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پژوهشهای زراعی ایران - سال نوزدهم شماره 2 (پیاپی 62، تابستان 1400)

نشریه پژوهشهای زراعی ایران
سال نوزدهم شماره 2 (پیاپی 62، تابستان 1400)

  • تاریخ انتشار: 1400/05/03
  • تعداد عناوین: 7
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  • مهدیه سلطانی، محمد کافی، احمد نظامی*، حمیدرضا تقی یاری صفحات 107-120

    سیلیسیم از طریق تخفیف اثرات تنش های محیطی و تاثیر بر جذب برخی عناصر ضروری، رشد گیاهان را بهبود می دهد. در این آزمایش، اثر چهار ترکیب سیلیسیم دار (نانوسیلیکا، سیلیکات سدیم، بنتونیت و نانورس) در دو غلظت (1000 و 2000 ppm) بر روی رشد و عملکرد غده های بذری سیب زمینی (Solanum tuberosum Var. Agria)، در سه نوع خاک (رس لوم، لوم و لوم شنی) در شرایط گلخانه بررسی شد. با توجه به عدم رشد و توسعه گیاهان در خاک رس لوم، مقایسه بین تیمارهای اعمال شده فقط در خاک لوم و خاک لوم شنی انجام شد. نتایج به دست آمده نشان داد که علی رغم عدم رشد و توسعه بیشتر برگ و ساقه در گیاهان تحت تیمار سیلیسیم نسبت به تیمار شاهد، خصوصیات مربوط به غده های بذری تیمار شده نسبت به شاهد بهبود یافت و در نهایت باعث افزایش نسبت وزن خشک غده های بذری به وزن خشک اندام هوایی شد. بررسی اثر اعمال ترکیبات سیلیکاته در غلظت های مختلف بر روی تغییرات عملکرد قابل فروش (وزن تر غده های بذری) از طریق آنالیز خوشه ای و تجزیه علیت نشان داد که در هر دو نوع خاک،کاربرد بنتونیت با غلظت 2000 ppm سبب بهبود وزن غده های بذری شد.

    کلیدواژگان: بنتونیت، سیلیسیم، غده های بذری، مینی تیوبر، نانوسیلیکا
  • رحیم ناصری*، امیر میرزایی، امین عباسی صفحات 121-140

    به منظور بررسی اثر قارچ میکوریزا بر فعالیت برخی آنزیم های آنتی اکسیدان و خصوصیات فیزیولوژیکی ارقام مختلف جو در شرایط دیم، آزمایشی مزرعه ای در مزرعه ایستگاه تحقیقات کشاورزی سرابله طی سال زراعی 99-1398 اجرا شد. تیمارهای آزمایشی شامل عامل ارقام جو (محلی، ماهور، خرم و فردان) و تیمار منابع کودی شامل: شاهد (عدم مصرف هیچ منبع کودی)، 50 درصد کود شیمیایی فسفر، قارچ میکوریزا (Glomus mosseae, Glomus etunicatum and Rhizophagus irregularis)، قارچ میکوریزا+50 درصد کود شیمیایی فسفر و 100 درصد کود شیمیایی فسفر بودند. نتایج حاصل از این آزمایش نشان داد که اثر برهمکنش رقم×منابع کودی بر فعالیت برخی آنزیم های آنتی اکسیدان و خصوصیات فیزیولوژیکی تاثیر معنی دار داشت. رقم جو فردان در قارچ میکوریزا+50 درصد کود شیمیایی فسفر موجب افزایش فعالیت های آسکوربات پراکسیداز (7/85 درصد)، گلوتاتیون پراکسیداز (5/86 درصد)، کاتالاز (1/76 درصد)، پراکسیداز (3/77 درصد)، سوپر اکسید دسموتاز (9/76 درصد)، کلروفیلa (6/88 درصد)، کلروفیل b (92 درصد) و موجب کاهش میزان مالون دی آلدیید (9/62 درصد) و پراکسیدهیدروژن (06/96 درصد) گردید و رقم جو محلی در تیمار شاهد (عدم مصرف کود شیمیایی فسفر و قارچ میکوریزا) دارای کمترین میزان فعالیت های آسکوربات پراکسیداز، پراکسیداز، سوپر اکسید دسموتاز و رنگیزه های فتوسنتزی بودند. با توجه به نتایج این پژوهش، در بین ارقام جو دیم مورد استفاده رقم جو فردان به همراه قارچ میکوریزا+50 درصد کود شیمیایی فسفر در زراعت دیم به دلیل بالا بودن صفات فیزیولوژیکی می تواند توصیه گردد.

