فهرست مطالب

بوم شناسی کشاورزی - سال دهم شماره 3 (پاییز 1397)
  • سال دهم شماره 3 (پاییز 1397)
  • تاریخ انتشار: 1397/09/06
  • تعداد عناوین: 21
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  • سرور خرم دل *، پرویز رضوانی مقدم، هما عزیزی، جواد شباهنگ، محمد سیدی صفحات 603-619
    این آزمایش با هدف ارزیابی نقش مدیریت تلفیقی کودهای آلی، شیمیایی و بیولوژیک بر خصوصیات رشد، عملکرد گل و بذر و اجزای عملکرد گیاه دارویی ختمی (Althea officinalis L.) ، به صورت فاکتوریل بر پایه طرح بلوک های کامل تصادفی با دو فاکتور انواع کود و تلقیح با باکتری تیوباسیلوس با سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد در سال زراعی 92-1391 به اجرا درآمد. فاکتور کود در چهار سطح شامل کود دامی (40 تن در هکتار) ، کمپوست (40 تن در هکتار) ، کود شیمیایی متداول NPK (114، 18 و 220 کیلوگرم در هکتار) و عدم کاربرد کود (شاهد) و فاکتور تلقیح با باکتری تیوباسیلوس همراه با مصرف گوگرد در چهار سطح شامل تلقیح با باکتری تیوباسیلوس، 200 کیلوگرم گوگرد در هکتار+ تلقیح با باکتری تیوباسیلوس، 200 کیلوگرم گوگرد و شاهد بودند. صفات مورد مطالعه شامل ارتفاع بوته، شاخص سطح برگ حداکثر، وزن خشک برگ، وزن خشک ساقه، وزن خشک کل، اجزای عملکرد شامل تعداد شاخه جانبی، تعداد کپسول، تعداد دانه و وزن هزار دانه و عملکرد گل، بذر و بیولوژیکی ختمی بودند. نتایج نشان داد که اثر کودهای آلی، شیمیایی و بیولوژیک بر ارتفاع بوته، شاخص سطح برگ حداکثر، وزن خشک برگ، وزن خشک ساقه، وزن خشک کل، اجزای عملکرد و عملکرد گل، بذر و بیولوژیکی ختمی معنی دار (01/0p≤) بود. بالاترین شاخص سطح برگ حداکثر در پایان فصل رشد برای تیمار تلفیقی کود شیمیایی و تیوباسیلوس+گوگرد با 3/12 و پایین ترین شاخص سطح برگ حداکثر برای شاهد با 3/1 به دست آمد. بالاترین عملکرد گل و بذر برای تیمار تلفیقی کود شیمیایی و تیوباسیلوس+ گوگرد به ترتیب برابر با 33/175 و 91/99 گرم بر متر مربع و کمترین میزان برای شاهد به ترتیب برابر با 33/32 و 31/9 گرم بر متر مربع به دست آمد. در شرایط کاربرد کودهای شیمیایی، دامی و کمپوست در سطوح جداگانه تیوباسیلوس و گوگرد و عدم کاربرد، عملکرد گل بیش از 100 درصد نسبت به شاهد بهبود یافت، در حالی که مصرف کودهای شیمیایی، دامی و کمپوست به همراه کاربرد تیوباسیلوس+گوگرد به ترتیب توانستند منجر به بهبود 106، 89 و 72 درصدی عملکرد گل در مقایسه با شاهد شوند. با توجه به بالا بودن اسیدیته خاک در اکثر خاک های زراعی ایران می توان مصرف تلفیقی گوگرد همراه با تلقیح با تیوباسیلوس را به عنوان راهکاری موثر برای بهبود جذب عناصر غذایی خاک مدنظر قرار داد.
    کلیدواژگان: اسیدیته خاک، تیوباسیلوس، حاصلخیزی خاک، کشاورزی پایدار
  • سیده سعیده زنده باد، پرویز رضوانی مقدم *، رضا قربانی، رضا خراسانی صفحات 621-634
    به منظور بررسی تاثیر کودهای آلی، شیمیایی و تلقیح میکوریزایی بر شاخص های رشدی، عملکرد کمی و کیفی چین های مختلف گیاه دارویی شوید (Anethum graveolens L.) ، آزمایشی در مزرعه تحقیقاتی دانشگاه فردوسی مشهد در سال زراعی 92-1391 به اجرا درآمد. آزمایش به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی اجرا شد. در این مطالعه 12 تیمار که شامل فاکتوریل کود آلی و شیمیایی در چهار سطح (کود دامی، ورمی کمپوست، کود شیمیایی اوره و شاهد) و تلقیح میکوریزایی در سه سطح (Glomus mosseae و Glomus intraradices و عدم تلقیح) در نظر گرفته شدند. بر اساس نتایج به دست آمده، بیشترین و کمترین عملکرد بخش سبزینه ای به ترتیب در چین دوم و چین سوم معادل 4259 و 2043 کیلوگرم در هکتار مشاهده شد. همچنین نتایج مقایسه میانگین ها نشان داد که شاخص سطح برگ، عملکرد بخش سبزینه ای، عملکرد ماده خشک، درصد و عملکرد اسانس، بین تیمارهای میکوریزایی با تیمار شاهد تفاوت معنی داری داشت. با این وجود بین تیمارهای تلقیح با G. mosseae وG. intraradices تفاوت معنی داری (در سطح پنج درصد) در صفات ذکر شده مشاهده نشد. عملکرد بخش سبزینه ای، عملکرد ماده خشک و عملکرد اسانس گیاه دارویی شوید در کودهای آلی (ورمی کمپوست و دامی) به طور معنی داری بیش از تیمار کود شیمیایی بود. با توجه به نتایج به دست آمده به نظر می رسد استفاده از انواع کودهای آلی در مقایسه با شیمیایی، نقش بیشتری در بهبود عملکرد کمی و کیفی گیاه شوید داشته باشد.
    کلیدواژگان: چین، عملکرد اسانس، ورمی کمپوست
  • علیرضا کوچکی *، مهدی نصیری محلاتی، عبدالله ملافیلابی، علی نوروزیان صفحات 635-646
    به منظور بررسی اثر دامنه وسیع وزن بنه بر رشد و گلدهی زعفران (Crocus sativus L.) ، آزمایشی در قالب طرح بلوک های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد در سال زراعی 91-1390 انجام شد. ده وزن بنه شامل کمتر از 2، 1-1/2، 10-1/6، 12-1/10، 14-1/12، 16-1/14، 18-1/16، 20-1/18، 24-1/20 و بیشتر از 24 گرم زعفران به عنوان تیمار مدنظر قرار گرفتند. فاکتورهای مورد مطالعه شامل تعداد و وزن تر گل، وزن تر و خشک کلاله، درصد بنه های فاقد گل در گروه های مختلف وزنی، بنه های یک، دو، سه و چهار گل و بیشتر، تعداد کل بنه تولیدی دختر، تعداد بنه های تولید شده دختری در گروه های وزنی کمتر از 4، 8-4، 12-8 و بیشتر از 12 گرم بودند. نتایج نشان داد که اثر دامنه وسیع وزن بنه بر تمامی صفات مورد مطالعه زعفران در سطح احتمال یک درصد معنی دار بود. بیشترین تعداد گل برای وزن بنه بیشتر از 24 گرم برابر با 000/300/1 گل در هکتار تولید شد. 34/99 درصد بنه های کمتر از 2 گرم فاقد گل آوری بودند. بنه های 16 گرم به بالا توان گل آوری نداشته و بنه های 1/20 تا 24 گرم و بیشتر از 24 گرم از بالاترین تعداد 3 و 4 گل و بیشتر برخوردار بودند. بیشترین عملکرد خشک کلاله نیز به همین تیمارها تعلق داشت که این برتری نسبت به تیمار وزن بنه 1/6 تا 10 گرم، 75 درصد افزایش داشت. کمترین و بیشترین تعداد بنه های دختری تولید شده به ترتیب مربوط به وزن کمتر از 2 گرم با 63000 بنه، بیشتر از 24 گرم به تعداد 000/550/25 بنه در هکتار بود و وزن های 16-1/14 گرم و کمتر از 2 گرم به ترتیب با 115 و 25 عدد بنه دختری کمتر از 4 گرم و وزن های بیشتر از 24 و 1/10 تا 12 گرم بیشترین و کمترین بنه های 8-4 گرم را به خود اختصاص دادند. بیشترین بنه های 8 تا 12 گرم و بیشتر از 12 گرم مربوط به وزن بنه بیشتر از 24 گرم و کمترین آن ها به وزن کمتر از 2 گرم و 1/2 تا 6 گرم اختصاص داشت.
    کلیدواژگان: بنه دختری، تعداد گل، وزن تر کلاله، وزن خشک کلاله
  • مهدی نصیری محلاتی *، علیرضا کوچکی صفحات 647-665
    به منظور نعیین شاخص تغذیه نیتروژن برای ارقام گندم (Triticum aestivum L.) آزمایشی مزرعه ای با آرایش فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار اجرا شد. دو فاکتور آزمایش عبارت بودند از سه رقم گندم (چمران، گاسکوژن و سایونز) و چهار سطح مصرف نیتروژن (صفر، 55، 110 و 170 کیلوگرم در هکتار). میزان ماده خشک و درصد نیتروژن قسمت های هوایی طی پنج نوبت در دوره رشد رویشی اندازه گیری شد. با استفاده از این داده ها غلظت های بحرانی و منحنی بحرانی رقیق شدن نیتروژن محاسبه و با منحنی رقیق شدن مرجع برای گندم مقایسه شد. منحنی حاصل از این تحقیق غلظت های بحرانی را کمتر از منحنی مرجع برآورد کرد، البته ضرایب معادله به ضرایب منحنی مرجع نزدیک و با آن قابل مقایسه بود. به طور کلی، منحنی رقیق شدن و جذب بحرانی نیتروژن کمبود، کفایت و بیش بود نیتروژن در قسمت های هوایی گندم را در سطوح مختلف مصرف این نهاده به خوبی توصیف کرد. در تیمارهای شاهد و kg N. ha-1 55 هر سه رقم گندم در شرایط محدودیت نیتروژن قرار داشتند. در حالی که در تیمار kg N. ha-1 170 مقدار نیتروژن تجمع یافته در گیاه بیشتر از نیاز رشدی بود، در تیمار kg N. ha-1 110 جذب نیتروژن در ارقام تحت بررسی به مقادیر بحرانی بسیار نزدیک بود. شاخص تغذیه نیتروژن (NNI) از نسبت غلظت اندازه گیری شده نیتروژن در قسمت هوایی به نسبت بحرانی آن محاسبه شد. در تیمارهای شاهد و kg N. ha-1 55 مقدار NNI در تمام دوره رویشی کمتر از یک بود در حالی که در تیمار kg N. ha-1 110 در حدود یک و در تیمار kg N. ha-1 170 بین 1 تا 3/1 قرار داشت. شاخص تغذیه نیتروژن در مرحله گلدهی رابطه معنی داری با عملکرد نسبی ارقام گندم داشت و حداکثر عملکرد هر سه رقم تحت بررسی در NNI بین 1-9/0 حاصل شد. بین پروتئین دانه و NNI در مرحله گلدهی نیز رابطه خطی معنی داری وجود داشت. بر اساس یافته های این تحقیق با استفاده از شاخص تغذیه نیتروژن که بر مبنای منحنی رقیق شدن این نهاده محاسبه می شود می توان برآورد دقیقی از سرعت رشد محصول، تولید ماده خشک، عملکرد و تا حدودی پروتئین دانه به دست آورد و مقدار بهینه کود نیتروژن را برای دستیابی به هر سطحی از عملکرد دانه تعیین نمود.
    کلیدواژگان: پروتئین دانه، جذب بحرانی نیتروژن، عملکرد دانه، غلظت بحرانی نیتروژن، منحنی رقیق شدن بحرانی نیتروژن
  • سرحد بهرامی، وریا ویسانی * صفحات 665-678
    کشت مخلوط با استفاده از عوامل زمان و مکان علاوه بر بهبود روش های تولید از جنبه زیست محیطی و سلامت انسان توان افزایش تولید محصولات کشاورزی را دارا می باشد. به منظور بررسی اثر تراکم بوته و نسبت های کشت مخلوط گیاهان علوفه ای یک ساله شامل: خلر، (Lathyrus sativus L.) ، نخود علوفه ای (Pisum avestum L.) ، ماشک گل خوشه ای(Vicia villosa L.) و ماشک مجاری (Vicia paninica L.) بر عملکرد کمی و کیفی جو (Hordeum vulgare L.) ، در قالب طرح پایه بلوک کامل تصادفی در سه تکرار در ایستگاه تحقیقاتی دیم کردستان در سال زراعی 93-1392 انجام گرفت. تیمارهای مورد بررسی ترکیبی از پنج سطح تراکم 100، 150، 200، 250، 300 بوته در مترمربع گیاهان علوفه ای و چهار نسبت بذور این گیاهان (0:100، 25:75، 50:50 و 100:0) در کشت مخلوط با جو بودند. نتایج نشان داد که بیشترین و کمترین مقادیر عملکرد علوفه تر و خشک به ترتیب از تیمارهای کشت خالص جو و کشت خالص گیاه علوفه ای با تراکم 100 بوته در مترمربع به دست آمد. نسبت های 75 درصد نخود علوفه ای+25 درصد جو در تراکم 250 بوته در مترمربع و 50 درصد ماشک گل خوشه ای+50 درصد جو در تراکم 300 بوته در مترمربع به ترتیب با 94/0 و 86/0 تن در هکتار بیشترین مقادیر پروتئین خام را دارا بودند. نسبت های کشت 75 درصد خلر+25 درصد جو در تراکم، 75 درصد نخود علوفه ای+25 درصد جو در تراکم، 50 درصد ماشک گل خوشه ای+50 درصد جو در تراکم و 50 درصد ماشک مجاری+50 درصد جو در تراکم به ترتیب با 19/1، 26/1، 16/1 و 13/1 نسبت برابری زمین نسبت به سایر نسبت های کشت برتری داشتند.
    کلیدواژگان: عملکرد، غلات، کیفیت علوفه، نسبت برابری زمین
  • محمد بهزاد امیری، ‍‍پرویز رضوانی مقدم *، محسن جهان صفحات 679-698
    به‎منظور بررسی اثر اسیدهای آلی، ریزوباکترهای محرک رشد گیاه و گونه‎های مختلف میکوریزا بر عملکرد و اجزای عملکرد گاوزبان ایرانی (Echium amoenum Fisch. & Mey.) پژوهشی در دانشگاه فردوسی مشهد در سه سال زراعی متوالی 91-1390، 92-1391 و 93-1392 به صورت اسپلیت‎پلات در زمان در قالب طرح بلوک های کامل تصادفی با سه تکرار انجام شد. هفت نوع اصلاح کننده خاک و کود بیولوژیک مختلف شامل 1- اسید هیومیک، 2- اسید فولویک، 3- نیتروکسین (حاوی باکتری های Azotobacter spp. و Azospirillum spp.) ، 4- بیوفسفر (حاوی باکتری های Bacillus sp. و Pseudomonas sp.) ، 5- بیوسولفور (حاوی باکتری Thiobacillus spp.) ، 6- میکوریزا (حاوی قارچ Glomus mosseae) و 7- میکوریزا (حاوی قارچ Glomus intraradices) و عدم استفاده از کود به عنوان تیمار شاهد در کرت های اصلی و زمان (سال های زراعی دوم و سوم) در کرت های فرعی قرار گرفتند. نتایج آزمایش نشان داد که بیشترین مقدار عملکرد گل خشک (1004 کیلوگرم در هکتار) در نتیجه کاربرد اسید هیومیک به دست آمد. کاربرد اسیدهای آلی هیومیک و فولویک وزن دانه در بوته را به‎ترتیب 38 و 25 درصد و تعداد دانه در بوته را به‎ترتیب 19 و 17 درصد نسبت به شاهد افزایش دادند. کودهای اسید فولویک، نیتروکسین، بیوفسفر، بیوسولفور، میکوریزا (Glomus mosseae) و میکوریزا (Glomus intraradices) نیز به ترتیب افزایش 27، 20، 4، 26، 30 و 28 درصدی عملکرد گل خشک را در مقایسه با شاهد سبب شدند. بیشترین شاخص برداشت گل و دانه به ترتیب در نتیجه استفاده از میکوریزا (Glomus intraradices) و اسید هیومیک حاصل شد.
