell death. In order to reduce cadmium-induced toxicity and alleviate some adverse effects of this metal on plants, a number of strategies including phytoremediation have been developed. Meanwhile, it was found that application of some elements such as calcium could diminish adverse effects of heavy metals in plants. In addition to calcium, selenium due to its potential in mitigation of cadmium toxicity has gained increased attention in recent decades. Selenium, as an antioxidant, plays an important role in the maintenance of human health, and on the other hand, many soils and, consequently, the crops produced in them suffer from the deficiency of this element. Although some studies have reported protective roles of selenium in plants subjected to cadmium stress, due to the limited reports on the effects of selenium on wheat exposed to cadmium stress particularly under Iranian soils conditions, the present study was conducted.
    Materials and methods
    In winter 2015, a pot experiment was carried out based on a completely randomized design in factorial arrangement with three replications for each treatment at research greenhouse of agriculture faculty of Ferdowsi university of Mashhad, Iran. The site is situated at 36°2′ North latitude, 59°4′ East longitude at an altitude of 999.2 m above mean sea level. The experiment included four levels of selenium (0, 0.5, 1, and 4 mg kg -1 soil, in the form of sodium selenite) and three levels of cadmium (0, 5, 15 mg kg -1 soil, in the form of cadmium nitrate). Soil weighing 6 kg was put into polyethylene pots, irrigated with distilled water to field capacity each three days and left over for 45 days to attain equilibrium. Eight seeds of wheat (Triticum aestivum L. cv. Falat) were sown per pot and thinned to four plants after the seedlings of wheat were well established. Sixty days after germination, newly expanded leaf samples from each pot were taken for determination of leaf pigments, proline and enzyme activity. Meanwhile, shoots from each pot were harvested from 1 cm above the soil and rinsed four times (twice with distilled water, once with 20 mM EDTA and again once with distilled water). The samples were wiped with paper and oven-dried at 50 °C for one week. Finally, dry weight of the shoots was measured.
    Results and discussion
    Cadmium stress, selenium application, and their interactions had a significant effect on photosynthetic pigments concentration, proline content, catalase activity and shoot dry weight. Results showed that as cadmium concentration in soil increased, chlorophyll a, b concentration, carotenoids content, catalase activity and shoot dry weight decreased. In contrast, the accumulation of proline in the plants was stimulated after the cadmium treatment, by 25 % in the presence of the highest cadmium level, as compared to the lowest cadmium level. Selenium application exerted its positive influence on some physiological parameters in plants exposed to cadmium stress. Chlorophyll b concentration and enzyme activity were higher in plants treated simultaneously with selenium and cadmium as compared with plants treated solely with cadmium. However, selenium did not show positive effect on chlorophyll a concentration, carotenoid content and shoot dry weight in plants grown under cadmium stress. Meanwhile, selenium at high concentration had no beneficial effect on wheat but also led to a significant decrease in photosynthetic pigments content, enzyme activity and shoot dry weight.
    Conclusions
    The results of the present study revealed that cadmium stress negatively affected physiological parameters of wheat and decreased photosynthetic pigments concentration, catalase activity and shoot dry weight. In contrast, selenium supplementation at low concentration could improve partially some physiological responses in wheat under cadmium stress.
    Keywords: Antagonist, Catalase, Heavy metals, Photosynthetic Pigments, Selenium
  • Zahra Ghorbanpoor, Amir Lakzian, Abolfazl Abbaspoor, Ahmad Gholamalizadeh* Pages 307-317
     
    Introduction
    The increase in population and the increase of scientific and technical knowledge and the development of industries without observing environmental issues and standards has contributed to the pollution and collapse of the soil biomass balance. Cadmium is a heavy metal, an inessential and toxic element for plants that it enter to the earth by different human activities. Phytoremediation is one of the more efficient proposal methods in pollution effacement. The advantage of Phytoremediation is adding organic, nutrient elements and oxygen to the soil that improve the quality and structure of the soil in purging places. Plants also, create a cover for the soil and their roots stabilize the soil and thus reduce the wind and water erosion. There are reports about potassium fertilizer with plants for absorption of cadmium and Phytoremediation preferment. The cadmium ion can formed by permanent complexes with chloride quickly. Chlorides are very fluid and can be an important factor in cadmium distribution of the soil in the specific conditions. The aim of this research is investigation the effect of using chloride and potassium sulfate fertilizer to absorption of cadmium and Phytoremediation preferment by canola plant.