    کلیدواژگان: آنزیم های آنتی اکسیدان، تنش خشکی، کلروفیل، میکوریزا
  • نورالله تازیکه، عباس بیابانی*، علیرضا صابری، علی راحمی کاریزکی، معصومه نعیمی صفحات 141-151

    در گیاهان، برگ ها، اصلی ترین محل دریافت تابش خورشیدی و تولید مواد فتوسنتزی هستند، به همین دلیل برآورد میزان کاهش عملکرد ناشی از بین رفتن برگ ها، نقش مهمی در مدیریت مزرعه دارد. به منظور بررسی اثر حذف اندام هوایی (برگ و دمبرگ) در مراحل مختلف رشد رویشی بر عملکرد و کیفیت ریشه چغندرقند، آزمایشی به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار در ایستگاه تحقیقات کشاورزی و منابع طبیعی ورسن گرگان در سال زراعی 99-1398 اجرا گردید. عامل اول شامل 6 رقم تجاری چغندرقند پاییزه (5 رقم خارجی و رقم داخلی شریف) و عامل دوم شامل سرزنی در اردیبهشت ماه (مرحله میانی رشد)، سرزنی در خردادماه (مرحله نهایی رشد) و تیمار شاهد (عدم سرزنی) انجام شد. در پایان فصل رشد صفات کمی و کیفی ریشه اندازه گیری شدند. نتایج نشان داد ارقام چغندرقند در صفات درصد قند ناخالص (عیار)، قند خالص، سدیم، پتاسیم، ضریب استحصال شکر و قند ملاس اختلاف معنی داری از خود نشان دادند؛ ولیکن از نظر صفات نیتروژن مضره و الکالیته بین ارقام اختلاف معنی داری مشاهده نشد. سرزنی چغندرقند باعث کاهش درصد قند، نیتروژن و عملکرد ریشه و افزایش میزان الکالیته و پتاسیم ریشه گردید. بیشترین ضایعات عملکرد ریشه زمانی که برگ چغندرقند در مراحل میانی رشد (اردیبهشت ماه) حذف شدند به دست آمد، به طوری که کاهش عملکرد ریشه در سرزنی اردیبهشت ماه نسبت به سرزنی خردادماه بیشتر تحت تاثیر قرار گرفت. در مجموع، مرحله ای از رشد گیاه که حذف برگ صورت می گیرد و فاصله آن تا زمان برداشت بر عملکرد و خواص کیفی چغندرقند موثر می باشد.

    کلیدواژگان: خسارت برگی، درصد قند، مراحل رشد، عملکرد ریشه
  • علیرضا محسنی محمدجانلو*، رئوف سیدشریفی، سعید خماری صفحات 153-167

    به منظور بررسی اثر قطع آبیاری در مراحل زایشی و کاربرد پوترسین و کودهای زیستی بر دوره پر شدن دانه، محتوای کلروفیل و عملکرد گندم، آزمایش فاکتوریلی بر پایه طرح بلوک های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی و منابع طبیعی دانشگاه محقق اردبیلی در سال زراعی 98-1397 اجرا شد. عوامل مورد بررسی شامل آبیاری در سه سطح (آبیاری کامل به عنوان شاهد، قطع آبیاری در 50% مرحله سنبله دهی و قطع آبیاری در 50% مرحله آبستنی (چکمه ای شدن) به ترتیب به عنوان محدودیت ملایم و شدید آبی) و کودهای زیستی در چهار سطح (عدم کاربرد کودهای زیستی به عنوان شاهد، کاربرد میکوریز (Glomus Intraradices)، کاربرد توام سودوموناس (Psedomunas Putida Strain 186) و فلاوباکتریوم (Flavobacterim Spp)، کاربرد توام میکوریز با سودوموناس و فلاوباکتریوم) و محلول پاشی پوترسین در سه سطح (محلول پاشی با آب به عنوان شاهد، کاربرد 5/0 و یک میلی مولار) بودند. از مدل دو تکه ای برای کمی سازی مولفه های پر شدن دانه استفاده شد. مقایسه میانگین ها نشان داد حداکثر وزن دانه (0641/0 گرم)، سرعت پر شدن دانه (28/2 میلی گرم در روز)، طول دوره (7/39 روز) و دوره موثر پر شدن دانه (14/28 روز) در ترکیب تیماریآبیاری کامل با کاربرد توام میکوریز با سودموناس و فلاوباکتریوم و محلول پاشی یک میلی مولار پوترسین و حداقل مقادیر این صفات (به ترتیب 0361/0 گرم، 6/1 میلی گرم در روز، 15/33 و 57/22 روز) در شرایط قطع آبیاری در مرحله آبستنی، عدم کاربرد کودهای زیستی و عدم محلول پاشی پوتریسین به دست آمد که از افزایش به ترتیب 56/77، 5/42، 76/19 و 68/24 درصدی در مقایسه با عدم کاربرد کودهای زیستی و پوترسین در شرایط قطع آبیاری در مرحله آبستنی برخوردار بودند. آبیاری کامل با کاربرد توام میکوریز با سودموناس و فلاوباکتریوم و محلول پاشی یک میلی مولار پوترسین، حجم و وزن خشک ریشه را به ترتیب 37/124 و 47/123 درصد افزایش داد. عملکرد دانه در قطع آبیاری در مرحله آبستنی و ظهور سنبله نسبت به آبیاری کامل کاهش یافت. بیش ترین عملکرد (68/682 گرم در مترمربع) در آبیاری کامل، کاربرد توام سودموناس و فلاوباکتریوم (42/686 گرم در مترمربع) و محلول پاشی یک میلی مولار پوترسین (02/618 گرم در مترمربع) به دست آمد. بر اساس نتایج این بررسی، به نظر می رسد کاربرد کودهای زیستی و پوتریسین می تواند به دلیل بهبود صفات فیزیولوژیک و بیوشیمیایی، عملکرد دانه ی گندم را تحت شرایط محدودیت آبی در مراحل زایشی افزایش دهد.