    کلیدواژگان: اسید هیومیک، بیوسولفور، شاخص برداشت گل، میکوریزا، نیتروکسین
  • حمیدرضا توکلی کاخکی، مهدی نصیری محلاتی*، علیرضا کوچکی، علیرضا بهشتی صفحات 699-718
    نظام های رایج کشاورزی برای حفظ و تقویت حاصلخیزی خاک به کودهای شیمیایی به ویژه کودهای نیتروژنی وابسته می باشند. گرچه مصرف کودهای نیتروژنی نقش قابل توجهی در افزایش عملکرد داشته است، اما مصرف بی رویه آن با کاهش کارایی مصرف نیتروژن همراه بوده است. این پژوهش به منظور بررسی و تجزیه و تحلیل، روند تغییرات کارایی مصرف نیتروژن و تعیین سهم نسبی اجزای کارایی در نظام های زراعی گندم (Triticum aestivum L.) با استفاده از مدل CENTURY انجام شده است. نتایج به دست آمده در این مطالعه نشان داد که میانگین کارایی مصرف نیتروژن در نظام های زراعی گندم این مطالعه 3/28 کیلوگرم دانه به ازای هر کیلوگرم نیتروژن فراهم یا قابل جذب خاک بود. نظام های زراعی گندم (تبریز، شیراز، گرگان) بالاترین و در مقابل نظام های زراعی (کرمان، بیرجند، زابل) کمترین کارایی مصرف نیتروژن را دارا بودند. بررسی روند تغییرات عملکرد در مقابل کارایی مصرف نیتروژن نشان داد با افزایش یک واحدکارایی مصرف نیتروژن، عملکرد با شیبی معادل14/0 تن افزایش یافته است. از طرفی همبستگی مثبت و معنی داری بین کارایی مصرف نیتروژن با کارایی تبدیل (r=0. 73 p≤0. 01) و جذب نیتروژن (r=0. 69 p≤0. 01) به دست آمد. همچنین، تفکیک سهم نسبی اجزای کارایی مصرف نیتروژن حاکی از آن بود که در دامنه مصرف 120-80 کیلوگرم نیتروژن در هکتار سهم نسبی اجزای کارایی جذب و تبدیل به ترتیب 64 و 36 درصد بود که با افزایش مصرف نیتروژن به میزان 160-121 کیلوگرم در هکتار سهم نسبی کارایی جذب به 33 درصد وکارایی تبدیل به 67 درصد تغییر یافت. به نظر می رسد در نظام های تولید گندم هنگامی که جزء غالب کارایی جذب می باشد مدیریت زراعی و استفاده از روش های اصلاحی زمانی که جزء غالب کارایی تبدیل می باشد به عنوان رهیافت های پیشنهادی در جهت بهبود کارایی مصرف نیتروژن مورد توجه می باشند.
    کلیدواژگان: آنالیز اجزاء کارایی، کارایی تبدیل نیتروژن، کارایی جذب نیتروژن، همبستگی
  • وحیده صفی، احمد گلچین، سعید شفیعی * صفحات 719-732
    به منظور بررسی تآثیر اندازه و عمق جایگذاری بقایای گیاهی بر دینامیک کربن و نیتروژن آلی، آزمایشی به صورت کرت های دوبار خرد شده در سه تکرار و در قالب طرح بلوک های کامل تصادفی در مزرعه روی بقایای گندم (Triticum aestivum L.) به روش کیف کلش اجرا گردید. فاکتورهای مورد بررسی شامل مدت زمان خوابانیدن بقایای گیاهی در چهار سطح (1، 2، 3 و 4 ماه) ، عمق جایگذاری بقایای گیاهی در چهار سطح (5، 15، 30 و 45 سانتی متر) و اندازه بقایای گیاهی در سه سطح (2/0 تا 5/0، 1 تا 2 و 5 تا 10 سانتی متر) بودند که به ترتیب در کرت های اصلی، فرعی و فرعی- فرعی قرار داده شدند. پس از سپری شدن فواصل زمانی خوابانیدن، کیف های کلش از خاک خارج و پس از اندازه گیری وزن بقایای گیاهی باقی مانده در آن ها میزان کربن آلی نیتروژن کل بقایا اندازه گیری شد. نتایج نشان داد که بیشترین مقدار هدر رفت کربن و نیتروژن آلی چهار ماه پس از خوابانیدن، زمانی که بقایای گیاهی گندم با اندازه 2/0 تا 5/0 سانتی متری در عمق 30 سانتی متری خاک جایگذاری شدند اتفاق افتاد. در مقابل کمترین مقدار هدر رفت کربن و نیتروژن آلی یک ماه پس از خوابانیدن، زمانی که بقایای گیاهی گندم با اندازه 5 تا 10 سانتی متری در عمق پنج سانتی متری خاک جایگذاری شدند صورت پذیرفت. در این آزمایش 73/49 تا 07/54 درصد از کربن آلی و 48/34 تا 78/39 درصد از نیتروژن آلی بقایای گندم در یک دوره چهار ماهه وقتی بقایای گیاهی گندم به ترتیب در عمق 5 و 30 سانتی متری خاک جایگذاری شدند تلف گردید. از نتایج چنین استنباط می شود زمانی که کمبود رطوبت خاک عامل محدود کننده برای تجزیه بقایای گیاهی است، افزایش عمق جایگذاری بقایا با قرار دادن بقایا در لایه مرطوب خاک باعث افزایش سرعت معدنی شدن کربن و نیتروژن آلی می شود. همچنین خرد کردن بقایای گیاهی با افزایش سطح ویژه و سطح تماس بقایا با خاک، باعث افزایش سرعت تجزیه بقایا می شود.
    کلیدواژگان: بقایای گیاهی گندم، سرعت تجزیه بقایای گیاهی، مدت زمان خوابانیدن
  • بهروز سبحانی*، یوسف حسن زاده صفحات 733-746
    یکی از روش های برنامه ریزی کشاورزی تعیین و شناسایی نواحی مناسب برای کاشت گیاهان زراعی و باغی بر اساس شرایط آب و هوایی و فیزیوگرافی است. این امر، کشاورزان را قادر می سازد که خسارت ناشی از شرایط نامناسب اقلیمی بر محصول را در طول دوره رشد به حداقل برسانند. نخود (Cicer arietinum L.) یکی از محصولات زراعی در استان اردبیل است که حدود 5272 هکتار از اراضی استان زیر کشت این گیاه زراعی است. هدف از این تحقیق، شناسایی نواحی مناسب استان اردبیل برای کشت نخود در محیط GIS است. برای این منظور، ابتدا نیازهای مطلوب اقلیمی در طول دوره رشد نخود تعیین گردید، سپس داده های مورد مطالعه از قبیل، بارندگی، دما، ارتفاع، شیب، خاک و کاربری اراضی جمع آوری شدند. هرکدام از داده ها با استفاده از روش AHP تحلیل شدند و ضریب وزنی معیارهای اصلی، فرعی و زیر گزینه ها مشخص شدند. درنتیجه ضریب وزنی معیارهای اصلی از قبیل اقلیم با 603/0، توپوگرافی 245/0، خاک 114/0 و کاربری اراضی 038/ 0 تعیین گردید. در مرحله بعد، نقشه های موضوعی موردنیاز برای هریک از داده ها موردمطالعه در محیط GIS تهیه و برای هریک از پلیگون های نقشه، ضریب وزنی لحاظ شد و هریک از نقشه ها بر اساس روش AHP در محیط GIS طبقه بندی شدند. در نهایت با تلفیق نقشه ها، نقشه نهایی پهنه بندی کشت نخود در استان اردبیل در چهار کلاس تهیه گردید که حدود 18 درصد از مساحت استان خیلی مناسب، 45 درصد مناسب، 25 درصد متوسط و 12 درصد نامناسب برای کشت نخود است.
    کلیدواژگان: اقلیم کشاورزی، داده های جوی، عوامل فیزیوگرافی، تناسب اراضی، نیازهای مطلوب اقلیمی
  • امیر رضا صادقی بختوری*، بهمن پاسبان اسلام، نسترن حاجی زاده اصل صفحات 747-763
    به منظور بررسی اثر پرایمینگ و تنش کم آبی بر رشد و عملکرد آفتابگردان آجیلی (Helianthus annuus L.) آزمایشی در دانشگاه شهید مدنی آذربایجان به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار در تابستان 1393 اجرا شد. تیمارهای آزمایش شامل فاکتور پرایمینگ در چهار سطح (آب با نیتروکسین، آب با اکسین، آب مقطر (شاهد) و بدون پرایمینگ) و فاکتور تنش کم آبی در سه مرحله (ساقه رفتن، پر شدن دانه و شاهد (بدون تنش در کل دوره رشد) ) بودند. نتایج آزمایش نشان داد که تمامی صفات مورد بررسی تحت تاثیر اثرات اصلی پرایمینگ و تنش کم آبی قرار گرفتند. پیش تیمار کردن بذرها سبب افزایش معنی داری در سرعت رشد مطلق بوته و طبق، قطر طبق، تعداد دانه در طبق، وزن هزار دانه، عملکرد دانه و نسبت مغز دانه به کل دانه و کاهش درصد دانه های پوک در طبق شد. اما تنش کم آبی باعث کاهش تمامی صفات، به جز درصد دانه های پوک گردید. تنش کم آبی در مرحله پر شدن دانه باعث بیشترین کاهش عملکرد دانه در بوته در واحد سطح گردید. بیشترین مقدار عملکرد دانه در پرایمینگ آب با نیتروکسین به دست آمد. نتایج کلی این تحقیق، بیانگر این بود که پرایمینگ کردن بذور باعث کاهش اثرات سوء تنش کم آبی از طریق تحریک رشد و تقسیم سلولی و افزایش بنیه اولیه گیاهچه شده و همچنین می تواند در افزایش اجزای عملکرد و عملکرد آفتابگردان آجیلی عاملی موثر برای دستیابی به کشاورزی پایدار باشد.
    کلیدواژگان: پیش تیمار بذر، تنش رطوبتی، عملکرد دانه
  • علیرضا پیرزاد *، ناصر جعفرزاده، هاشم هادی، رامین ملکی صفحات 765-774
    کرچک (Ricinus communis L.) از مهم ترین گیاهان زراعی با ارزش است که در صنایع داروسازی، آرایشی و صنعت کاربرد فراوان دارد. به منظور بررسی اثرات تداخلی تاج خروس (Amaranthus retroflexus L.) بر عملکرد، درصد روغن و ترکیب اسیدهای چرب گیاه کرچک آزمایشی به صورت فاکتوریل در قالب طرح پایه بلوک های کامل تصادفی در سه تکرار در مرکز تحقیقات کشاورزی آذربایجان غربی (ارومیه) در سال 1392 اجرا شد. عامل اول شامل تراکم های 3، 4، 5 و 6 بوته در متر مربع کرچک و عامل دوم تراکم های صفر، 5 ، 10 و 15 بوته در متر مربع تاج خروس بود. نتایج نشان داد عملکرد روغن کرچک تحت تاثیر تراکم های کرچک، تاج خروس و اثر متقابل آن ها قرار گرفت، ولی ترکیب اسیدهای چرب روغن کرچک فقط تحت تاثیر معنی دار تراکم های تاج خروس بودند. با توجه به نتایج به دست آمده با افزایش تراکم تاج خروس کاهش 38-20 درصدی در عملکرد دانه، 39 درصدی در عملکرد روغن کرچک نسبت به کشت خالص (بدون علف هرز) مشاهده شد. با توجه به ویژگی های منحصر به فرد روغن کرچک که ناشی از ریسینولئیک اسید است با افزایش تراکم تاج خروس، این اسید چرب تا 19 درصد کاهش و پالمتیک اسید (74 درصد) و استئاریک اسید (108 درصد) ، لینولئیک اسید (12 درصد) و اولئیک اسید (64 درصد) در مقایسه با کشت خالص کرچک افزایش یافت. به طورکلی، نتایج نشان داد علف هرز تاج خروس وحشی در تراکم های 10 و 15 بوته در مترمربع علاوه بر کاهش عملکرد دانه و روغن با تغییر در ترکیب اسیدهای چرب باعث کاهش کیفی روغن کرچک نیز می شود.
    کلیدواژگان: اسید اولئیک، اسید پالمتیک، اسید ریسینولئیک، تداخل، عملکرد روغن
  • ژاله زارعی، حسن حیدری*، ایرج نصرتی، محمود خرمی وفا صفحات 775-787
    آفتابگردان (Helianthus annuus L.) از گیاهان زراعی است که به منظور تولید روغن یا آجیل زراعت می شود. به منظور ارزیابی امکان نشاءکاری آفتابگردان در شرایط آب و هوایی استان کرمانشاه این پژوهش در دو بخش گلخانه و مزرعه تحقیقاتی پردیس کشاورزی و منابع طبیعی دانشگاه رازی کرمانشاه در دو سال (94 – 1393) انجام شد. آزمایش در سال اول به صورت فاکتوریل و در قالب طرح بلوک های کامل تصادفی با چهار تکرار بود که فاکتورها شامل سه روش کاشت (کشت مستقیم بذر، کشت نشاء چهار هفته ای و کشت نشاء شش هفته ای) و دو تاریخ کاشت (کشت زود هنگام و کشت زمان معمول) بود. آزمایش در سال دوم به صورت طرح بلوک های کامل تصادفی با سه تکرار اجرا شد که تیمارها شامل نشاءکاری چهار هفته ای زودهنگام (تیمار برتر سال اول) و کشت مستقیم بذر (شاهد) بود. نتایج سال اول نشان داد که بیشترین ماده خشک تولید شده و بالاترین سطح برگ مربوط به نشاء چهار هفته ای زودهنگام بود که جهت تکرار آزمایش برای کشت در سال دوم انتخاب شد. نتایج پژوهش در سال دوم نشان داد که نشاءکاری در مقایسه با کشت مستقیم بذر به طور معنی دار باعث افزایش تعداد برگ، سطح برگ، ماده تازه و خشک بوته، ارتفاع بوته، تعداد دانه در طبق، وزن مغز و وزن پوست دانه، عملکرد دانه و وزن صد دانه شد.
    کلیدواژگان: اجزای عملکرد، روش کاشت، عملکرد دانه، کشت مستقیم بذر، ماده خشک
  • سحر افضلی هرسینی*، محمد صادق تقی زاده، علی بهپوری، فرزانه فرامرزی صفحات 789-803
    به منظور ارزیابی تاثیر کشت مخلوط ردیفی ارقام گندم (Triticum aestivum L.) بر تراکم، زیست توده و محتوای عناصر غذایی کم مصرف شاخساره علف های هرز و عملکرد محصول، یک آزمایش مزرعه ای در ایستگاه تحقیقاتی دانشکده کشاورزی و منابع طبیعی داراب، دانشگاه شیراز در سال زراعی 93-1392 انجام شد. آزمایش در قالب طرح بلوک های کامل تصادفی با هشت تیمار و سه تکرار اجرا شد. تیمارها شامل کشت مخلوط ردیفی ارقام گندم (: I1 کشت مخلوط شیرودی + لاین 11-91،: I2 کشت مخلوط شیرودی + لاین 15-91، I3: کشت مخلوط لاین 11-91 + لاین 15-91 و I4: کشت مخلوط شیرودی + لاین 11- 91 + لاین 15-91) وکشت خالص آن ها (S1: کشت خالص شیرودی، S2: کشت خالص لاین 11-91،: S3کشت خالص لاین 15-91 و S4: کشت خالص نسل ناخالص F2 به صورت توده بذری) بود. نتایج نشان دهنده تاثیر معنی دار مخلوط ژنوتیپ ها در کاهش تراکم، زیست توده و محتوای عناصر غذایی کم مصرف علف های هرز بود. بیشترین تراکم علف های هرز در کشت خالص شیرودی (33/39 بوته در متر مربع) و بیشترین زیست توده علف های هرز در کشت خالص لاین 11-91 (130 گرم در متر مربع) و کشت خالص شیرودی (3/121 گرم در متر مربع) مشاهده شد. بیشترین محتوای آهن، روی، مس و منگنز شاخساره علف های هرز نیز به ترتیب در کشت خالص لاین 15-91 وکشت خالص شیرودی (به ترتیب 275 و 6/245 میلی گرم در کیلوگرم) ، کشت خالص شیرودی (5/27 میلی گرم در کیلوگرم) ،کشت خالص لاین 15-91 (23/21 میلی گرم درکیلوگرم) وکشت خالص شیرودی (85/63 میلی گرم درکیلوگرم) مشاهده شد. همچنین بیشترین عملکرد دانه درکشت مخلوط شیرودی + لاین 15- 91 به میزان 4/5 تن در هکتار مشاهده شد. استفاده از کشت مخلوط ارقام گندم می تواند باعث کاهش جذب منابع محیطی به ویژه عناصر کم مصرف توسط علف های هرز و کاهش رشد آن ها شود. نتایج این مطالعه می تواند برای مدیریت غیرشیمیایی و اکولوژیک علف های هرز و افزایش عملکرد گیاه زراعی گندم در اگرواکوسیستم ها مورد استفاده قرار گیرد.