    Materials and Methods
    This research performed into factorial and completely random design with 4 potassium levels (0, 100, 200 and 300 mg/gr K2O) from sources of potassium chloride and potassium sulfate, separately and 3 levels of cadmium (0, 15 and 30 mg/kg) from the source of cadmium nitrate in 3 replications at canola plant in glasshouse of center research.
    Results and Discussion
    As far the results of analysis of variance of effects of Cadmium and Potassium fertilizers and their interaction have significant effect on the amount of Cadmium of root and shoot, root dry weight and Potassium of root. Also, according to the results, the main effects of cadmium and potassium fertilizers have significant effect on dry weight and Potassium of shoot, whereas the effect of their interaction on dry weight and Potassium of shoot isn’t significant. In the treatment of 15 mg/kg, at 200 and 300 mg/gr levels of Chloride Potassium and 300 mg/gr level of Potassium sulfate into control, increase the content of Cadmium of the root but the content of Cadmium in shoot in 200 and 300 mg/gr levels of Chloride and Potassium sulfate into control increase significantly. The results of interactions in levels of Cadmium and Potassium fertilizers on dry weight of root show that highest amount of the dry weight of root exists in 0 Cadmium treatment (control) in 200 mg/gr level of Potassium sulfate and the lowest amount of dry weight of root has been observed in 30 mg/Kg Cadmium treatment on 300 mg/gr Potassium sulfate level. Highest and lowest amount of dry weight of shoot is related to the control treatment of Cadmium and 30 mg/Kg Cadmium treatment respectively. Also the result of Cadmium treatment shows that the Potassium of shoot decrease significantly with increasing of Cadmium and all levels shows the significant reduction. Highest and lowest amount of Potassium of shoot is related to the 0 level of Cadmium and 30 mg/Kg level of Cadmium respectively. Investigation of the levels of Potassium fertilizers show that adding Potassium fertilizer increase the absorption of the Potassium of shoot has been observed in 300 mg/gr level of Potassium sulfate.
    Conclusion
    In this research, there is significant difference between Potassium fertilizers (sulfate and chloride Potassium), whereas highest amount of the absorption of Cadmium has been observed in 300 mg/gr level in chloride Potassium, so according to the results of the glasshouse experiment, the efficiency of Phytoremediation improved however continuity of researches seem to be imperative in the farm conditions
    Keywords: Cadmium heavy metal, Canola plant, Phytoremediation, Potassium fertilizer
  • Omid Sadeghipour* Pages 319-329
     
    Introduction
    With increasing population and the intensification of industrial, urban and agricultural activities, the concentration of heavy metals in agricultural soils is also increasing. Lead (Pb) is one of the most toxic heavy metals that severely limit the crops growth and productivity. Exogenous application of some compatible solutes such as proline and glycine betaine is one of the effective methods for improving plants tolerance to abiotic stresses. Although much research has been done on the effect of proline and glycine betaine application on increasing the tolerance of different plants to abiotic stresses, including heavy metals, however, there is very limited information about the comparison of the application of these compatible solutes on improving common bean tolerance to Pb toxicity, therefore, the present experiment was designed and carried out.
    Materials and methods
    In order to comparison study the effect of proline and glycine betaine application on Pb stress tolerance of common bean plant, a pot experiment was done at the spring and summer of 2015 in south of Tehran. This research was conducted as a completely randomized design with 6 treatments and 4 replications. The treatments included the following levels: Control (no Pb, proline and glycine betaine); Pb stress (500 mg lead nitrate kg-1 soil); Pb stress + seed priming with 25 mM proline; Pb stress + seed priming with 50 mM proline; Pb stress + seed priming with 25 mM glycine betaine; and Pb stress + seed priming with 50 mM glycine betaine.
    Results and discussion
    The results of this study showed that Pb stress increased root Pb concentration and oxidative damage to common bean plants. Pb toxicity also reduced the chlorophyll value, relative water content (RWC), plant height, leaf area and root and shoot biomass. However, under Pb stress conditions, seed treatment with proline or glycine betaine reduced Pb uptake, increased activity of antioxidant enzymes and declined oxidative damage, which improved the chlorophyll value, RWC, plant height, leaf area and root and shoot biomass. There were no significant differences between proline and glycine betaine treatments.
    Conclusions
    According to the findings of this study, seed priming with proline or glycine betaine by reducing Pb uptake, increasing the activity of antioxidant enzymes, chlorophyll value, and plant water status, can be used as a beneficial method for improving tolerance of common bean to Pb stress.
    Keywords: Antioxidant enzymes, Chlorophyll value, Compatible solutes, Heavy metals