    کلیدواژگان: سرعت پر شدن دانه، کودهای بیولوژیک، محدودیت آبیاری، میکوریز
  • مهسا محمدی*، مجید پوریوسف، افشین توکلی صفحات 169-184

    به منظور بررسی تاثیر کاربرد اپی‎براسینولید بر تخصیص مواد فتوسنتزی لوبیا، پژوهشی به صورت اسپلیت فاکتوریل در قالب طرح بلوک‏های کامل تصادفی در مزرعه تحقیقاتی دانشگاه زنجان در سال زراعی 1395-1394 اجرا شد. در این پژوهش، آبیاری مطلوب و تنش خشکی در کرت‎های اصلی و ژنوتیپ‎های لوبیا (رقم کوشا و ژنوتیپ COS16) و غلظت‎های مختلف اپی براسینولید (عدم کاربرد هورمون یا شاهد، 2، 4 و 6 میکرومولار) به صورت فاکتوریل در کرت های فرعی قرار گرفتند. در مرحله گل دهی، تنش خشکی اعمال (قطع آبیاری تا رسیدن پتانسیل آب خاک به 5/1- مگاپاسکال) و بوته های لوبیا با اپی براسینولید محلول پاشی شد و سپس آبیاری مجدد صورت گرفت. نتایج نشان داد که اثر اصلی تنش خشکی و نیز هورمون پاشی بر محتوای نسبی آب برگ، میزان پرولین، میزان مالون دی آلدهید، وزن خشک برگ، ساقه، غلاف و کل و عملکرد دانه معنی دار بود. هم چنین، اثر متقابل تنش خشکی در ژنوتیپ ها بر عملکرد دانه معنی دار بود. تنش خشکی باعث کاهش معنی دار وزن خشک برگ، ساقه، غلاف و عملکرد دانه شد و گیاه در شرایط تنش خشکی، مواد فتوسنتزی کمتری را به برگ و ساقه و مواد فتوسنتزی بیشتری را به غلاف، اختصاص داد. بالاترین عملکرد دانه در رقم کوشا در شرایط آبیاری مطلوب (با میانگین 45/3025 کیلوگرم بر هکتار) و پایین ترین میزان این صفت در ژنوتیپCOS16  در شرایط تنش خشکی (با میانگین 89/980 کیلوگرم بر هکتار) مشاهده گردید. کاربرد اپی براسینولید باعث افزایش وزن خشک برگ، ساقه، غلاف و عملکرد دانه در مقایسه با شاهد شد. بالاترین عملکرد دانه با کاربرد 2 میکرومولار اپی براسینولید (با میانگین 2/2068 کیلوگرم بر هکتار) حاصل شد و کاربرد این غلظت، عملکرد دانه را به میزان 07/46 درصد نسبت به شاهد افزایش داد. همچنین، کاربرد اپی‎براسینولید با کاهش در میزان مالون دی‎آلدهید و افزایش در محتوای نسبی آب برگ و میزان پرولین باعث افزایش مقاومت به تنش خشکی شد. بنابراین، کاربرد اپی براسینولید را به‏عنوان راهکاری جهت افزایش عملکرد دانه لوبیا و افزایش مقاومت به خشکی این گیاه می توان پیشنهاد نمود.

    کلیدواژگان: پرولین، تنش خشکی، عملکرد دانه، مالون دی آلدهید، محتوای نسبی آب برگ
  • پرویز رضوانی مقدم*، سرور خرم دل، هدا لطیفی، محمودرضا فرزانه بلگردی، سید جلیل داورپناه صفحات 185-199