    کلیدواژگان: گرواکوسیستم، تراکم، کشت خالص، مدیریت غیرشیمیایی، منابع محیطی
  • سهیلا قاسمی مهام *، سیف الله فلاح، امیر دادرسی صفحات 805-822
    به منظور بررسی اثر نوع کود و کشت مخلوط ردیفی با شنبلیله (Trigonella foenum-graecum L.) بر عملکرد کمی و کیفی گیاه دارویی اسفرزه (Plantago psyllium L.) ، آزمایشی به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی دانشگاه شهرکرد در سال زراعی 1392 اجرا گردید. در این آزمایش فاکتور اول در چهار سطح که شامل کشت خالص اسفرزه، شنبلیله: اسفرزه (1:2) ، شنبلیله: اسفرزه (1:1) و شنبلیله: اسفرزه (2:1) و فاکتور دوم در سه سطح کودی (کود گاوی، کود تلفیقی، کود شیمیایی) مورد ارزیابی قرار گرفتند. آنالیز داده ها با استفاده از روش تجزیه عامل منجر به انتخاب چهار مولفه جدید شد مولفه پنجم دارای ارزش ویژه 981/0 بود و به همین دلیل در آنالیز داده ها و تفسیر نتایج در نظر گرفته نشد. مولفه های استخراج‍شده با روش کوارتی مکس چرخش یافتند تا بیشترین وزن مولفه روی یک عامل قرار گیرد مولفه های اول، دوم، سوم و چهارم به ترتیب دربرگیرنده 1/31، 22 ، 3/18 و 3/8 درصد تغییرات (واریانس) در کل داده های گیاه اسفرزه بودند و هر سه مولفه در مجموع حدود 7/79 درصد از تغییرات (واریانس) داده ها را به خود اختصاص دادند. همان گونه که در نتایج این تحقیق بیان شد، عامل اول بیشترین تاثیر را به صورت مستقیم بار 971/0، 967/0 و 762/0 درصد به ترتیب روی عملکرد موسیلاژ، موسلاژ و فاکتور تورم داشت. عامل دوم نیز با بار عاملی 93/0، 927/0 و 77/0 درصد از به ترتیب بر روی صفات تعداد شاخه فرعی، وزن هزار دانه و طول سنبله داشت و اما عامل سوم بیشتر اثر بازدارندگی و بار منفی بر عملکرد دانه، تعداد دانه در سنبله و عملکرد بیولوژیک با بار عاملی 902/0-، 884/0- و 837/0- درصد دارا بود. در خصوص عامل چهارم نیز تنها با بار عاملی 973/0 درصد بر تعداد سنبله در بوته داشت. این امر بیانگر تاثیر مثبت و معنی دار عامل دوم در این تحقیق بود. بر اساس نتایج این آزمایش استفاده از کود تلفیقی در برهمکنش با کشت مخلوط شنبلیله و اسفرزه می‎تواند در افزایش مزیت نسبی کشت مخلوط موثر باشد و به لحاظ کاهش مصرف کودهای شیمیایی می تواند در حفاظت از محیط زیست اهمیت داشته باشد.
    کلیدواژگان: تجزیه چند متغیره، کود تلفیقی، گیاه دارویی، همزیستی با گیاهان تثبیت کننده نیتروژن
  • سمیه سهیلی موحد، سعید خماری*، پریسا شیخ زاده، بهرام علیزاده صفحات 823-840
    به منظور بررسی اثر محلول پاشی عناصر کم مصرف بور و روی بر عملکرد و اجزای عملکرد گلرنگ (Carthamus tinctorius L.) بهاره (رقم محلی اصفهان) تحت تنش خشکی آخر فصل، دو آزمایش در مزرعه ی تحقیقاتی دانشگاه محقق اردبیلی، طی سال های زراعی 93-1392 و 94-1393 به صورت اسپیلیت فاکتوریل در قالب طرح پایه بلوک های کامل تصادفی با سه تکرار انجام گرفت. کرت اصلی شامل سه سطح محدودیت آب (=S1 آبیاری کامل تا انتهای فصل، =S2 قطع آبیاری از مرحله ی گلدهی و =S3 قطع آبیاری از مرحله دانه بندی) و کرت فرعی دربرگیرنده ترکیب فاکتوریل عناصر ریز مغذی بور (0B1=، 350 B2=و 700B3= میلی گرم بر کیلوگرم) و روی (0Zn1=، 1000Zn2= و 2000Zn3= میلی گرم بر کیلوگرم) بود. صفات مورد ارزیابی شامل ارتفاع بوته، تعداد طبق بارور در بوته، تعداد طبق نابارور در بوته، تعداد دانه در طبق، تعداد دانه در بوته، درصد پوکی دانه، وزن هزاردانه، عملکرد دانه، عملکرد بیولوژیک و شاخص برداشت بودند. نتایج نشان داد که تنش خشکی در مرحله گلدهی و دانه بندی به صورت معنی داری عملکرد دانه را نسبت به تیمار شاهد (آبیاری کامل) کاهش داد (به ترتیب 94/7 و 25/8 درصد). علاوه بر آن وزن هزار دانه، تعداد دانه در بوته و عملکرد بیولوژیک نیز تحت اثرات منفی تنش خشکی قرارگرفتند. اثرات متقابل عناصر ریز مغذی بور و روی، در تمام صفات مورد بررسی به جز عملکرد بیولوژیک و ارتفاع بوته معنی دار بود. تیمار B3Z2بالاترین افزایش عملکرد دانه را نسبت به B1Z1 (شاهد) دارا بود (66/47 درصد). محلول پاشی عناصر بور و روی در شرایط تنش در مرحله ی گلدهی و دانه بندی، تعداد طبق نابارور در بوته، وزن هزار دانه و درصد پوکی دانه را، به طور معنی داری بهبود بخشید. وجود همبستگی مثبت و معنی دار بین عملکرد و سایر صفات مورد مطالعه نشان داد که محلول پاشی عناصر ریزمغذی اگر در زمان مناسب و به مقدار بهینه مصرف گردد، در مقاومت به خشکی گیاه اثر مثبت خواهد گذاشت. به طور کلی تیمارهای B3Z2 و B2Z2 در شرایط تنش در مرحله گلدهی (به ترتیب با افزایش عملکرد 8/54% و 8/55% نسبت به تیمار B1Z1) و دانه بندی (به ترتیب با افزایش عملکرد 5/39% و 4/38% نسبت به تیمار B1Z1) توانستند تا حدود زیادی خسارت ناشی از محدودیت آب را در گلرنگ را جبران کنند.
    کلیدواژگان: عناصر ریز مغذی، مرحله گلدهی، مقاومت به خشکی
  • اعظم گیدسکی، رضا برادران * صفحات 841-851
    به منظور بررسی اثر دور آبیاری و محلول پاشی عناصر کم مصرف روی گیاه ارزن معمولی (Panicum miliaceum L.) آزمایشی به صورت کرت های خرد شده، در قالب طرح بلوک کامل تصادفی با سه تکرار در مزرعه ای در منطقه ی سربیشه از توابع شهرستان بیرجند در سال 1391 انجام شد. تیمارهای آزمایش شامل دور آبیاری در سه سطح (7، 14 و 21 روز) و محلول پاشی عناصر کم مصرف به چهار روش (محلول پاشی منگنز، محلول پاشی روی، محلول پاشی توام منگنز و روی و بدون محلول پاشی) به ترتیب به کرت های اصلی و فرعی اختصاص یافت. نتایج نشان داد که کاهش دور آبیاری عمدتا از طریق افزایش صفات مورفولوژیک مانند ارتفاع گیاه، تعداد برگ در بوته، مساحت برگ پرچم، طول پدانکل و طول خوشه سبب افزایش عملکرد دانه شد. محلول پاشی عناصر کم مصرف روی و منگنز نیز با افزایش ارتفاع گیاه، تعداد برگ در بوته، طول پدانکل و طول خوشه سبب افزایش عملکرد دانه شد. اثر تیمار دور آبیاری بر صفت شاخص برداشت دانه در خوشه معنی دار بود. کاهش دورآبیاری سبب افزایش شاخص برداشت دانه در خوشه شد (96/17 درصد نسبت به تیمار با دور آبیاری 21 روز). اثر محلول پاشی عناصر کم مصرف بر صفت شاخص برداشت دانه در خوشه معنی دار بود. تیمار محلول پاشی عناصر کم مصرف سبب افزایش شاخص برداشت دانه در خوشه شد. اثر متقابل دور آبیاری و محلول پاشی عناصر کم مصرف نیز در سطح 5 درصد معنی دار شد. بیشترین عملکرد دانه مربوط به تیمار دور آبیاری 7 روزه و محلول پاشی توام منگنز و روی با 6/222 گرم در متر مربع بود. کم ترین عملکرد دانه هم مربوط به تیمار دور آبیاری 21 روز و بدون محلول پاشی بود. کاهش دور آبیاری به 7 روز و محلول پاشی عناصر کم مصرف سبب افزایش صفات مورفولوژیک، شاخص برداشت دانه در خوشه و عملکرد دانه شد. در شرایط تنش خشکی محلول پاشی عناصر کم مصرف روی و منگنز سبب افزایش صفات مورفولوژیک و نهایتا عملکرد دانه گردید.
    کلیدواژگان: دور آبیاری، شاخص برداشت، عملکرد دانه، محلول پاشی
  • رضا عارفی *، افشین سلطانی، حسین عجم نوروزی صفحات 853-873
    این تحقیق به بررسی انرژی مصرفی، میزان سوخت مصرفی و برآورد شاخص های انرژی در تولید پنبه در شهرستان های علی آبادکتول و آق قلا در استان گلستان ایران پرداخته است. اطلاعات از طریق مصاحبه حضوری با 100 پنبه کار جمع آوری شد. در این مطالعه مقادیر مصرف سوخت و انرژی برای هر یک از عملیات زراعی مرتبط با تولید پنبه در علی آباد و آق قلا مورد بررسی قرار گرفت. نتایج نشان داد که بیشترین مصرف انرژی با 41 درصد از کل انرژی مصرفی مربوط به عملیات آبیاری بود و عملیات های تغذیه و آماده سازی زمین در رتبه های بعدی می باشند مجموعه انرژی نیروی کارگری 2262 مگا ژول در هکتار محاسبه شد که به ترتیب عملیات برداشت، عملیات آبیاری و عملیات وجین، سله شکنی و واکاری از بیشترین به کمترین مصرف انرژی کارگری را داشتند. 61 درصد از کل انرژی (10217 مگا ژول در هکتار) به طور غیر مستقیم برای ساخت، تعمیر و نگهداری ادوات و ماشین آلات، تولید بذر، تولید کود نیتروژن، تولید کودهای فسفر، تولید کود های پتاسیم، تولید کود های آلی، تولید حشره کش ها، تولید علف کش ها و تولید قارچ کش ها مصرف شده است. تولید کود نیتروژن با 30 درصد بیشترین سهم را نسبت به سایر بخش های انرژی های غیر مستقیم داشت در حالی که 39 درصد از کل انرژی های مصرفی مربوط به انرژی های مستقیم و از طریق بکارگیری نیروی انسانی و مصرف سوخت مصرف شده است. متوسط نسبت انرژی در مجموع مزارع برابر با 92/5 بود. نتایج بررسی مقادیر کل انرژی ورودی در مزارع نشان داد که کمترین و بیشترین انرژی ورودی کل به ترتیب برابر 15614 و 43321 مگا ژول در هکتارمحاسبه شد. میانگین عملکرد وش 8/2 تن در هکتار بدست آمد که این مقدار معادل 154371 مگا ژول در هکتار انرژی می باشد.
    کلیدواژگان: انرژی خروجی، انرژی مستقیم، انرژی ورودی، نیروی انسانی
  • آرش محمدزاده، عبدالمجید مهدوی دامغانی*، جواد وفابخش، رضا دیهیم فرد صفحات 875-895
    استفاده بهینه از منابع و نهاده ها یکی از اولین و اساسی ترین اهداف توسعه کشاورزی پایدار است. در پژوهش حاضر، پایداری بوم نظام های زراعی یونجه (Medicago sativa L.) و ذرت علوفه ای (Zea mays L.) دشت مراغه– بناب استان آذربایجان شرقی در سال 1394-1393 مورد ارزیابی قرار گرفت. بدین منظور، اطلاعات مورد نیاز تحقیق با استفاده از پرسشنامه و مصاحبه حضوری با 110 کشاورز به دست آمد. نتایج نشان داد که کل انرژی ورودی، خروجی و انرژی خالص در بوم نظام های یونجه (به ترتیب 48151، 432920 و 384768 مگاژول در هکتار) بیشتر از ذرت علوفه ای (به ترتیب 35557 ، 217350 و 181792 مگاژول در هکتار) بود. همچنین، شاخص های کارایی مصرف انرژی و انرژی مخصوص در یونجه (به ترتیب 9 و 8/15 مگاژول بر کیلوگرم) مقادیر بالاتری از ذرت علوفه ای (به ترتیب 1/6 و 1/4 مگاژول بر کیلوگرم) را نشان داد. از نظر شاخص های اقتصادی، علی رغم پایین بودن هزینه کل تولید در ذرت علوفه ای (1089 دلار در هکتار) ، بیشترین ارزش ناخالص تولیدی (6447 دلار در هکتار) و سود خالص (4193 دلار در هکتار) برای یونجه محاسبه گردید. مقایسه بوم نظام ها نشان داد که در واحد سطح، تولید یونجه در مقایسه با ذرت علوفه ای اثر بیشتری بر گرمایش جهانی داشته و نیز اثرات محیط زیستی بیشتری را ناشی از مصرف آفت کش ها بر جای می گذارد. با این وجود، از نظر شاخص کارایی اکولوژیک، ارزش ناخالص محصول یونجه به ازای اثر محیط زیستی ایجاد شده (75/1 دلار بر کیلوگرم CO2 در هکتار و 3/35 دلار بر eq.) بیشتر از ذرت علوفه ای (5/1 دلار بر کیلوگرم CO2 در هکتار و 26 دلار بر eq.) به دست آمد. به عبارتی، اثرات محیط زیستی ناشی از تولید یونجه در واحد سطح بیشتر از ذرت علوفه ای و به ازای ارزش محصول تولیدی کمتر از ذرت علوفه ای می باشد. شاخص های بهره وری زمین، بهره وری اقتصادی زمین، بهره وری آب آبیاری، بهره وری اقتصادی آب آبیاری و کارایی استفاده از کودهای نیتروژن، فسفر و پتاسیم به ترتیب برای یونجه 140 کیلوگرم در هکتار در روز، 5/21 دلار در هکتار در روز، 1/4 کیلوگرم در متر مکعب، 63/0 دلار در متر مکعب، 335 کیلوگرم در کیلوگرم، 1191 کیلوگرم در کیلوگرم و 1826 کیلوگرم در کیلوگرم و برای ذرت علوفه ای 583 کیلوگرم در هکتار در روز، 9/22 دلار در هکتار در روز، 8 کیلوگرم در متر مکعب، 31/0 دلار در متر مکعب، 565 کیلوگرم در کیلوگرم، 3553 کیلوگرم در کیلوگرم و 65525 کیلوگرم در کیلوگرم به دست آمد. به طور کلی، نتایج نشان داد که تولید یونجه علی رغم مصرف انرژی بیشتر و اثرات محیط زیستی بالا در واحد سطح، از نظر اقتصادی بر تولید ذرت علوفه ای برتری دارد.