    بهینه سازی یکی از راهکارهای موثر مدیریتی برای بهبود کارایی مصرف منابع و کاهش آلودگی های زیست محیطی محسوب می شود. مدل سطح- پاسخ (RSM) مجموعه ای از تکنیک های آماری و ریاضی مورد استفاده برای بهینه سازی نهاده های تولید به شمار می آید. در این مطالعه، بهینه سازی سطوح نیتروژن و آبیاری کینوا با استفاده از طرح مرکب مرکزی (CCD) انجام شد. این آزمایش با 13 تیمار و دو تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد در سال زراعی 97-1396 اجرا شد. تیمارها بر اساس سطح پایین و بالای آبیاری (به ترتیب با 2500 و 7500 مترمکعب در هکتار) و نیتروژن (به ترتیب با صفر و 200 کیلوگرم نیتروژن در هکتار) تعیین شدند. عملکرد دانه، عملکرد بیولوژیک، شاخص های کارایی نیتروژن و کارایی مصرف آب به عنوان متغیر وابسته مورد اندازه گیری قرار گرفتند و تغییرات این متغیرها با استفاده از مدل رگرسیونی ارزیابی شد. به منظور ارزیابی کیفیت مدل پیش بینی شده از آزمون عدم برازش استفاده شد. مقادیر بهینه کاربرد نیتروژن و آب برای مقادیر مطلوب متغیرهای وابسته شامل عملکرد دانه، بازیافت نیتروژن، کارایی مصرف نیتروژن و کارایی مصرف آب در سه سناریوی اقتصادی، زیست محیطی و اقتصادی- زیست محیطی بررسی شد. نتایج نشان داد که اثر جزء خطی و درجه دو بر تمام صفات مورد مطالعه معنی دار بود. اثر متقابل دو عامل نیتروژن و آبیاری تنها بر کارایی مصرف نیتروژن و کارایی مصرف آب معنی دار بود. آزمون عدم برازش در مورد هیچ کدام از صفات معنی دار نشد که این امر نشان دهنده ی برازش مطلوب مدل رگرسیون درجه دو کامل بود. بیشترین عملکرد دانه با 4/3835 کیلوگرم در هکتار برای مصرف 200 کیلوگرم نیتروژن و 7500 مترمکعب در هکتار آبیاری به دست آمد. در سناریوی اقتصادی- زیست محیطی کاربرد 90 کیلوگرم نیتروژن در هکتار و 6000 مترمکعب در هکتار آبیاری موجب حصول کارایی مصرف نیتروژن با 93/15 کیلوگرم دانه بر کیلوگرم نیتروژن خاک، بازیافت نیتروژن 50 درصد، کارایی مصرف آب 5/0 کیلوگرم در مترمکعب و 3121 کیلوگرم در هکتار عملکرد دانه شد. به طور کلی، به نظر می رسد میزان مصرف منابع به ویژه آب و نیتروژن بر اساس سناریوی اقتصادی- زیست محیطی می تواند به عنوان راهکاری مطلوب در توسعه سطح زیر کشت و تولید پایدار کینوا به عنوان گیاهی جدید مد نظر قرار گیرد.

    کلیدواژگان: آزمون عدم برازش، سناریوی اقتصادی- زیست محیطی، طرح مرکب مرکزی، کارایی مصرف منابع، گیاه جدید
  • معصومه فرهادی، محسن جهان*، محمد بنایان اول صفحات 201-217

    بررسی تاثیر تغییر اقلیم بر تولیدات کشاورزی در بعد زمانی- مکانی، مطالعات هواشناسی کشاورزی، شبیه سازی عملکرد گیاهان زراعی و تولید سناریوهای اقلیمی، نیازمند مجموعه داده های هواشناسی دقیق و استاندارد است. این در حالی است که داده های مشاهداتی تاریخی در بسیاری از مناطق در دسترس نبوده و یا ناقص است؛ بنابراین، داده های شبکه بندی شده یا داده های آب و هوایی تولید شده به عنوان جایگزینی در این مناطق مورد استفاده قرار می گیرند. در پژوهش حاضر، امکان استفاده از مجموعه داده های AgMERRA برای پر کردن خلاء داده های تاریخی ناقص و گمشده در هفت ایستگاه هواشناسی سینوپتیک در استان خراسان شمالی در بازه زمانی 2010-1980 مورد بررسی قرار گرفت. نتایج واسنجی با استفاده از شاخص های ارزیابی کارایی مدل نظیر ضریب تبیین (R2)، شاخص توافق (d)، جذر میانگین مربعات خطا (RMSE)، جذر میانگین مربعات خطای نرمال شده (NRMSE)، میانگین خطای اریبی (MBE) نشان داد که در تمامی مناطق مورد مطالعه، داده های شبکه بندی شده AgMERRA برای تشعشع خورشیدی، دمای حداقل، دمای حداکثر، به استثنای بارندگی روزانه و رطوبت نسبی در دمای حداکثر، تطابق (92/0> d و 30%< NRMSE)و همبستگی خوبی (96/0 ≥ r ≥ 81/0) با داده های ایستگاهی در مناطق خشک، نیمه خشک، معتدل و سرد و کوهستانی استان خراسان شمالی دارد. اگرچه زمانی که داده های روزانه بارندگی به صورت داده های ماهانه تجمیع شدند، همبستگی بهتری حاصل شد. به طور کلی نتایج حاصل از این پژوهش نشان داد که می توان از سری داده های AgMERRA برای مطالعات اقلیمی، تجزیه و تحلیل، برنامه ریزی و مدیریت بخش کشاورزی در حوزه استان خراسان شمالی استفاده نمود.

    کلیدواژگان: اعتبارسنجی، تغییرات زمانی-مکانی، داده های ایستگاهی، هواشناسی کشاورزی
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  • M Soltani, M Kafi, A Nezami *, H. R Taghiyari Pages 107-120
    Introduction

    Many experiments have shown that Silicon (Si) can reduce the effect of both biotic and abiotic stresses in plants caused by plant diseases, pest damage, salinity, drought, heavy metal toxicity, nutrient imbalance, water logging, high radiation, high temperature, wounding, and freezing. It has been indicated that silicon has a beneficial role in plant nutrition such as enhancement in absorbing nitrogen, phosphor, potassium and zinc. Beneficial results of silicon application on plant growth and physiology made farmers and researches to use silicon as a fertilizer. Silicon fertilizers are applied as slag, compost, rice straw, calcium and sodium silicates in both foliar and soil applications. Potato is not considered as a Si-accumulating but studies have implied that Si supply may alleviate damaging effects that result from drought and also reduce stem lodging and increase tuber yield  increased leaf area, specific leaf area, and pigment concentration (chlorophyll a and carotenoids) as well as photosynthesis and transpiration rates of well watered potato plants.