    کلیدواژگان: آفت کش، بهره وری آب، کارایی انرژی، کارایی مصرف کود، گرمایش جهانی
  • سعیده رحیم زاده، علیرضا پیرزاد * صفحات 897-911
    رابطه بین قارچ مایکورایزا و باکتری های مرتبط با آنها، بدلیل جایگزینی با کودهای شیمیایی اهمیت زیادی در کشاورزی پایدار دارد. به منظور بررسی اثرات احتمالی قارچ های مایکورایزا در ارتباط با باکتری حل کننده فسفر روی کیفیت بذر حاصل از گیاهان کتان (Linum usitatissimum L.) ، آزمایشی بصورت فاکتوریل بر پایه بلوک کامل تصادفی با سه تکرار در مزرعه تحقیقاتی دانشگاه ارومیه بصورت دو ساله انجام شد. تیمارهای آزمایش شامل گونه های قارچ مایکورایزا (Rhizophagus intraradices، Funneliformis mosseae و عدم تلقیح) ، باکتری حل کننده فسفر (تلقیح بذر با Pseudomonas putida P13 و عدم تلقیح) و سه رژیم آبیاری (آبیاری پس از 60، 120 و 180 میلی متر تبخیر از تشتک تبخیر) بودند. نتایج نشان داد با افزایش فاصله آبیاری از 60 تا 120 میلی متر، در گیاهان شاهد (بدون تلقیح) ، درصد فسفر، پتاسیم، موسیلاژ، و فاکتور تورم و تورم برای هر گرم موسیلاژ بذر، همچنین پتاسیم تراوشی بذر (شاخص صدمه به غشای سلولی) افزایش و با بیشتر شدن تنش در 180 میلی متر کاهش یافتند. در کلیه سطوح آبیاری، هم افزایی ناشی از تلقیح توام قارچ و باکتری باعث بیشترین درصد فسفر، پتاسیم، موسیلاژ و تورم موسیلاژی بذر شد. درصد و سرعت جوانه زنی در بذور حاصل از تلقیح، با توجه به افزایش حجم موسیلاژ بذر، روند نزولی داشت. البته در تنش شدید بیشترین سرعت و درصد جوانه زنی از تلقیح توام بدست آمد. بنابراین از نظر موسیلاژ و جوانه زنی، می توان بسته به هدف تولید، دو نوع کیفیت برای بذر کتان تعریف کرد. به طور کلی بیشترین افزایش در بهبود کیفیت بذر از نظر عناصر غذایی، پروتئین بذر و تولید موسیلاژ، در تلقیح توام گیاهان با قارچ و باکتری مشاهده شد.
    کلیدواژگان: تنش خشکی، جوانه زنی بذر، سودوموناس، قارچ مایکورایزا، موسیلاژ
  • سارا اسدی، محمد بنایان اول*، محسن جهان، علیرضا فرید حسینی صفحات 913-924
    توانایی دقیق و سریع به دست‎آوردن شاخص سطح برگ (LAI) یک جزء ضروری در تحقیقات بوم شناختی است که به درک پدیده تولید زیست توده گیاهی کمک می‎کند. یکی از رایج‎ترین روش‎های تعیین تغییرات مکانی و زمانی این شاخص در مقیاس منطقه‎ای، استفاده از شاخص تفاضل نرمال‎شده بازتابش سطحی (NDVI) است. با توجه به حساسیت کم این شاخص به مقدار متوسط تا زیاد شاخص سطح برگ، این تحقیق با هدف بررسی ارتباط سایر شاخص‎های پوشش گیاهی با شاخص سطح برگ گندم (Triticum aestivum L.) و دقت آن‎ها در برآورد شاخص سطح برگ انجام شد. بدین منظور اندازه‎گیری شاخص سطح برگ در پنج تاریخ از 17 مزرعه واقع در مزارع آستان قدس رضوی مشهد در طول فصل رشد گندم در سال 1394-1393 صورت گرفت. با توجه به طول دوره رشد گندم از تصاویر سری زمانی سنجنده OLI ماهواره لندست 8 به‎منظور محاسبه شاخص‎های پوشش گیاهی (NDVI، DVI، EVI1، EVI2، G1، G2، IPVI، SAVI، TDVI و RVI) استفاده شد. برای انتخاب متغیر برآورد کننده مناسب و مدل‎سازی آماری از روش رگرسیون ساده (خطی، درجه دوم، نمایی) و رگرسیون خطی دوگانه و رگرسیون خطی چندگانه به روش پیش‎رونده و پس‎رونده استفاده شد. در نهایت برای اعتبارسنجی و درستی مدل های ارائه شده از سنجه های آماری جذر میانگین مربعات خطا (RMSE) ، میانگین قدر مطلق خطا (MAE) ، دقت نقطه‎ای نسبت به مقدار واقعی (E) و ضریب همبستگی (r) استفاده شد. نتایج حاکی از افزایش دقت برآورد شاخص سطح برگ گندم با استفاده از شاخص NDVI و SAVI و توابع نمایی (به ترتیب به 18/1 و 1) نسبت به مدل خطی (به ترتیب 46/1 و 26/1) است. این افزیش دقت به دلیل برآورد دقیق‎تر شاخص سطح برگ در بازه 0 تا 4 شاخص سطح برگ واقعی و مقدار ثابت شاخص سطح برگ شبیه‎سازی در بازه شاخص سطح برگ واقعی 6 تا 10 می‎باشد. لازم به ذکر است که، میزان دقت برآورد شاخص سطح برگ با استفاده از ترکیب این دو شاخص نسبت به مدل خطی هر کدام از این شاخص ها افزایش یافته است. هم چنین، بالاترین دقت در برآورد شاخص سطح برگ از ترکیب شاخص G2 با SAVI و EVI1 (به ترتیب 03/1، 03/1) به دلیل حساسیت بیشتر شاخص G2 به شاخص سطح برگ متوسط و بالا نسبت به NDVI مشاهده شد. علاوه بر این دقت مدل گزینش پیش‎رونده و پس‎رونده نسبت با سایر مدل‎ها در برآورد شاخص سطح برگ، به دلیل حساسیت بیشتر مدل به شاخص سطح برگ بالاتر از 6، بهبود یافته است (به ترتیب 87/0 و 95/0). اگرچه دقت برآورد شاخص سطح برگ گندم در روش گزینش پیش‎رونده نسبت به تمامی مدل‎ها بیشتر است، اما محاسبه آن نیاز به استفاده از پارامترهای زیادی است.
    کلیدواژگان: رگرسیون چند متغیره، شاخص‎های تعدیل شده پوشش گیاهی، شاخص تفاضل نرمال‎شده، شاخص رشد گیاهی
  • عبدالله ملافیلابی *، تهمینه اسفندیاری صفحات 935-948
    زیره سبز (Cuminum cyminum L.) گیاهی علفی از خانواده چتریان است که سابقه طولانی به عنوان طعم دهنده های غذایی و در درمان بیماری ها دارد. این آزمایش با هدف بررسی رژیم های مختلف آبیاری و تاریخ کاشت بر درصد اسانس، عملکرد و اجزای عملکرد زیره سبز به صورت کرت های خرد شده در قالب طرح بلوک های کامل تصادفی در مزرعه تحقیقاتی دانشگاه آزاد اسلامی واحد بیرجند در سال زراعی 96-1395 اجرا شد. چهار تاریخ کاشت به عنوان عامل اصلی (5 آذر، 7 دی، 1 اسفند و 29 اسفند) و چهار رژیم آبیاری به عنوان عامل فرعی (آبیاری کامل، دو نوبت آبیاری در زمان رشد رویشی (ساقه رفتن) ، دو نوبت آبیاری در زمان گلدهی و دو نوبت آبیاری در زمان دانه بندی) به عنوان تیمار در نظر گرفته شد. صفات مورد مطالعه شامل وزن بوته، وزن دانه، تعداد چتر در گیاه، تعداد دانه در چتر، تعداد دانه در بوته، وزن هزار دانه و درصد اسانس تعیین بود. نتایج نشان داد که اثر متقابل تاریخ های مختلف کاشت و رژیم های آبیاری بر تعداد شاخه جانبی و عملکرد دانه و عملکرد بیولوژیک معنی دار بود. اثر ساده تاریخ کاشت بر تعداد دانه در چتر، ارتفاع بوته، درصد اسانس، وزن هزار دانه و شاخص برداشت معنی دار بود. بیشترین عملکرد دانه و عملکرد بیولوژیک در تاریخ کاشت 7 دی ماه همراه با آبیاری کامل به دست آمد. نتایج همبستگی بین صفات نشان داد که بین عملکرد و اجزای عملکرد همبستگی مثبت و معنی داری مشاهده شد. همچنین عملکرد دانه بیشترین همبستگی (95/0r=) را با عملکرد بیولوژیک داشت.
    کلیدواژگان: آبیاری کامل، خشکی، کمبود آب، وزن هزار دانه
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  • S. Khorramdel*, P. Rezvani Moghaddam, H. Azizi, J. Shabahang, M. Seyedi Pages 603-619
    Introduction
    Medicinal plants have an important role in different industries. So, increasing production of their yields is necessary. Medicinal plants contain phytochemical compounds which have demonstrated bioactive properties. The active principles of the plants are generally secondary metabolites. The use of ecological farming methods, may improve yield and quality. In the last decade, agricultural production, which is mainly based on the use of chemical material, is causing environmental problems. One of the pathways to mitigate this environmental impacts, is to apply the long-term approaches based on the principles of ecological agriculture. Soil microorganisms are the primary metabolites production in the soil can affect the results in the release of phosphorus. Compost can be used as an organic matter in controlling different types of debris and the reduction in fertilizer consumption in agricultural products and mineral absorption elements improve low consumption by plants. Present study aims to investigate the possibility of improving the growth, flower yield, shoot yield, seed yield and yield components of marshmallow as a medicinal plant affected as integrated management of organic, chemical and biological fertilizers.
    Materials and Methods
    A field experiment was performed as factorial layout based on a randomized complete block design with three replications at Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad, Iran, during growing season of 2012-2013. The experimental treatments were all combination of organic and chemical fertilizers in four levels (cow manure (40 ton.ha-1), urban compost (40 ton.ha-1), NPK as chemical fertilizer (114, 18 and 220, 40 kg.ha-1) and control) and inoculation with Thiobacillus and sulphur application in four levels (including inoculation with Thiobacillus, 200 kg.ha-1 sulphur + inoculation with Thiobacillus, 200 kg.ha-1 sulphur and control). plant height, leaf areal indexmax (LAImax), leaf dry weight, stem dry weight, total dry weight, flower, seed yield and yield components such as branch number, capsule number, number seed per capsule and 1000-seed weight and flower, seed and biological yield of marshmallow.
    To analyze the variance of the experimental data and drawing of diagrams, MSTAT-C 8 and Excel software was used. All the averages were compared according to Duncan’s multiple range test (p≤0.05)
    Results and Discussion
    The results showed that the effect of organic, chemical and biological fertilizers were significant (p≤0.01) on plant height, LAImax, leaf dry weight, stem dry weight, total dry weight, flower and seed yield, yield components and biological yield of marshmallow. At the end of the growing season, the highest and the lowest LAImax were observed in chemical fertilizer with Thiobacillus +sulphur (12.3) and control (1.3). The maximum flower and seed yields were recorded in chemical fertilizer with Thiobacillus +sulphur (175.33 and 99.91 g.m-2, respectively) and the minimum were obtained in control treatments (32.33 and 9.31 g.m-2, respectively). Flower yield enhanced up to 100% under chemical, cow manure and compost fertilizers without Thiobacillus +sulphur, Thiobacillus, sulphur compared to control treatment. Flower yield improved up to 106, 89 and 72% for chemical fertilizer, cow manure and compost application with Thiobacillus +sulphur, respectively.
    Conclusion
    According to the results obtained in the present study, organic, chemical and biological fertilizers had significant effects on growth, shoot yield, flower yield, seed yield, biological yield and yield components of marshmallow. Therefore, due to the high pH of soils in agroecosystems, integrated application of sulphur with Thiobacillus inoculation could be considered as an effective approach for soil fertility improvement. organic matter increase soil water holding capacity, improving plant hormone-like activity, increase nutrient uptake by plants, and generally improve the growth and yield of medicinal plant.
    Keywords: Soil fertility, Soil pH, Sustainable agriculture, Thobacillus
  • Seyyedeh Saide Zendebad , Parviz Rezvani Moghaddam *, Reza Ghorbani , Reza Khorasani Pages 621-634
    Introduction
    Dill (Anethum graveolens L.) is an annual medicinal plant belonging to the Apiaceae family and is native to the Southwest and Central Asia. This plant is not susceptible to cold and germination occurs at low temperatures. The vegetative period of this plant is short and from seed emergence till the fruit harvesting reaches 100 to 120 days. Based on long-term studies, excessive use of chemical fertilizers has a negative effect on plant yield resulting soil acidification, negative effect on soil biological activity and physical and chemical properties. In addition, application of chemical fertilizers mean while environmental impacts increases production costs in the long term. According to literatures, the use of organic or biological fertilizers to reduce the mentioned problems can be especially valued.
    Materials and Methods
    In order to investigate the effects of organic, chemical fertilizers and mycorrhizae inoculation on yield and yield components of dill in different cuts, an experiment was carried out in the Research Station, College of Agriculture, the Ferdowsi University of Mashhad, in 2013. The experiment was carried out in a factorial experiment based on randomized complete block design with three replications. The treatments were all combination of organic and chemical fertilizers in four levels (cow manure, vermicompost, chemical fertilizer and control) and three levels of Mycorrhiza inoculation (Glomus mosseae, Glomus intraradices and no inoculation). The collected data were analyzed as split- plot design in time based on randomized complete block design (due to having three cuts during growing season). The 12 fertilizer treatments and three cuts were considered as main and sub plots, respectively.
    Results and Discussion
    The results showed that the highest (4259 kg.ha-1) and the lowest fresh yield (2043 kg.ha-1) were obtained in second cut and third cut, respectively. The results indicated that Leaf Area Index, fresh and dry matter yield, percentage and essential oil yield were significantly different between inoculated mycorrhizae treatments and control treatment. However, there was no significant difference (p<0.05) between Glomus mosseae and and Glomus intraradices in terms of former mentioned criteria. Fresh and dry matter yield and essential oil yield of dill were significantly higher in organic fertilizers treatments (vermicompost and cow manure) compared with chemical fertilizer. The results showed that using organic fertilizers have a better performance than chemical fertilizers in growing dill both in quality and quantity. The effects of fertilizer and mycorrhiza on leaf/stem ratio, grain yield, dry matter yield and essential oil yield were significant. The results of the experiment showed that in each level of mycorrhizal application, the use of vermicompost increased the leaf/stem ratio, so that, underGlomusintraradices inoculum conditions, the use of this organic fertilizer resulted in an increase of 16% leaf/stem ratio compared to the control. Also, in the absence of mycorrhizal inoculation, vermicompost and animal manure application resulted in a significant increase in leaf/stem ratio. The results of the experiment showed that the fresh and dry yield of the vegetative parts of the drill were significantly higher than other treatments in inoculation of mycorrhizal and animal manure treatments, so that the application of the mentioned treatment, fresh and dry yield of the vegetative parts increased by two times compared with control treatment. In addition, the results of the experiment showed that the essential oil yield increased as a result of the combined application of animal manure and mycorrhizal treatments, so that the application of vermicompost fertilizer and G. mosseae compared to control treatment increased the essential oil yield by more than four times.
    Conclusion
    According to the results of the experiment, mycorrhizal application has an important role in improving the growth characteristics and dry matter yield, especially in cut II and III. In addition to mycorrhizal inoculation, application of livestock manure and vermicompost can play an important role in increasing the yield of drill at different cutting. Combined use of mycorrhiza inoculum and organic fertilizers can reduce the problems caused by the use of chemical fertilizers.
    Keywords: Cutting, Essential oil, Vermicompost
  • Alireza Koocheki *, M. Nassiri Mahallati , Abdolah Molafilabi , Ali Noroozian Pages 635-646
    Introduction
    Saffron (Crocus sativus L.) as a spice crop, additive, and flavoring is applied in food industries. Saffron also is applied in medicine as a drug. It has a specific site in Iran exports, so that 90% of saffron production belongs to Iran. In 2016 Iran has been the largest producer of saffron with 336 ton and cultivation area of 105270 ha. Provinces of Khorasan-Razavi and Southern Khorasan are the two main centers of saffron production in Iran. Environmental factors have considerable effects on quantitative and qualitative characters of saffron. Low yield of saffron in traditional farming systems can be due to application of small size corms. Corm size or corm weight is one of the most important factors affecting saffron yield. Research in this regard and finding out a standard size for planting saffron are among research directions for saffron research and development.
    Materials and Methods
    This experiment was arranged as randomized complete block design (RCBD) with 10 treatments and three replicates at the research farm of college of agriculture, Ferdowsi University of Mashhad (latitude 36 and 16 north and longitude 59 and 36 east and altitude 985m) in cropping year of 2012-2013. Ten weight groups of mother corms were as follows: <2, 2.1-6, 6.1-10, 10.1-12, 12.1-14, 14.1-16, 16.1-18, 18.1-20, 20.1-24 and >24 g as treatments. Land preparation included primary plough, disc and leveler and then to plot the land as 1×1 m with between rows 20 cm as plant density of 50 corms.m-2. Picking saffron flowers occurred in late October as daily basis and corm lifting occurred in June. Measured characters were, number of corms without flowers, number of one flower corms, number of double flower corms, number of three flower corms, four flower corms and higher ones, total number of sister corms, number of sister corms in weight groups of <4, 4-8, 8-12, and >12 g. Data analysis was performed with SAS 9.1 and mean comparisons with duncan’smultiple range test at p ≤0.0 5.
    Results and Discussion
    Corm weight is very important in flowering capacity of saffron. So, by increasing weight of mother corm, number of flowers may improve. Based on results obtained from variance analysis, number of saffron flowers was affected significantly by weight corms of mother corms (p≤0.01). By increasing corm weight number of saffron flowers increased so that corms less than 2 g produced least flowers and highest number of flowers related to 20.1-24 and 24 g corms with 1250000 and 1300000 flowers.ha-1. These findings have been confirmed another place. Findings of this research showed that the most critical factor affecting saffron flowering is corm weight that is among the few factors affect flowering. We know that there is a positive relationship between corm diameter and corm weight. Some authors apply corm diameter and some other use corm weight but most authors use corm weight.
    Conclusion
    It was concluded that increasing weight of mother corms through increasing number of sister corms caused to increase number of flowers that finally was followed by improvement of dry stigma. Increasing mother corm weight had positive effects on all vegetative and reproductive characters of saffron.
    Keywords: Daughter corm, Dry weight of stigma, Fresh weight of stigma, Number of flower
  • M. Nassiri Mahallati *, A. Koocheki Pages 647-665
    Introduction
    Crop response to nitrogen (N) is usually evaluated by N use efficiency and diminishing return curves between yield and applied N fertilizers. However, both methods are highly variable due to environmental conditions and are dependent to the amount, timing and type of N fertilizers. Extending the results of such studies will led to overestimation of crop N requirements as a result of differences in precipitation, temperature and radiation across locations and years. Therefore optimizing fertilizer use for maximum productivity should be based on methods with higher certainty. Nitrogen nutrition index i.e. the ratio of actual N concentration in plant tissues to the critical N concentration is more reliable measure for fertilizer recommendation because of its stability over environmental fluctuations. However, for development of N nutrition index the critical dilution cure should be specifically established for each crop. In this papers N nutrition index is estimated for different wheat cultivars and tested for evaluation of grain yield in response to N application rates.
    Materials and Methods
    To determine N nutrition index for wheat cultivars, a field experiment was conducted with factorial arrangement based on complete randomized block design with three replications. Experimental factors included three wheat cultivars (Chamran, Gaskogen and Sionez) and four N application rates (0, 55, 110 and 170 kg N ha-1). Shoot dry matter and N concentration was measured in five sampling during vegetative growth period. Using these data critical N concentrations and critical N dilution curves were calculated and compared with the previously established reference dilution curve for wheat crop. Nitrogen nutrition index (NNI) was then calculated as the ratio between measured shoot N (%) and the critical N concentration. Using NII grain yield and protein content of wheat cultivars was compared under different levels of N fertilizer.
    Results and Discussion
    Critical concentration of nitrogen was slightly underestimated by the curve obtained in this study compared to reference curve. However, estimated coefficients of the dilution curve were closed to those of reference curve of wheat crop. Overall, nitrogen deficiency, sufficiency and excess in shoot dry matter were properly described by the estimated critical dilution and critical uptake curves. All wheat cultivars were nitrogen limited in no fertilized control and with application of 55 kg N ha-1 however, in 170 kg N ha-1 shoot nitrogen content was more than amount required for optimal growth and in 110 kg N ha-1 nitrogen uptake was closed to critical values. In unfertilized control and 55 kg N ha-1 NNI was lower than 1 during the whole vegetative growth period. However, in 110 kg N ha-1 NNI was almost 1 and in 170 kg N ha-1 varied between 1-1.3. A significant relation was obtained between NNI at flowering and relative yield of wheat cultivars and grain yield of three cultivars reached to its maximum at NNI between 0.9-1. Grain protein was also linearly correlated with NII at flowering.
    Conclusion
    Based on the results nitrogen nutrition index calculated from critical dilution curve could be used as a powerful tool for precise estimation of crop growth rate, dry matter accumulation, grain yield and protein and to optimize the amount of N fertilizer required for any predefined yield level
    Keywords: Critical N concentration, Critical N dilution curve, Critical N uptake, Grain yield, Grain protein
  • Sarhad Bahrabmi , Weria Weisany * Pages 665-678
    Introduction
    Cereals and legumes are considered as important forage crops, because of their nutritional value, especially protein content in legumes and crude fiber in cereals. Intercropping may be a useful strategy to grow crops simultaneously, offering to improve resource utilization such as solar radiation, nutrients and water during growth and development. This is also an important method for sustainable crop production, particularly when inputs are limited. Higher yields have been documented for intercropping of beans and maize, barley and peas, oats and vetches wheat and peas, and wheat and beans. Using time and space, in addition, improving plant production methods in terms of environmental and human health, intercropping can increase agricultural production. In order to increasing soil fertility and improving plant growth and quality, in medicinal plants cultivation, elimination or reduction of chemical fertilizers, is very important. In terms of competition, this means that the components are not competing for the same ecological niches and then the interspecific competition is weaker than the intraspecific competition for a given factor. Intercrops can be more effective than sole crops in preempting resources used by weeds and suppressing weed growth, because complementary patterns of resource use and facilitative interactions between intercrop components can lead to a greater capture of light, water, and nutrients. Several indices such as land equivalent ratio (LER), time equivalent ratio (ATER), and relative value total (RVT), land utilization efficiency (LUE), relative crowding coefficient (K), and aggressivity (A) are used to describe the competition and the economic advantage of intercropped plants.
    Materials and Methods
    In order to study the effect of plant density and intercropping ratio of annual forage legumes includes: grass pea (Lathyrus sativus L.), field pea (Pisum avestum L.), hairy vetch (Vicia villosa L.) and hungarian vetch (Vicia pannonica L.) on quantitative and qualitative barley performance in a randomized complete block design with three replications were conducted in Kurdistan Agricultural Research (Sanandaj) stations under rainfed condition during 2013 growing season. The treatments included five levels of legume seed densities (100, 150, 200, 250, 300 plant.m-2) and four seeding ratios (100% legume, 75% legume + 25% barley, 50% legume + 50% barley and 100% barley).In this experiment, fresh forage yield, dry matter, crude protein yield and land equivalent ratio (LER) were recorded. The crops were managed according to organic farming practices without pesticide or fertilizer use. No mechanical weeding was performed after sowing. Combined analysis of variance was performed using SAS version 9.1 (SAS Institute Inc., Cary, NC, USA) (SAS Institute Inc. 1988). Means of the treatments were compared, using Generalized Linear Model (GLM) method and the least significant difference (LSD) test at the 5% probability level. The data showed normal distribution and no transformation was required.
    Results and Discussion
    Results showed that the highest and lowest fresh forage yield and dry matter yield were obtained from pure barley and pure legumes in 100 plant.m2 seed density, respectively. Intercropping ratio of 75% field pea+ 25% barley at 250 plant.m-2 density and 50% hairy vetch+ 50% barley at 300 plant.m-2 density with 0.94 and 0.86 t.ha-1 produced maximum crude protein yields, respectively. Intercropping ratio of 75% grass pea+25% barley at 300 plant/m-2 density, 75% field pea+ 25% barley at 200 plant.m-2 density, 50% hairy vetch+ 50% barley at 300 plant.m-2 density and 50% hungarian vetch+ 50% barley at 200 plant.m-2 density, with 1.19, 1.26, 1.16 and 1.13 LER values, respectively, performed the best efficiency in resources utilization in intercropping system.
    Conclusion
    Based on these results, it can be concluded that intercropping of annual forage legumes includes: grass pea, field pea, hairy vetch and hungarian vetch with barley is a way for increasing productivity per unit area.
    Keywords: Forage quality, Land equivalent ratio, Poaceae, Yield
  • Mohammad Behzad Amiri , Parviz Rezvani Moghaddam *, Mohsen Jahan Pages 679-698
    Introduction
    In recent years, the effect of ecological inputs on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in terms of plant productivity, this approach is often inefficient in the long-term in tropical ecosystems due to the limited ability of low-activity clay soils to retain nutrients. Biofertilizer is a substance which contains living microorganisms which, as applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Biofertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorous and stimulating plant growth through the synthesis of growth-promoting substances. Biofertilizers can be expected to reduce the use of chemical fertilizers and pesticides. Humic substances are a group of heterogeneous molecules that are bonded together by weak forces; therefore, they have a high chemical stability. This material included of 65 to 80 percent of total soil organic matter. Humic acid influences soil fertility through its effect on the water-holding capacity of the soil. Humic acids make important contributions to soil stability and soil fertility leading to exceptional plant growth and micronutrient uptake. Mycorrhiza arbuscular fungi are other coexist microorganisms that improves soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Echium amoenum is a wild perennial herb and known in Iran as Ox-Tongue. It is one of the important medicinal plants in Iranian traditional medicine. Petals of Iranian Ox-Tongue have been advocated for a variety of effects such as demulcent, anti-inflammatory and analgesic, especially for common cold, anxiolytic, sedative and other psychiatric symptoms including obsession in folk medicine of Iran. Despite of many researches on the effect of organic acids and biofertilizers on different crops, information on the effects of these factors for many medicinal plants is scarce, therefore, in this study effect of eco-friendly inputs in cultivation of Echium amoenum in conditions of Mashhad was studied.
    Materials and Methods
    In order to evaluate organic acids, plant growth rhizobacteria and different species of mycorrhiza on yield and yield components of Iranian Ox-Tongue (Echium amoenum), a split plots experiment in time based on RCBD design with three replications was conducted in 2011-2014 growing seasons, in Ferdowsi University of Mashhad, Iran. Seven different types of soil amendments and biofertilizers concluded humic acid, fulvic acid, Nitroxin® (containing Azotobacter spp. And Azospirillum spp.), Biophosphorous® (containing Bacillus sp. and Pseudomonas sp.), Biosulfur® (containing Thiobacillus spp.), Mycorrhiza (Glomus mosseae), Mycorrhiza (Glomus intraradices), and no fertilizer as control and agronomic years (2 and 3 agronomic years) assigned to main and sub plots, respectively.
    Result and Discussion
    The results showed that the highest dry flower yield obtained in humic acid treatment. Humic acid and fulvic acid increased seed weight per plant 38 and 25% and seed number per plant 19 and 17% compared to control, respectively. Fulvic acid, nitroxin, biophosphorous, biosulfur, mycorrhiza (Glomus mosseae) and mycorrhiza (Glomus intraradices) increased dry flower yield 27, 20, 4, 26, 30 and 28% compared to control, respectively. The highest flower and seed harvest index obtained in mycorrhiza (Glomus intraradices) and humic acid treatments, respectively. It seems that different species of mycorrhiza improved morphological characteristics and yield of Echium amoenum due to provide better conditions to absorption and transportation of nutrient to the plant. It has been reported that organic acids provided favorable conditions for plant growth and development through improvement of physical, chemical and biological properties of the soil, therefore, it can be concluded that improvement of most of studied traits in the present study were due to use of organic acids.
    Conclusion
    In general, the findings of this research showed that application of ecological inputs, while increasing yield and yield components of Iranian Ox-Tongue, can reduce dependence on chemical inputs and their environmental risks and can be used to develop sustainable agriculture and protect the health of the environment.
    Keywords: Biofertilizer, Flower Harvest Index, Health of Environment, Humic acid, Mycorrhiza, Sustainable Agriculture
  • Hamid Reza Tavakkoli Kakhki , Mehdi Nasssiri Mahallati *, Alireza Koocheki , Alireza Beheshti Pages 699-718
    Introduction
    Nitrogen fertilizers, plays an essential role in crop production and additionally its application has environmental drawbacks. So, nitrogen dynamics between cropping systems and environment is one of the most important agronomic management practices. Improving nitrogen use efficiency (NUE) is an important target in wheat cropping systems, it increases profitability through greater yields and reduction of the greenhouse gas emissions associated with the production and it could be reduce environmental hazards. There are many definitions related to NUE in the context of crop production and as well as in the literature review. One of the fundamental definition related to Moll et al (1982). According to Moll et al. (1982) definitions’ NUE as grain dry matter yield per unit of nitrogen available from the soil and fertilizer and divided it into two components 1-Nitrogen-uptake efficiency that is crop nitrogen uptake to nitrogen available and 2- Nitrogen-utilization efficiency which is grain dry matter yield to crop nitrogen uptake. Wheat is one of the most extend cultivated crops in the world. It is estimated in Iran, about 2.3 million ha of wheat cropping systems are under irrigated cultivation. The specific objectives of the present study were to 1- investigation and analysis nitrogen use efficiency variations and its components in wheat cropping systems by using simulation model.2-Determine how nitrogen use efficiency and its components (component analysis) is affected by nitrogen fertilizer levels.
    Materials and Methods
    We used CENTURY model to evaluate nitrogen use efficiency in wheat cropping systems. For this purpose 14 wheat cropping system from different locations were selected. Soil data was collected from Soil and Water Research Institute and weather data from 2000 to 2014 were obtained from Iran Meteorological Organization for 14 selected stations.The CENTURY model simulates the long-term dynamics of Carbon (C), Nitrogen (N), for different Plant-Soil Systems. The model can simulate the dynamics of agricultural crop systems. The crop systems have different plant production submodels which are linked to a common soil organic matter submodel. The soil organic matter submodel simulates the flow of C, N through plant litter and the different inorganic and organic pools in the soil. CENTURY model runs in monthly time step with calculating monthly precipitation (cm), monthly mean of minimum and maximum temperature (c°), site latitude and longitude, sand, silt and clay (%), soil bulk density (g/cm3), rooting depth (cm), C and N content of the top 20 cm of soil and management information such as planting date, first and last month of wheat growth, number and amounts of fertilization, amount of irrigation water and its schedules are required. For model validation we used three statistical measures including Normalized Root Mean Squared Error (nRMSE), Willmott (1982) index or (d index) and linear regression coefficients between actual values and predicted values.
    Results and Discussion
    Results, revealed that average nitrogen use efficiency in wheat cropping systems of Iran was 28.3 kg grain per kg of nitrogen applied. The highest and lowest mean nitrogen use efficiency were 36.02 and 21.26 kg grain per kg N that observed respectively in (Tabriz, Shiraz, Gorgan) and (Kerman, Zabol, Birjand). Regression of nitrogen use efficiency vs. yield showed that with increasing nitrogen use efficiency, yield is raised (b=0.14 kg kg-1). Separation of nitrogen use efficiency to its components indicated that on range of value (80-120 kgha-1) use of nitrogen, relative contribution of nitrogen uptake and utilization efficiency separately were 64 and 36 percent. When use of nitrogen fertilizer was increased up to value (121-160 kg ha-1) relative contribution of nitrogen uptake and nitrogen utilization was changed to 33 and 67 percent, respectively.
    Conclusion
    It seems that, when in cropping system nitrogen uptake will be dominant, agronomic management practice and in versus, if nitrogen utilization efficiency will be more important choice of superior cultivars are emphasizes the improvement of nitrogen use efficiency.
    Keywords: components analysis efficiency, correlation, utilization efficiency, uptake efficiency, simulation
  • Vahideh Safi , Ahmad Golchin , Saeid Shafiei * Pages 719-732
    Introduction
    Prediction of mineralization rate of organic carbon and nitrogen amounts of plant residues is important due to plant nutrient management, carbon dioxide production and environmental issues. Plant residues characteristics such as total nitrogen content (N), carbon: nitrogen (C/N), lignin content and particle size, Soil characteristics (texture, structure, pH and the microbial population) and Climate (temperature and moisture) are the most important factors affecting plant residues decomposition. Decomposition process of plant residues is influenced by substrate quality, decomposer community and environmental factors. Within a given climatic region, litter chemistry is the main determinant of litter decomposition. Litter decay and nutrient release are controlled by the litter quality, including the nitrogen (N) concentration of the litter, the carbon to nitrogen (C/N) ratio, as well as other chemical properties.