    Materials and Methods

    This experiment was conducted as factorial based on completely randomized design with three replications, in department of agronomy, Ferdowsi university of Mashhad, Iran, in 2015. In this research, the effects of four different silicon compounds (Nano-silica, sodium silicate, hydrophilic Bentonite (Nano-clay), and Bentonite), in two concentrations (1000 ppm and 2000 ppm) on the growth characteristics of potato Minitubers (Solanum tuberosum Var. Agria) plants and production under three different soil texture (clay loam, loam and sandy loam), were investigated. In order to determine the best treatment in each soil, variance analysis was done along with cluster analysis, stepwise multi regression analysis and path analysis, and the results of all analysis were compared. Resultsand

    Discussion

    Due to the lack of development of plants in clay loam soil, the comparison between treatments was done only in loam soils and sandy loam soils. The results showed that despite the lack of leaf and stem development in silicon treated plants, the Minituber characteristics improved compared to the control, which resulted in an increase in the ratio of Minituber dry weight to shoot dry weight. based on plant performance, Cluster analysis for loam soil categorized silicate treatments in 3 groups: first (control, Bentonite (2000 ppm), Nano-silica (2000 ppm)), second (Nano-clay (1000 ppm), Bentonite (1000 ppm), Nano-silica (1000 ppm)) and third (Nano-clay (1000 ppm), Sodium Silicate (1000 ppm), Sodium Silicate (2000 ppm)). In loam sand soil this grouping was in four groups: first (control, Bentonite (1000 ppm), Nano-clay (1000 ppm)), second (Nano-clay (2000 ppm), Nano-silica (2000 ppm), Nano-silica (1000 ppm)), third (Bentonite (2000 ppm), Sodium Silicate (2000 ppm)) and forth (Sodium Silicate (1000 ppm)). Path analysis showed in loam soil three traits (leaf dry weight, total plant Minituber volume, total plant Minituber dry weight) have the most direct and indirect effect on Minituber fresh weight (as potato yield. In loam sand soil four traits (mean Minituber diameter, leaf area, total plant Minituber volume, total plant Minituber dry weight) were indicated to have the most direct and indirect effect on Minituber fresh weight (as potato yield).

    Conclusions

    Investigating the effect of applying silicate treatments in different concentrations on Minituber wet weight (as Minituber yield) by cluster analysis and path analysis showed that in both soils, Bentonite (2000 ppm) had the most effect on traits responsible for Minituber wet weight changes.

    Keywords: bentonite, Mintubers, Nanoclay, nanosilica, Silicon
  • R Naseri *, A Mirzaei, A Abbasi Pages 121-140
    Introduction

    Mycorrhiza fungus is of special importance in organic agriculture and in relation to the coexistence of all root characteristics of the host plant is affected and also improves the water relationship in the host plant.  With application of mycorrhizal fungus, the plant absorbs soil water better and as a result, by increasing the relative moisture content of the leaves, the stomata are open for a longer time and carbon dioxide processing is done optimally, resulting in more photosynthesis, which ultimately leads to increased yield. The aim of this research in rainfed agriculture is to reduce the stresses on rainfed wheat. In rainfed wheat cultivation, the plant gets its water requirement from rainfall. In most cases, the plant water needs are not met in this way. Due to the reduction of grain yield of rain-fed barley cultivars, new achievements can be reached by investigating the role of plant growth-promoting bacteria on physiological and biochemical traits under rain-fed conditions. Considering that no research has been reported on the role of plant growth promoting bacteria on rainfed barley in the country and especially in Ilam province. Therefore, the present experiment was conducted to investigate the effect of plant growth promoting bacteria on the activity of antioxidant enzymes and physiological traits of rain-fed barley cultivars.
    Materials and

    Methods

    In order to investigate the effect of inoculation with mycorrhizal fungi on some physiologic and biochemicaltraits of barley cultivars in rainfed conditions, a factorial field experiment was carried out in the form of a randomized complete block design with three replications in the farm station of Sarablah Agricultural Research Center during 2019-2020 cropping season. Experimental treatments including factor of barley cultivars (Mahali, Mahour, Khoram and Fardan) and fertilizer sources treatment including: control (without fertilizer source), 50% P fertilizer, mycorrhizal fungus (Glomus mosseae, Glomus etunicatum and Rhizophagus irregularis), mycorrhizal fungi + 50% P chemical fertilizer and 100% P chemical fertilizer.
    Results and

    Discussion

    The results of this experiment showed that the interaction between cultivar×fertilizer sources had a significant effect on the activity of some antioxidant enzymes and physiological properties. Fardan cultivar× mycorrhizal fungi +50% P chemical fertilizer increases the activities of ascorbate peroxidase (14.3 µmolmin-1 mg protein-1), gluthathion peroxidase (3.5 µmol.min-1 .mg protein-1), catalase (12.1 µmolmin-1 .mg protein-1), peroxidase (14.8 µmol.min-1 .mg protein-1), super oxid dismutas (25.4 µmol.min-1 .mg protein-1), chlorophyll a (3.5 mg.g-1 fresh weight), chlorophyll b (3.3 mg.g-1 fresh weight) and reduces malonde aldeyede (20.4 nmol.g fresh weigh leaf) and hydrogen Peroxide (0.26 mmol.g-1 FW) and Mahali cultivar× control treatment (without fertilizer sources) had the lowest activities of ascorbate peroxidase, peroxidase, superoxide dismutase and photosynthetic pigments.