    Materials and methods
    To investigate the effects of size and placement depth of plant residues on organic carbon and nitrogen dynamics, a split – split plot layout based on a randomized complete block design and three replications was conducted using litter bag method. The factors were depths of incubation periods of plant residues (1, 2, 3 and 4 months), placement of plant residues (5, 15, 30 and 45 cm) and sizes of plant residues (0.2 - 0.5, 1 - 2 and 5 - 10 cm) which were located in main, sub and sub-sub plots respectively. At the end of the incubation period, the litter bags were pulled out of the pots; after the weights of the remaining plant residues in the bags were measured, the residue organic carbon was measured via the dry combustion method at 450°C for 5 h and the total nitrogen via the kjeldahl method. We analyzed the collected data during desert-lab studies by SAS/STAT software release 9.1. Statistical differences among size and placement depth of plant residues and time duration were determined using a generalized linear model (Proc GLM), P ≤ 0.05 and LSMEANS, which allows mean comparisons even when data points are missing.
    Results and discussion
    Results of data variance decomposition indicated that size and placement depth of plant residues had a significant effect on carbon and nitrogen loss at the probable level of 1℅ .The highest organic carbon and nitrogen loss were measured after four month of incubation and when the size and the depth of placement of plant residues were 0.2 - 0.5 and 30 cm, respectively. The lowest organic carbon and nitrogen loss were also obtained after the first month of incubation and when the size and the depth of placement of plant residues were 5 - 10 and 5 cm, respectively. After four months of incubation 49.73 and 54.07% of organic carbon and 34.48 and 39.78 of organic nitrogen of plant residues mineralized when the depths of placement of plant residues were 5 and 30cm respectively. Aridity, soil hilling and availability to nutrients are determining factors of the carbon cycle in the decomposition process. Conceptually and analytically advanced models from diverse studies suggest three factors affecting decomposition in arid ecosystems: quality and quantity of the organic matter under decomposition, the physical environment (including temperature, precipitation and soil type) and the nature and entity of the decomposing organs in the soil.
    Conclusion
    From the results it was concluded that when the soil moisture level is a limiting factor for plant residue mineralization, increasing the depth of placement of plant residues enhances the rate of mineralization of organic carbon by providing sufficient moisture for plant residues decomposition. The results also showed that reducing plant residues particle size with increases the surface area and plant residues contact with the soil, enhances the rate of decomposition of plant residues.
    Keywords: Incubation periods, Residue decomposition rate constant, Wheat residue
  • Behrooz Sobhani *, Yosef Hassan Zadeh Pages 733-746
    Introduction
    In many parts of the world, there is not enough precise information about suitable land for cultivation. Understanding climate and the required parameters during the growth period of crops is the mostimportant factor in the zoning Agroclimate. In Iran, lentils with acreage of 240 thousand hectares and the production of 166 thousand tons per year after the peas in second place is important. Agro-ecological zoning is one of the land evaluating method that can be used to find better lands and improve the planning and management of land resources. The purpose of this research, zoning Agroclimatic Ardabil Province for the cultivation of lentils, In order to identify the characteristics of land resources for the planning and organize and optimal land, Assessing of land suitability, in any of the zone by using AHP is Agroclimatic.
    Material and Methods
    Ardabil Province is in northwestern Iran, with an area of 17953 square kilometers, 1.09 percent of the country's total area. The present study was conducted across Ardabil Province which is located in 37° 25' and 39° 42' N latitude and between 47° 03' and 48° 55' E longitude. Data used in this research; climatic factors such as rainfall, temperature, relative humidity, sunshine duration and degree-days during the growing season are the data of 37 synoptic and meteorological and data physiographic such as elevation, slope, aspect, soil and land use map of the study area were collected from relevant organizations. By performing the necessary calculations using SPSS and EXCEL software, the database was frormed in GIS environment. Then for each of the parameters in the GIS environment with generalized point data, linear and polygon surrounding surfaces (Interpolation) were performed, as the data layers and maps. Each of the layers of the study, based on favorable climatic requirements lentils were categorized based on AHP.
    Results and Discussion
    According to the purpose of this study, the role of the main criteria such as Climate, Soil, Physiography and land use criteria selected under Options AHP were calculated and then using the weighted important factor, weight and final weight of all criteria were determined.
    Lentil planting zoning based on climatic factors: Data of climatic elements during the growing season lentils have an influential role. The sudden change of climate data is effective on crop yield. In this study, the rate of climate data based on hierarchical, weight coefficient was determined as follows: Temperature 0.382, precipitation 0.250, humidity 0.160, sunshine hours 0.101, evaporation 0.064 and wind 0.043. By overlaying maps of climatic elements, about 20.42 percent with a very suitable, 37.75 percent was suitable, 24.47 percent average and 17.34 percent of conditions are unsuitable for cultivation of lentils.
    Zoning planting lentils, based on physiographic factors: For evaluation the cultivation of lentils, map each datas, elevation, slope and aspect were prepared in GIS environment. Based on the favorable climatic lentils product to physiographic factors, weighting layers were based on AHP. Therefore, the height by a factor of 0.614, slope 0.268 and slope were determined 0.117. By combining maps of physiographic province, 22.68 percent has a very suitable, 21.11 percent sutitable, 17.33 percent average and 38.86 percent conditions are unsuitable for cultivation of lentils.
    Zoning lentil cultivation, on the basis of physiographic and climatic elements: By combining all the maps of climatic and physiographic factors that were prepared based on hierarchical method weighting coefficient, the final zoning map Agroclimate lentil cultivation in this province was prepared. Based on the final map, in Ardebil province about 17% very suitable, 32% was suitable, 27% moderately and 24% had poor conditions for the cultivation of lentils.
    Conclusion
    This study aimed to Agroclimateland zoning for planning agriculture in the province of Ardabil. Based on the favorable climate condition for lentil crop, land evaluation of each data was done for production of lentils. So the the main criteria including; climate 0.565 factor, physiographic by a factor of 0.262, soil 0.188 and land the highest weight by a factor of 0.055 respectively has an effective role in the lentils, as well as minimum temperature during the growing season and maximum temperatures and low rainfall (during seed germination and flowering) altitude and the high slope is the limiting factor for the cultivation of lentils in the province.
    Keywords: AHP, Ardabil Prvince, Climate, GIS, Lentil Crop, Physiography
  • Amir Reza Sadeghi Bakhtoori *, Bahman Paseban Eslam , Nastaran Hajizadeh Asl Pages 747-763
    Introduction
    Water stress is one of the most important environmental stresses that affect the germination, growth and yield of plants. Seed priming is a technology that positively influences seedling establishment in many crops and may improve field performance under adverse environmental conditions. Seeds can be primed using different media such as tap water (hydro-priming), low water potential solutions (osmo-priming) such as polyethylene glycol or salt solutions, solid matrix (matri-priming), and plant growth regulators (hormonal priming). Nitroauxin and auxin are the rich source of macro-nutrients, micro-nutrients, vitamins, enzymes and hormones of plant growth promoters. Therefore, the use of these media in sustainable agriculture causes the rapid growth of oil seed plants. Limited information is available about the response of sunflower under water deficiency conditions in priming, so the aim of this research was to study the growth and yield of these species under these conditions.
    Materials and Methods
    An experiment was conducted in 2014 at the field research station of the Faculty of Agriculture of Azerbaijan Shahid Madani University, Iran. The experiment was laid out as a randomized complete block design arranged in a factorial with three replications. Priming factor included (water treatment and nitro auxin, water and auxin, hydro-priming and control (without priming)) and factor water stress include (stress during stem stage, stress during grain filling stage and control (normal)).The seed priming 48h before sowing were treated with the water and nitro auxin, water and auxin and hydro-priming for 16h, after priming, seeds are air-dried back near to the original weight. Seedlings planted by hand on 2 may 2014 by density of 38000 plants ha-1 (60×30 cm). Weeds were controlled by hand during crop growth and development as required. At maturity, five plants randomly were harvested from each plot and plant growth rate, head growth rate, head diameter, No. of seed per head, 1000 seed weight, seed yield per plant and kernel to grain ratio, husk to grain ratio and percentage of unfilled seeds were recorded. The data were analyzed by SPSS 16 software. The means were compared using the Duncan multiple range test at p ≤0.05. Excel software was used to draw figures.
    Results and Discussion
    Analyses of variance of the data showed that all traits were affected by water stress and seed priming main effects. Priming of seeds increased significantly the absolute growth rate, head diameter, grain number, 1000 seeds weight, grain yield and kernel to grain ratio and husk to grain ratio was reducing the percentage of unfilled seeds per head. Water stress also reduces all traits except unfilled seeds per head, which enhances it. Water stress at the grain filling stage was causing the most reduction of grain yield per unit area.
    The increase in growth and yield of sunflower with seed priming treated nitro auxin and auxin could be due to the fact that by promoting germination and providing more uptakes of phosphorus and nitrogen. Reduction in the growth and yield under water stress could be the result of a preferential allocation of biomass production to the roots or a reduction in chlorophyll content and, consequently, photosynthesis efficiency. Seed yield decreased on account of water deficit stress. Decrease in seed weight and increase in unfilled seeds were the main reasons for decreasing in seed yield. Decrease in seed yield due to decrease in yield components, especially seed weight has been reported by other researchers previously. The increase in Percentage of unfilled Seeds under water stress could be due to the fact that water stress effect on available assimilates during seed filling stage and decreases sink capacity and leads to unfilled seeds and low seed weight.
    Conclusion
    In conclusion, this study showed that application of seed priming play useful role in improving the growth, yield and performance components of sunflower, and also the seed priming with auxin and nitro auxin, were better than seed hydro-priming, this can be related to the chemical properties of these compounds. The results of this study indicate that pre-treatment of seeds are effective in increasing yield and yield components of sunflower seeds in order to avoid adverse effects of water stress.
    Keywords: Seed priming, Seed yield, Water stress
  • Alireza Pirzad *, Naser Jafarzadeh , Hashem Hadi , Ramin Maleki Pages 765-774
    Introduction
    Castor bean, as an important commercial oil-based by products are used in the manufacture of several commercially important commodities like surfactants, coatings, greases, pharmaceuticals, cosmetics, polyesters, polymers. Castor bean is a non-edible oilseed crop which produces an oil rich in Ricinoleic acid, commonly over 80%. The seeds of castor consist of 40-60% by weight of the most useful natural plant oil. Interactive effects among species on inter-species populations are called interference. Interference is one of the main issues on the eco-physiology of plant populations where weeds impose negative effects by approaching the plant to compete in light, water and nutrient elements availability and results in reduced growth and yield. Various reasons have been attributed for the low productivity of crops, among them weed competition is the most important. Redroot pigweed belongs to the Amaranthaceae family, as an important competitor to slow growth of the castor bean plant, can deprive it from nutrients. The purpose of this research was determining the effects of redroot pigweed plant density interference on the yield of oil and fatty acids composition of castor bean plant to increase quantity and quality of oil.
    Materials and Methods
    To evaluate the effects of Pigweed interference on yield, oil content and fatty acid composition of castor oil plant, a factorial experiment was conducted based on randomized complete block design with three replications at the Center for Agricultural Research in West Azerbaijan (Urmia) (Saatlu station: 37°44´18״ N Latitude and 45° 10´ 53״ E Longitude, at 1338 m above sea level) with silty-sandy soils. The first factor included Castor plant densities (3, 4, 5 and 6 plants per square meter) and the second was Amaranth densities (zero, 5, 10 and 15 plants per square meter). Castor seeds cv. Mobarakeh were planted with red root pigweed simultaneously on 14 June 2013. After Soxhlet extraction, fatty acid analysis was performed by Gas Chromatography. Data were analyzed with SAS 9. 1 software.
    Result and Discussion
    The results showed the significant effects of castor and amaranth densities, and their interaction effects on the castor oil yield, but only significant effect of amaranth density on the fatty acid composition. According to the results, increasing Amaranth density caused to reduction of 20-38% in castor grain yield, 39% in oil yield compared to pure cultures (without weed). Due to the unique characteristics of ricinoleic acid, it was reduced 19% by increasing pigweed density, but the palmitic acid (74%) and stearic acid (108%), linoleic acid (12%) and Oleic acid (64%) were increased compared with pure cultures (weed free). The results of the survey indicated that the pigweed at densities of 10 and 15 plants per square meter is one of the most important factors affecting yield, oil content and fatty acid composition. In this experiment, Amaranth weed caused to significant reduction of the yield of castor grain, oil and major fatty acids. In this regard, pigweed control at the beginning of the growing season will be effective to reduce seed production, in order to reducing crop yield loss and reduce the scope of its release in the next years. In general, despite the importance of castor plant there has been limited research work carried out on the crop in Iran to increase the crop competitive ability. In this present study, the oil content, oil yield and fatty acids composition of Iranian castor bean oil have been outlined. The results of this experiment showed that changes in oil content and fatty acid composition is depending on environmental conditions such as competition with weed and the Pigweed is a competitive weed which significantly reduces the quantitative (seed and oil) and qualitative (oil composition) yield.
    Conclusion
    Increasing pigweed density decrease grain yield, oil yield and fatty acids composition of castor bean. The amount of this reduction was related to pigweed density. On the other hand, 6 plants/m2 of Castor bean can be recommended for reducing pigweed damage in Castor bean.
    Keywords: Interference, Oil yield, Oleicacid, Palmitic acid, Ricinoleic acid
  • Zhaleh Zarei , Hassan Heidari *, Iraj Nosratti , Mahmood Khoramivafa Pages 775-787
    Introduction
    Sunflower (Helianthus annuus L.) is one of the plants cultivated for oil or seed. Sunflower oil contains many useful fatty acids. One of methods to increase plant yield and decrease input consumption is transplanting. Transplanting can increase seed yield components such as head number per plant, seed number per head, 1000-seed weight. Transplanting increased seed yield and quality compared to direct seeding due to no frost at the beginning of growth season and increasing flowering length. By delaying transplanting, seed germination or transplant establishment is reduced. Time interval from seeding till beginning and terminating flowering length can be reduced by delaying at seeding, but by transplanting flowering duration length increases. Drought losses crop productions especially at plant critical growth periods such as seed filling stage. In arid and semi-arid areas like Iran, water shortage leads farmers to plant low- water crops. By transplanting of sunflower, water can be saved, because seedling can be grown by a little water in controlled condition. In addition, some plant growth stages coincide with cool and rainy weather in spring. Many farmers use transplanting for warm season crops, but transplanting of sunflower has not been well studied. This research was aimed to assess sunflower transplanting under common sowing date and early sowing in Kermanshah climate condition.
    Material and Methods
    An experiment was conducted at greenhouse and research field, campus of agriculture and natural resources, Razi University in 2015 and 2016. In the first year, factors included three planting methods (direct seeding, 4-week transplanting and 6-week transplanting) and sowing date (early sowing, common date sowing). In the second year, treatments included 4- week transplanting at early sowing (superior treatment in the first year) and direct seeding (control). At harvesting stage, four plants per plot were selected and traits such as plant height, stem height, stem diameter, leaf number, internode length, leaf width, leaf length, leaf fresh weight, stem fresh weight, seedling fresh weight, leaf dry weight, stem dry weight and biomass were measured. Leaf greenness was measured by SPAD device and stomatal conductance was measured by porometer device. Leaf area was determined by digimizer software. Leaf relative water content, chlorophyll a and b, seed yield and yield components also were measured. Data were analyzed by SAS software. Mean were compared using LSD test.
    Results and Discussion
    Analysis of variance of 2015 data, showed that planting method and planting date had significant effect on plant height, leaf relative water content, dry matter and leaf area. 4-week transplant at early planting date had the highest dry matter production and leaf area selected for the second year. It seems that by delaying in transplanting, sunflower plant become more sensitive to cold air and low temperature damages plants, so lower dry matter production was produced. Results of the second year showed that transplanting increased green leaf number, leaf area, chlorophyll a, plant fresh weight, plant dry weight, leaf to stem ratio, stem length, plant height, seed number per head, dehulled seed weight, hull weight, seed yield and 100-seed weight. It seems in transplanting, maximum stem length, plant height, green leaf number and leaf area was occurred when sunlight was maximum, so plant had higher radiation use efficiency and dry matter production. In addition, transplanting had higher seed yield than seeding probably due to weed suppression, rapid establishment, shorter growth duration and faster flowering. Transplanting increased seed yield and weight due to lack of coincidence of plant critical stages to adverse environmental conditions, suitable plant cover, prolonging the grain filling period and store assimilates in grain.