    Conclusions

    The results of this study showed that in the dryland conditions of the region, physiological traits (leaf chlorophyll content) were significantly reduced in all studied barley cultivars. In this study, the maximum activity of hydrogen peroxide and malondealdeyede in the Mahali cultivar×control treatment was observed, but when inoculation was used with mycorrhizal fungus, observed an increase in physiological characteristics. Fardan cultivar×Mycorrhiza+50% P fertilizer with maximum activity of photosynthetic pigments and antioxidant enzymes (superoxide desmutase, catalase and peroxidase) which resulted in increased growth and yield. According to the results of this study, among the rainfed barley cultivars used, Fardan cultivar with mycorrhizal fungi +50% P fertilizer can be recommended in rainfed agriculture of the region.

    Acknowledgements

    This research was derived from a research project that was carried out at Sarablah Agricultural Research Station. Thanks to all the colleagues who accompanied and helped the authors during the implementation of this study.

    Keywords: Antioxidant enzymes, Chlorophyll, Drought stress, Mycorrhiza
  • N Tazikeh, A Biabani *, A Saberi, A Rahemi Karizaki, M Naeimi Pages 141-151
    Introduction  

    Sugar beet, scientifically known as Beta vulgaris L, is allogamous, diploid, biennial plant of the spinach genus that is cultivated to produce storage roots. The growth period of sugar beet, depending on environmental conditions and genotype, varies from 5 to 9 months and is known as a late maturing plant. Therefore, estimating the yield reduction due to leaf fall plays an important role in farm management. In addition to the effects of stressors, some farmers may use sugar beet leaves to raise livestock during the growing season. In this case, too, the leaves are damaged. In the experiment of complete removal of leaves in three sugar beet cultivars, it was observed that complete removal of leaves in Antek and Vico cultivars led to reduced root yield and subsequently white sugar yield was significantly reduced, but In Sharif cultivar, leaf removal had no significant effect on root yield and sugar yield. They also reported that leaf removal increased the percentage of root sugar in Sharif cultivar. Effect of leaf removal time on quantitative and qualitative characteristics of autumn sugar beet cultivars in Gorgan region.

    Materials and Methods

    This experiment was carried out in factorial design during the 2019-2020 crop year in Varsen of Gorgan based on randomized complete block design with three replications. The first factor includes 6 autumn sugar beet cultivars including Monotana, Jerra-kws, Rosagold, Chimneh, Veles and Sharif and the second factor includes three levels, pruning in May (leaf development), pruning in June (reducing leaf development) and no pruning (control). Pruning was done using a sickle and the entire aerial part (petiole and leaves) was cut from a height of 5 cm above the crown. Seed bed preparation operations including plowing, retorting, leveling and farrowing were performed before planting. According to the planting plan, they were planted by hand on top of the ridges on November 2019. At the end of the growing season of each harvested plant, root yield and qualitative traits were calculated. The most common method of measuring sugar percentage by polarimetry method was calculated using saccharimeter, sodium and potassium by flame photometry method, harmful nitrogen by aqueous number method and other qualitative characteristics. The analyzed traits were analyzed using SAS software and the means were compared by LSD method at a statistical level of 5%.

    Results and Discussion

    Sugar beet cultivars showed significant differences in sugar content (grade), sodium, potassium, extractable sugar content, sugar and molasses extraction coefficient; However, no significant differences were observed between cultivars in terms of harmful nitrogen, alkalinity and root dry matter. Leaf pruning treatments except sodium and molasses were significant in other studied traits. The interaction between cultivars and pruning has also been significant in potassium and molasses traits. Significant differences were observed between the treatments by applying pruning treatment; So that the highest percentage of sugar (14.7%) was observed in the control treatment and the lowest percentage of sugar was observed in the June treatment (12%). The highest root yield was related to Chamineh cultivar with an average of 98 tons per hectare and the lowest root yield was related to Rosagold cultivar with an average of 80 tons per hectare. Due to the decrease in leaf production at the end of the sugar beet growing season, the amount of damage caused by root yield in leaf removal treatment in the final stages of growth (June pruning) is much less than the effect of leaf removal in the middle stage of growth.

    Conclusions 

    Removal of sugar beet leaves in the final stages of growth had an effect on root quality properties such as sugar content, extractable sugar percentage and sugar extraction coefficient and root yield and reduced the mentioned traits. Root impurities also increased due to defoliation. Most yield losses were obtained when sugar beet leaves were removed or eliminated in the middle stages of growth (May pruning).

    Keywords: Leaf damage, Growth stage, Percentage of sugar, Root yield
  • A Mohseni Mohammadjanlou *, R Seyedsharifi, S Khomari Pages 153-167
    Introduction

    Drought is the most severe abiotic stress factor limiting plant growth and crop production. Many physiological processes in plants are impaired by drought stress. Also, this stress can damage the photosynthesis of plants, pigments and plastids reduce chlorophyll a, chlorophyll band other carotenoids, hydrolyze proteins and prevalent photochemical reactions in most plants. The response of plants to drought stress depends on several factors such as developmental stage, severity, duration of stress, and cultivar genetics. Several strategies have been developed in order to decrease the water limitation-induced toxic effects on plant growth, among them use of bio fertilizers and putrescine play a key role in yield improvement. The aim of this study was to investigate the effects of irrigation withholding during reproductive stage and putrescine and bio fertilizers application on grain filling period, chlorophyll content and yield of wheat.

    Materials and Methods

    A factorial experiment was conducted based on randomized complete block design with three replications at the research farm, faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili during 2018-2019. Factors experiment were included irrigation at three levels (full irrigation as control, irrigation withholding in 50 percent of heading stage and irrigation withholding in 50 percent booting stage as moderate and severe water limitation respectively) and bio fertilizers at four levels (no bio fertilizer, application of mycorrhiza (Glomus Intraradices), both application Psedomunas(Psedomunas Putida Strain 186)and Flavobacterim Spp, application of mycorrhiza  with Psedomunas and Flavobacterim), foliar application putrescine in three levels (foliar application with water as control and foliar application 0.5 and 1 mM of putrescine). Mycorrhiza fungiwas purchased from the Zist Fanavar Turan corporation and soils were treated based on method of Gianinazzi et al. (2001). Psedomunas and flovobacterium were isolated from the rhizospheres of wheat by Research Institute of Soil and Water, Tehran, Iran. Two part linear model was used to quantifying the grain filling parameters. In this study, total chlorophyll, chlorophyll a, b, carotenoid, grain filling components and yield of wheat were investigated. Grain dry weight and number were used to calculate the average grain weight for each sample. Total duration of grain filling was determined for each treatment combination by fitting a bilinear model: 
    Effective grain filling duration (EGFD) was calculated from the below equation: EGFD = the highest grain weight (g)/rate of grain filling (g.day-1).

    Results and Discussion

    Means comparison showed that maximum of grain weight (0.0641 g), grain filling rate (2.28 mg.day-1), grain filling period (39.7 day) and effective grain filling period (28.14 day) were obtained in full irrigation, application of mycorrhiza with Psedomunas and Flavobacterim and foliar application 1 mM of  putrescine and the least of these traits (0.0361 g, 1.6 mg. day-1, 33.15 and 22.57 days respectively) were obtained in irrigation withholding at booting stage and no application of putrescine and bio fertilizers, there were an increase about 77.56%, 42.5%, 19.76% and 24.68% in this treatment compounds in comparison with withholding at booting stage and no application of putrescine and bio fertilizers. Full irrigation, both application Psedomunas and Flavobacterim withmycorrhiza and foliar application 1 mM of putrescine increased volume and root dry weight 124.37 and 123.47% respectively. Grain yield under irrigation withholding in heading and booting stages decreased in comparison with full irrigation. The highest grain yield was obtained in full irrigation (682.68 g.m-2), both application Psedomunas and Flavobacterim(686.42 g.m-2) andfoliar application 1 mM of putrescine (618.02 g.m-2).

    Conclusions

    Based on the results of this study, it seems both application of mycorrhiza with Psedomunas and Flavobacterim and foliar application 1 mM of putrescine with full irrigation can increase grain yield of wheat due to improve biochemical and physiological traits under water limitation condition in reproductive stages.

    Keywords: Bio fertilizers, Grain filling rate, Mycorrhiza, Water limitation
  • M Mohammadi *, M Pouryousef, A Tavakoli Pages 169-184
    Introduction

    Common bean (Phaseolus vulgaris L.) is a food crop with high protein, fiber, and minerals. One of the important issues in the formation of seed yield is how photosynthetic materials are allocated in plants. This may be especially important when the plant is experiencing drought stress. Brassinosteroids are a group of steroid hormones that have been implicated in a wide range of physiological processes. Brassinosteroids increase crop yield by altering plant metabolism and protecting plants from environmental stresses. Considering that one of the major problems of agriculture is water shortage, the present study was assessed aimed to investigate the effect of Epibrassinolide application on the allocation of photosynthetic materials and some traits related to drought resistance in two common bean genotypes under optimal irrigation and drought stress conditions and the possibility of increasing common bean seed yield by using this hormone.

    Materials and Methods

    In order to investigate the effect of Epibrassinolide application on photosynthetic material allocation and the possibility of increasing common bean seed yield by application of this hormone, an experiment was conducted in split factorial based on randomized complete block design at the research farm of the University of Zanjan during 2016-2017. In this experiment, optimal irrigation and drought stress were applied to main plots and common bean genotypes (at two levels of Kusha cultivar and COS16 genotype) and different concentrations of Epibrassinolide (at four levels of no application or control, 2, 4, and 6 μM) were allocated to sub plots as factorial. In the flowering stage, drought stress was applied and simultaneously with drought stress, common bean plants, were sprayed with Epibrassinolide. In this study, relative water content, proline content, and malondialdehyde content were studied at the peak of the drought stress. Also, dry weights of leaf, stem, and pod and the ratio of leaf, stem, and pod dry weights to total plant weight were studied at two times (peak of the drought stress and one week after re-irrigation).