    Conclusion
    In conclusion, it is suggested to plant 4-week sunflower transplant at early date in Kermanshah climate condition.
    Keywords: Direct seeding, Dry matter, Planting method, Seed yield, Yield components
  • Sahar Afzaliharsini *, M.Sadegh Taghizadeh , Ali Behpoori , Farzane Faramarzi Pages 789-803
    Introduction
    Use of chemical herbicides has been very effective for weeds control mainly for reducing yield losses and reduction of weed populations, but the frequently use of herbicides as the only weed management tool is seriously being questioned because of herbicide costs, resistance of weed populations to one or multi herbicides and environmental pollution. Reduce the use of chemical herbicides is one of the sustainable agriculture goals and several alternatives with this purpose have been evaluated, recently. Therefore, diversification of cropping systems by intercropping different species of crops has been proposed as a solution for reducing the use of herbicides in modern agriculture.The main objective of current field experiment was to evaluate the growth and micro nutrients content of weeds and crop yield in wheat cultivar intercropping systems.
    Materials and methods
    In order to investigate wheat-weed competition relationships and crop yield under intercropping and sole cropping of wheat cultivars, an experiment was conducted at Darab faculty of Agriculture and Natural Resources, Shiraz University, during the growing seasons 2013-2014. The experiment carried out using randomized complete block design with eight treatments and three replications. Wheat cultivars and genotypes were planted in four row intercropping systems and four sole cropping systems, including I1: intercropping of shirudi + 91-11, I2: intercropping of shirudi + 91-15, I3: intercropping of 91-11 + 91-15, I4: intercropping of shirudi + 91-11 + 91-15, S1: shirudi sole cropping, S2: 91-11 sole cropping, S3: 91-15 sole cropping and S4: F2 sole cropping. Different weed species were recorded in field experiment, but total weed density and total weed dry matter were determined for each experimental plot. Weeds density were determined from each experimental plot by using a quadrat of 1 × 1 m-2 randomly. Then all weeds in each quadrat were harvested and transformed to laboratory for determining their biomass and micronutrients (Fe, Zn, Cu, and Mn) content. At harvest time, all crops harvested in each plot, then crop yield was determined.
    Result and Discussion
    Results showed that genotype mixtures had a significant effect to reduce the density, biomass and micronutrients content of weeds. The highest and lowest weed density and biomass were observed in sole cropping and intercropping systems, respectively. Intercropping systems of cultivars reduced weed population and their dry matter more than sole cropping systems. Shirudi sole cropping (39.33 plant. m-2) showed the highest weed density and the highest weed dry matter was observed in 91-11 sole cropping (130 g.m-2) and shirudi sole cropping (121.3 g.m-2). The highest and the lowest micronutrients content of weeds including Iron (Fe), Zinc (Zn), Cooper (Cu) and Manganese (Mn) were observed in sole cropping and intercropping systems, respectively. The highest Fe, Zn, Cu and Mn content of weeds were observed in 91-11 and shirud sole cropping (225 and 245.6 mg.kg-1, respectively), shirudi sole cropping (27.5 mg.kg-1), 91-15 sole cropping (21.23 mg.kg-1) and shirudi sole cropping (63.85 mg.kg-1), respectively. The highest and lowest crop yield were observed in shirudi + 91-15 intercropping (5.40 ton.ha-1) and 91-15 sole cropping (2.70 ton.ha-1), respectively. In overall weeds micronutrients content and weed growth in intercropping systems decreased significantly in comparison to sole cropping systems. The results of this experiment showed that row intercropping of wheat cultivars can reduce the weeds ability for use of environmental resources, therefore crop can utilize resources more efficiency and increase its yield.
    Conclusion
    The results showed that wheat cultivars intercropping method limits environmental resources for weeds growth and this have implication for non-chemical management of weeds and increasing crop yield in ecological approach in agro-ecosystems. Thus, wheat cultivar intercropping systems can modify weed infestation in cropping systems. The results of this study suggest that row- intercropping system of wheat cultivars have potential to produce higher yield and less vulnerable to weed infestation than their sole cropping system, because they can provide high genetic diversity.
    Keywords: Agroecosystem, Density, Enviromental resources, Monoculture, Non-chemical management
  • Soheila Ghasemi Maham *, Seyfollah Fallah , Amir Dadrasi Pages 805-822
    Introduction
    In the cultivation of medicinal plants, employing practices that can increase the essential materials is of necessary issues. Intercropping can improve the ecological diversity and stability in agro-ecosystems, increase the yield and reduce the use of chemical compounds. In addition, application of integrated fertilizers on agricultural soils may affect ecosystem sustainability, directly or indirectly, through changing the amount of chemical fertilizers application. Integrated fertilizers not only increase the yield, but also prevent environmental pollution. Accurate assessment of plant growth changes in various agricultural land management cannot be achieved by measuring an individual simple parameter. For this reason, simultaneous determination of several growth indicators can be a suitable method for monitoring the changes of plant growth in different conditions. The use of multivariate analysis is a beneficial approach in agronomic studies, since the method can easily assess the measured indices and more clearly interpret the results. Principal Components Analysis (PCA) or Factor Analysis (FA) are among of multivariate analysis methods in which reducing the number of primary studied variables is their initial aim. The purpose of this research was to evaluate the changes of psyllium growth indices in different fertilizer treatments and different combinations of intercropping using multivariate analysis and selection of the most sensitive growth indicator.
    Materials and Methods
    In order to evaluate the effects of different fertilizer types and intercropping ratios on the quantitative and qualitative yield of psyllium, the study was setup as 3×4 full factorial arrangement based on a randomized complete block design with three replications for each treatment over a period of 120 days. The treatments were intercropping ratio (monoculture of psyllium, trigonella: psyllium (2:1), fenugreek: psyllium (1:1), fenugreek: psyllium (1:2)) as the main plot factors and fertilizer types (cow manure, integrated fertilizer and chemical fertilizer) as the sub-plot factors. In intercropping treatments, the amount of fertilizer consumption corresponded to their intercropping ratio. Finally, 20 plants were randomly collected from each plot and were transferred to the laboratory. Data obtained from the study were analyzed using multivariate analysis (Factor Analysis, FA).
    Results and Discussion
    Extracted factors were rotated by Quartimax rotation to set most of the factor loadings on the first factor. Factor analysis led to the selection of four factors with eigenvalue greater than 1. The eigenvalue of fifth factor was 0.981, so it was not considered in the analysis and interpretation of data. The first, second, third and fourth factors were accounted for 31.1, 22, 18.3 and 8.3% of the variability of the data, respectively. These three factors explained 79.7% of the original variability, totally (i.e., variance). Consequently, four factors were retained to represent the original variability of the dataset. The first factor had 5 highly weighted variables with positive loadings for mucilage yield, the percentage of mucilage and inflation factor and negative loadings for other variables. The first factor, which included most of the qualitative and quantitative indicators as input variables, clearly separated fertilizer treatments. Number of branches, during spike and the weight of one thousand seeds loaded heavily on the second factor with a positive loading for all properties. The second factor noticeably discriminated intercropping treatments. The effect of fertilizer treatments depended extremely on intercropping ratio, due to positive interaction between fertilizer type and leguminous symbiosis. However, the positive impact of fertilizer treatments was only related to appropriate intercropping ratio (1:2), probably due to suitable space for psyllium growth.
    Conclusion
    Factor analysis was used successfully in discriminating the effects of fertilizer type and intercropping on psyllium growth indicators. As a result, psyllium qualitative and quantitative properties were positively affected by the first and second factors. The first and second factors were clearly affected by fertilizer type and intercropping ratio, respectively. Therefore, these factors can be used for improving psyllium growth and increasing its quality. Moreover, application of integrated fertilizer not only increase intercropping efficiency, but also reduce environmental pollution.
    Keywords: Integrated manure, Leguminous symbiosis, Medicinal plant, Multivariate analysis
  • Somayeh Soheili Movahhed , Saead Khomari *, Parisa Sheikhzadeh , Bahram Alizadeh Pages 823-840
    Introduction
    The stable nature of plants constantly makes them to expose to a variety of environmental conditions that are often stressful and undesirable. Drought or water deficit stress is the most important environmental factor which has severe negative impacts on crops yield, especially when the water deficit stress occurs in the flowering stage, it will affect the crop production. The nutritional imbalance in plants is one of the effects of drought stress. Proper plants nutrition under stress conditions may partially help plants against various stresses. The growth and yield of plants under stress conditions can be improved by spraying foliar micro nutrients. Boron is essential for protein synthesis, seed and cell wall formation, pollen germination and pollen tube growth. Zinc application has a significant impact on basic plant processes such as metabolism and nitrogen uptake, improving the quality of protein structure, photosynthesis, resistance to biotic and abiotic stresses in plants and their protection against oxidative damage. The aim of this study was to investigate the effects of foliar spray of boron and zinc on yield and yield components of spring safflower (cv. Mahalli-e Esfahan) under late-season water deficit in Ardabil province.
    Materials and Methods
    The field experiment was conducted at the Research Farm of the University of Mohaghegh Ardabili, Ardabil, Iran in 2014 and 2015. The experimental arrangement was split factorial based on a randomized complete block design with three replications. The main-plot factor consisted of three levels of water treatments (S1: full irrigation until end of season, S2: without irrigation in flowering, S3: without irrigation in seed filling) and the sub-plot factor included factorial combination of Boron (B1: 0, B2: 350, B3: 700 ppm) and Zinc (Z1: 0, Z2: 1000, Z3: 2000 ppm). B was added as Boric Acid (H3BO3) and Zn as Zinc Sulfate (ZnSO4). The treatments were applied during anthesis (when 50% of the plants were at anthesis stage) as foliar applications (Dordas et al., 2007). All other agricultural practices (weeds control and irrigation), were performed when they were required and as recommended for safflower production. The measured traits included plant height, fertile and infertile capitoles per plant, grain number per capitole and plant, unfilled grain percentage, 1000-kernel weight, grain yield, biological yield and harvest index. Analyses of variance and comparison of means at P≤0.05 were carried out, using SAS 9.1 software. The means were compared using LSD test.
    Results and Discussion
    Combined analysis of variance of the data showed that year was significant for all the traits (except infertile capitoles per plant). During the second year, there was no significant difference among all the treatments due to heavy rainfalls. The results of the mean comparison of data showed that all parameters were superior in the second year compared to the first year. Also Seed number per plant, 1000-kernel weight, seed yield and biological yield were significantly affected by drought stress. The results demonstrated that water deficit stress at flowering and seed filling stages significantly decreased grain yield compared to full irrigation (7.94% at flowering and 8.25% at seed filling). The interaction effect of Boron×Zinc was significant in all considered characteristics (except plant height and biological yield). The treatments of B3Z2, B2Zn2 and B1Zn3 had the greatest increase of these parameters in comparison with B1Z1 (control). The treatment of B3Z2 had the greatest increase (47.66%) of grain yield in comparison with B1Z1 (control). Under stress conditions during flowering and grain filling stages, number of infertile capitoles per plant, 1000-grain weight and grain hollowness were considerably improved through micronutrients foliar application. Boron and Zinc foliar application significantly improved most traits under water stress levels.
    Acknowledgments
    We would like to thank from the Faculty of Agriculture, Mohaghegh Ardabili University, for supporting this study.
    Keywords: Flowering stage, Drought stress, Micronutrients, Resistance to drought
  • Azam Gideski , Reza Baradaran * Pages 841-851
    Introduction
    Drought stress is one of the most important environmental abiotic stress causes a decrease in crop yield, especially in arid and semi-arid regions of the world. Millet is a traditional cereal cultivating in arid and semi- arid zones, tolerant to drought and salinity. The application of water stress, especially in the millet development stages (from stem elongation to later), reduced plant height and resulted in decreased production and storage of photosynthetic materials (Khazaee et al., 2005). In arid and semi-arid areas, not only water scarcity but also absorbable nutrient elements deficiency in soil always restricts plant growth. Micronutrients are essential for natural growth of plants and in addition to their cooperation in the structure of some organelles they are involved in many chemical reactions. The shortage of these elements may sometimes act as limiting factor of absorption of other nutrient elements and growth.spraying Manganese and Zn combining with the other spray treatments resulted in the highest growth parameters of the Setaria italica. The aim of this experiment is to investigate the effects of drought stress and spraying manganese and zinc micronutrients and their interactions on morphological traits, harvest index, seed per panicle and seed yield of common millet.
    Material and Methods
    To investigate the effects of different irrigation intervals and foliar application of micronutrients on Panicum miliaceum, an experiment was conducted as split plot arrangement based on randomized complete block design with three replications in Sarbisheh agricultural research farm in south Khorasan province on 2012. Each replication included three main plot factors based on irrigation levels (7, 14 and 21 days irrigation intervals). Each main plot had four sub plot factors which treatment of foliar application with micronutrients were conducted on them (foliar application treatment with manganese, zinc, manganese and zinc without foliar application). Plant height, the number of leaves per plant, flag leaf area, peduncle length, panicle length, harvest index of seed in the panicle and seed yield was measured.
    Results and Discussion
    Drought stress cause significant differences on plant height, the number of leaves per plant, flag leaf area and peduncle length at 5% significance level and on panicle length and seed yield at 1% significance level. Drought stress decreases morphological traits by reducing photosynthesis, growth period length and material partitioning to organs. The effect of foliar application on plant height, panicle length, peduncle length and the number of leaves in plant and seed yield was significant at 0.01 probability. Foliar application had not significant effect on flag leaf area. Drought stress caused a significant difference at significance level of 5% on harvest index. The highest harvest index (53/46) was related to 7-day irrigation interval treatment. In the absence of sufficient water, material partitioning to reproductive organs and especially seed would be decreased which causes the reduction of harvest index. The effect of Zinc and Manganese foliar application on harvest index was significant at the significance level of 1%. The highest harvest index with 14.1% increase in compare to the control treatment was related to Zinc and Manganese foliar application treatment. Increasing morphological traits produced seed with higher power and finally harvest index of seed in panicle increased.
    Conclusion
    Considering achieved results, the decrease of irrigation interval can increase the photosynthetic surface and consequently seed yield. Micronutrients foliar application also causes an increase in morphological traits and seed yield. Spraying micronutrients increased seed weight, number of seed per panicle and seed yield. The interaction of irrigation interval and micronutrients foliar application was significant too. The highest seed yield was related to 7-day irrigation interval and manganese and zinc foliar application with 222.6 grams per square meter.
    Keywords: Common millet, Irrigation interval, Manganese, Morphological traits, Seed yield, Zinc
  • Reza Arefi *, Afshin Soltani , Hosein Ajamnorozei Pages 853-873
    Introduction
    Energy is of particular important in agricultural inputs due to the increasing rate of consumption, fossil fuels adverse impacts on the environment and limited sources. Due to the growing demand of energy, increasing world population, increasing food consumption per capita and improvement of life quality, the energy, the way it consumes and increasing its efficiency and optimization are very important. Moayedi et al (1388) indicated that the highest energy consumption of the first year of saffron cultivation was related to manure application with a 16.91% of the total energy consumption and in the second to fifth to urea fertilizer with a 67/37% of the total energy consumption. Similarly, energy production to consumption ratio over a period of five years of saffron cultivation was estimated to be 41/0. Ahamadi & Aghaalikhani, (2013) reviewed the energy consumption of cotton in the Golestan province. They considered the share of energy use in cotton in Golestan province, the share of energy consumption in tractor fuel inputs and fuel pump to be 24%, 30% respectively, and 54% of the energy was related to diesel fuel. Fertilizers had 24% and chemicals had 13% of energy consumption, and the total energy input for the production of cotton in Alborz Province was announced to be 31 GJ per hectare. Considering the energy crisis in the world, exploring the demand and consumption rate of energy and finding solutions to reduce the consumption is of researcher’s priority globally. Considering the privileged position of cotton production in the world and Golestan province of Iran, estimation of energy input and, efficiency are among the main research areas leading to fruitful solutions of optimizing energy consumption of the product.
    Materials and Methods
    A hundred of cotton fields around the Aliabad and AqQala cities in Golestan province were selected during two sowing years of 2014 and 2015. These farms were selected in such a way a number of farmers can be included. Important dates of different operations and events were observed during the growing seasons in selected fields. The data of typical production methods and cultivation practices were collected in last year including the use of equipment and fuel, application of fertilizers and pesticides and so on. Accordingly, all agricultural practices were divided into eight categories, including land preparation, planting, fertilizer application , plant protection, weed control, irrigation, harvesting and transportation to factory or crop delivery, primarily. Then, the different amounts of input use and more comprehensive information were collected and recorded at every single stage from planting to harvesting.
    Results and Discussion
    The results showed that the highest energy consumption was related to irrigation with 41% of the total energy and fertilizer application and land preparation were in the next positions. Labor force energy was calculated to be 2262 MJ.ha-1 related to harvesting, irrigation, cultivation, and crust-breaking. 61% of the total energy (10217 MJ.Ha-1) was used indirectly for the manufacturing, repair and maintenance of equipment and machinery, and production of seed, nitrogen fertilizer, phosphate fertilizer, potassium fertilizer, organic fertilizer, t insecticides, herbicides and industrial fungicides. Nitrogen fertilizer production consumed 30 percent of indirect energy sources, the highest share, while 39 percent of the total energy consumption was related to direct energy through the use of human resources and fuel consumption. Average power ratio of total farms was equal to 92.5. The results of levels of total energy input to fields showed that the minimum and maximum energy inputs were 15614 and 43321 MJ per hectare, respectively.
    Conclusion
    The results of this study showed that most of the direct energy (labor and fuel) consumption for cotton production is related to fuel with 86 % of the total energy mostly used in irrigation practices. Several factors such as soil texture, farm leveling, plant's feeding and protection, equipment and types of pumps, irrigation equipment maintenance in a timely manner, weather conditions, the amount of water available and most importantly short-term and long-term management are among areas which can reduce fuel and energy consumption of irrigation practices in the cotton production farms of Golestan province.
    Keywords: Cotton, Fuel, Input Energy, Output energy
  • Arash Mohammadzadeh , Abdolmajid Mahdavi Damghani *, Javad Vafabakhsh , Reza Deihimfard Pages 875-895
    Introduction
    Agriculture development heavily relies on chemical inputs such as synthetic fertilizers, pesticides, fossil fuels and other energy-intensive inputs. This development is having a serious impact on public health and the environment. Therefore, efficient use of resources is a primary and most vital implications for sustainable agriculture development. Sustainability indices are quantitative values that can be used to evaluate the efficiency and quality of agroecosystems and are useful tools for making suitable decisions in its management. These including energy flow indices, global warming potential (GWP), economic indices, environmental impact quotient (EIQ) of pesticides, efficiency of land, water and fertilizers use and etc. Alfalfa and corn silage as the main source of feed for livestock, have a notable area in the cropping pattern of Maragheh-Bonab plain. Therefore, evaluation of sustainability for these crops will help the sustainable management of agroecosystems in the study area. The present study was conducted to: (a) determine energy efficiency and global warming potential; (b) determine the environmental impacts of pesticides; (c) assess input use efficiency and; (d) economic analysis of alfalfa and corn silage production systems in East Azerbaijan province of Iran.
    Materials and Methods
    In the present study, the sustainability of alfalfa and corn silage production systems lies in the Maragheh-Bonab plain in southern East Azerbaijan province in northwestern Iran were evaluated using quantitative indices such as energy efficiency and productivity, greenhouse gas (GHG) emission; economic indicators; pesticide risk (field environmental impact—FEIQ); tillage impact (TI); fertilizer, labour, land and water use efficiency, and the eco-efficiency index. For this purpose, data was collected from 110 farmers by survey to determine crop production in the region. Secondary data including climate characteristics and products sale price was obtained from previous studies and organizations such as the Agricultural Ministry of Iran.
    Results and Discussion
    The results showed that the values of input energy, output energy and net energy in alfalfa production system (48151, 432920 and 384768 Mj.ha-1, respectively) were higher than corn silage production system (35557, 217350 and 181792 Mj.ha-1, respectively). Also, it was observed that the values of energy use efficiency and specific energy of alfalfa (9 and 15.8 MJ.kg−1, respectively) were higher than that of corn silage (6.1 and 4.1 MJ.kg−1, respectively). In terms of economic indices, despite of lower total cost of production in corn silage (1089 $.ha-1), the highest values of gross production value (6447 $.ha-1) and net return (4193 $.ha-1) were related to alfalfa production system. In terms of GWP and EIQ, alfalfa production had the higher values with compared to corn silage production. However, eco-efficiency (ratio of economic value to the environmental impact) values based on of GWP and EIQ was significantly higher for alfalfa (1.75 $.kg -1 CO2eq-1 and 35.3 $.EIQ-1) than corn silage (1.5 $.kg-1 CO2eq-1 and 26 $.EIQ-1). Land production efficiency, economic land production efficiency, irrigation water productivity, economic irrigation water productivity, nitrogen use efficiency, phosphorous use efficiency and potassium use efficiency were 140 kg.ha-1.day-1, 21.5 $.ha-1.day-1, 4.1 kg.m-3, 0.63 $.m-3, 335 kg.kg-1, 1191 kg.kg-1 and 1826 kg.kg-1 in alfalfa production system and 583 kg.ha-1.day-1, 22.9 $.ha-1.day-1, 8 kg.m-3, 0.31 $.m-3, 656 kg.kg-1, 3553 kg.kg-1 and 65525 kg.kg-1 in corn silage production system, respectively.
    Conclusion
    It can be concluded that environmental impacts of pesticides and global warming effect per area in alfalfa production system were higher than corn silage production system. However, in terms of economic indices and energy use efficiency, alfalfa production system was superior to corn silage production system.
    Keywords: : Energy efficiency, Fertilizer use efficiency, Global warming, Pesticides, Water productivity
  • Saeedeh Rahimzadeh , Alireza Pirzad * Pages 897-911
    Introduction
    The relationship between arbuscular mycorrhizal fungi (AMF) and their associated bacteria has great importance for sustainable agriculture especially in the case of highly mycorrhizal plants such as flax seed. Bio-fertilizers use in sustainable agricultural systems is important in production and enables plants to absorb more water from soil and improves plant nutrient uptake and photosynthesis. The alleviating effect of the AMF symbiosis in response to drought generally relies on the uptake and transport of water and on an improved uptake of nutrients. The cooperation of bacteria and mycorrhizal is probably due to specific attributes of micro-organisms that make the mother plants more tolerant to drought stress .The interacting effects of mycorrhizal colonization and phosphate solubilizing bacterial (PSB) inoculation on plant vegetative growth and crop yield have been studied previously. But, the impact of these above micro-organisms on the plant reproduction and the actual (quality) crop yield has received much less attention. Thus the main aim of this study was to evaluate the effects of AMF species, PSB and their interactions on the quality of harvested flax seeds.
    Materials and Methods
    A 2-year field experiment was conducted at the Urmia University, Urmia city, located at North-West of Iran during the years 2014 and 2015. The experimental design was factorial (three factors) based on a randomized complete block with three replications. The treatments were included two AMF species (Funneliformis mosseae, Rhizophagus intraradices and non-mycorrhizal control), PSB (Pseudomonas putida P13 and non-inoculated control) and three irrigation regimes (irrigation after 60, 120 and 180 mm of evaporation from Class A pan). Seeds were sown into a loamy soil at a depth of 2 cm in plots. Mycorrhizal inoculum was placed in the planting rows below the seeds. For bacterial treatments, the seeds were inoculated with bacterial suspension of Pseudomonas putida strain P13 before being immediately planted. At the end of the growing season, when the plants had produced mature seeds, samples were taken. Seed factors included germination percentage, nutrient percentage (N, P and K), mucilage percent, swelling factor, electrical conductivity and potassium leakage (parameters as a result of damage to seed cell membranes) were measured. Finally, data was analyzed using SAS 9.1 and means were compared by Student Newman Keul’s test at 5% level of probability.
    Results and Discussion
    Combined ANOVA of 2-yr data showed a significant interaction effect of irrigation regimes multiply by bacteria and mycorrhiza on the final germination percent, mucilage content, swelling factor, swelling rate per gram mucilage, seed nutrients (nitrogen, phosphorus and potassium), and potassium leakage, and significant interaction of year multiply by irrigation regimes and mycorrhiza on the electrical conductivity in flax seeds. Results indicated that with increasing irrigation interval from 60 to 120 mm of evaporation in control (non-inoculated) plants, phosphorus percent, potassium percent, mucilage percent, swelling factor and swelling rate per gram mucilage, and potassium leakage were in high level. These above traits decreased with increasing in severe stress up to 180 mm of evaporation. With increasing drought stress in flax plants (from irrigation after 60 to 180 mm evaporation), protein content and final germination percentage and rate of harvested seeds were decreased. Mycorrhizal and bacterial inoculation of flax plants, especially dual inoculation, compensated a part of drought-induced seed protein reduction. In all irrigation regimes, the highest percentage of phosphorus, potassium, mucilage and swelling factor were observed in dual inoculated plants due to synergistic effect of mycorrhiza and PSB. This synergistic effect led to reducing cell membrane damages that indicated the vigorous seeds. But a downward trend of seeds germination percentage harvested from inoculated plants, related to higher mucilage volume and its negative correlation with seed germination.
    Conclusion
    A mixture of AMF and bacteria improved the results more than they were for the non-inoculated control plants. The development of multi-functional microbial inoculants seems to be a promising method to increase the positive effects of micro-organisms. In this study, the participation of micro-organisms contributed to a higher quality and vigor of flax seeds. Assessment the effects of plant-beneficial micro-organisms (Pseudomonas putida and two mycorrhizal species, alone or/and in combination) on the quality of flax seeds obtained from plants grown in the field, showed the beneficiary of dual colonization.
    Keywords: Drought stress, Mucilage, Mycorrhizal fungi, Pseudomonas, Seed germination
  • Sara Asadi , Mohammad Banayan *, Mohsen Jahan , Alireza Faridhosseini Pages 913-924
    Introduction
    The role of leaf area index (LAI) in terrestrial ecosystems is undeniable. LAI affects the amount of carbon, water and energy metabolism. Also, many agronomic, environmental and meteorological applications require information on the status of LAI. The time series of the spectral indices obtained from the remote sensing indicates its usefulness in detecting regional-scale LAI changes. So, the desire for the development of models for estimating LAI was increased with using satellite images. Vegetation Indices (VIs), especially the Normalized Difference Vegetation Index (NDVI) and Ratio Vegetation Index (RVI), are most widely used. According to the different sensitivity of VIs to the value of LAI and vegetation characteristics, in this study, we tried to determine an algorithm with a higher accuracy to estimate the LAI of wheat using more variables (VIs).
    Material and Methods
    In this study, regarding the wheat growth period in Astan Quds Razavi (AQR) farms, the Landsat 8 satellite images were used from November 22, 2014 to June 20, 2015. LAI was measured simultaneously with passing of Landsat 8 (16-day intervals) from AQR Fields of Mashhad (in five dates from 17 farms) during wheat growing season in 2014-2015.
    After pre-processing of satellite images, VIs including the Difference Vegetation Index (DVI), NDVI, RVI, Transformed Difference Vegetation Index (TDVI), Soil Adjusted Vegetation Index (SAVI), Infrared Percentage Vegetation Index (IPVI), Greenness Index (G1 and G2) and Enhanced Vegetation Index (EVI1 and EVI2) were calculated. To select the best variables and the equation for estimating LAI, simple regression (linear, quadratic and exponential) and multiple linear regression (Backward and Forward) methods were used. Finally, to validate and assess the accuracy of the presented models, the mean square error (RMSE), Mean Absolute Error (MAE), Point accuracy based on a percentage of actual value (E%) and correlation coefficient (r) was used.
    Results and Discussion
    The results of this study showed that simulation of LAI based on the existing equations in the references using the NDVI, EVI1 and EVI2 indices extracted from Landsat 8 satellite images has low accuracy (RMSE:2.71, 3.65 and 3.65). This confirms the necessity of examining and calibrating equations. The results indicate that the accuracy of the wheat LAI estimation by using the NDVI and SAVI index was increased by exponential functions (RMSE:1.18 and 1, respectively) compared to the linear model (RMSE:1.46 and 1.26, respectively). This increase was due to a more accurate estimation LAI lower than 4 and the fixed value of LAI simulated in a range of actual LAI higher than 6. The accuracy of LAI estimation was increased with combination of two VIs (NDVI and SAVI) compared to the linear model of each index separately. Also, the highest accuracy of LAI estimation from the combination of G2 with SAVI and EVI1 (RMSE: 1.03, 1.03, respectively) was observed due to the higher sensitivity of G2 to medium and high LAI compared to NDVI. In addition, the backward and forward regression model was improved the accuracy of wheat LAI estimation compared to other models, due to the greater sensitivity of this model to LAI higher than 6 (RMSE: 0.87 and 0.95, respectively). Although the accuracy of wheat LAI estimation by the forward regression model was higher than all models, but its calculation requires the use of many parameters.
    Conclusion
    Since LAI is an important biophysical parameter in ecological modeling. Accurate and fast estimation of this parameter in large scale for ecological models such as yield and evapotranspiration, and carbon exchange is very important. Considering the results of this research and the opinions of other researchers, it can be stated that the accuracy of the exponential functions and multiple linear regression (Forward regression model) for estimating LAI was higher than simple linear regression.
    Keywords: Adjustable vegetation indexes, Enhanced vegetation index, Multiple regression, Normalized difference vegetation Index
  • Abdollah Mollafilabi *, Tahmineh Esfandiari Pages 935-948
    Introduction
    Since ancient times, medicinal plants and aromatic herbs have been used by humans to treat diseases and as spices. Cumin (Cuminum cyminum L.) is the dried seed of the herb, a member of the Asteraceae family. Cumin has a long history of use as food flavors, perfumes and medicine. It is an annual herbaceous plant, with a slender, glabrous, branched stem. The cumin plant grows to 30–50 cm tall and is harvested by hand. Its essential oil is used for bactericidal applications, giving smell to some medicines, sterilizing of surgical operation fiber and producing some veterinary and agricultural medicines. In semi-arid area such as Iran, water is the most limiting factor for agriculture. Cumin has a potential to be as a rainfed plant, but supplemental irrigation is needed to produce more productivity. Little information is available about its consumptive use of water. Also, selecting an optimum plant density is necessary for maximum utility of existing environmental parameters (including water, air, light and soil). As a result, inter specific or intra specific competition is minimum. Thus, many researches has been done to determine the best level of irrigation and plant density and their effects on vegetative and generative parameters of agricultural and medicinal plants. In this paper we aimed to study the effects of different planting dates and irrigation regimes on seed yield and essential oil yield of cumin as an important medicinal plant under the climatic conditions of Torbat-e Jam climatic conditions, Iran.
    Materials and Methods
    In order to study irrigation regimes and planting dates, an experiment was conducted as split plot based on a randomized complete block design with three replications at the Agricultural Research Station, Azad University of Birjand during growing season 2016-2017. Treatments included four planting dates as main plot (25th November, 27th December, 19th February and 19th March) and four irrigation regimes as sub plot (full irrigation, two times irrigation at vegetative stage (stem elongation), two times irrigation at flowering stage and two times irrigation at seed formation). Plant weight, seed weight, number of branches per plant, number of umbels per plant, number of seeds per plant, 1000- seed weight, seed yield, biological yield, essential oil content and harvest index The treatments were run as an analysis of variance (ANOVA) to determine if significant differences existed among treatments means. Multiple comparison tests were conducted for significant effects using the Duncan’s test.
    Results and Discussion
    The results showed that the interaction effect of planting dates and irrigation regimes were significant on number of branches per plant, seed yield and biological yield. The simple effect of planting date was significant on number of seeds per umbel, plant height, essential oil percentage, 1000-seed weight and harvest index. The highest seed yield and biological yield were observed in planting at 27th December + full irrigation. The results for correlation coefficients between yield and yield components revealed that there was a positive and significant correlation between these criteria. The highest coefficient was calculated for seed yield and biological yield (r=0.95).
    Conclusion
    Agronomic management strategies had significantly effect on growth, yield, and yield components of cumin. In conclusion, according to the results, full irrigation combined with planting at 27th December could produce optimum seed yield and biological yield in cumin under semi arid climatic conditions. Generally, irrigation regimes and planting date are two safe and effective technique for agronomic management that may decrease the necessity for chemical approaches to crop. On the whole, results of this study revealed that early sowing was more successful, evident from relatively high yields. Considering water shortages that the world will face in the future, winter planting in those environments susceptible to water stress conditions will have higher water use efficiency compared to late sowing time.
    Keywords: 1000-seed weight, Drought, Full irrigation, Water shortages