    Results and Discussion

    The results showed that drought stress decreased dry weights of leaf, stem, pod, and seed yield compared to the optimal irrigation. Common bean plant under drought stress allocated less photosynthetic materials to leaves and stems and more photosynthetic materials to pods. The Kusha cultivar under optimal irrigation had the highest seed yield (with an average of 3025.45 kg ha-1) and the COS16 genotype under drought stress had the lowest one (with an average of 980.89 kg ha-1). The Kusha cultivar in optimal irrigation condition was the superior genotype due to its high seed yield, but drought stress had a more negative effect on the Kusha cultivar. Also, application of different concentrations of Epibrassinolide increased dry weights of leaf, stem, pod, and seed yield compared to the control. The highest seed yield was obtained by application of 2 μM Epibrassinolide (with an average of 2068.2 kg ha-1). So that, application of this concentration increased the seed yield by 46.07% compared to the control. Epibrassinolide application also increased the drought stress tolerance by decreasing the amount of malondialdehyde and increasing the relative leaf water content and proline content.

    Conclusions

    Therefore, application of Epibrassinolide can be suggested as a solution to increase common bean seed yield and increase drought tolerance of this plant. In addition, obtaining comprehensive information on the positive effects of Epibrassinolide requires the study of this hormone in different climatic conditions.

    Keywords: Drought stress, Malondialdehyde, Proline, Relative water content, Seed yield
  • P Rezvani Moghaddam *, S Khorramdel, H Latifi, M. R Farzaneh Belgerdi, S. J Davarpanah Pages 185-199
    Introduction

     The optimum resource level in agro-ecosystems should be determined to decrease production costs, conserve resources, and mitigate environmental pollutions. Optimization is an effective and sustainable management approach to conserve resources and decline environmental pollutions. Response surface methodology (RSM) is defined as a collection of mathematical and statistical techniques used to develop, improve, or optimize a product. RSM is a statistical technique for optimization of multiple factors that determine optimum rates by combining experimental designs. Quinoa (Chenopodium quinoa Willd.) is a pseudocereal, seed-producing annual crop, and a staple food in South America in ancient times, indigenous to the Andean region of South America, particularly Bolivia, Peru, Ecuador, and parts of Chile, which has the potential to grow with low inputs, mostly water and tolerate a variety of biotic and abiotic stresses. Quinoa seed is gluten-free foods, good sources of carbohydrates, good-quality proteins, lipids, vitamins, minerals, and bioactive compounds, with all the essentials, trace elements, and many vitamins. In this work, optimization of nitrogen and water rates on quinoa was done.

    Materials and Methods  

    An experiment was conducted using Central Composite Design (CCD) with 13 treatments and two replications at the Research Field of the Ferdowsi University of Mashhad during the growing season of 2017-2018. The treatments were allocated based on low and high water (2500 and 7500 m3 ha-1, respectively) and nitrogen (0 and 200 kg ha-1, respectively) levels. Seed yield, biological yield, N recovery, N use efficiency (NUE), and water use efficiency (WUE) were calculated as dependent variables, and changes of these variables were evaluated by a regression model. A lack-of-fit test was used to evaluate the quality of the fitted model. The adequacy of the model was tested by analysis of variance. The quality of the fitted models was judged using the determination coefficient (R2). Finally, the optimum nitrogen and water rates were computed based on economic, environmental, and economic-environmental scenarios.

    Results and Discussion 

    The results showed that the effect of linear and square components was significant on all studied characteristics. The interaction effect of full quadratic was significant on NUE and WUE. Lack of fit test had no significant effect on the studied traits. The full square model for the response variables gave insignificant lack-of-fit, indicating that the data were satisfactorily explained. Surface-response results of the effect of irrigation and nitrogen levels on grain yield and biological yield showed that with increasing nitrogen consumption and irrigation, quinoa yield indices increased, but in terms of nitrogen use, with increasing nitrogen consumption more than 100 kg ha-1, the grain yield increased with more slope. The highest value of seed yield was observed for 7500 m3 ha-1 irrigation and 200 kg nitrogen ha-1 with 3835.4 kg ha-1. Optimum nitrogen and water rates were suggested to determine the target range of dependent variables based on three scenarios: economic, environmental, and eco-environmental. It is necessary to use 169.7 kg nitrogen ha-1 and 7500 m3 ha-1 irrigation to obtain optimum conditions under the economic scenario. The optimum nitrogen and irrigation rates based on environmental scenarios were computed from 18.18 kg nitrogen ha-1 and 3409 m3 ha-1 irrigation water. Application of 88.57 kg nitrogen ha-1 and 5909 m3 ha-1 irrigation water was found to be the optimum conditions for the eco-environmental scenario (NUE, N recovery, seed yield, and WUE were calculated with 15.93 kg seed kg-1 N, 50.04%, 3120.76 kg ha-1, and 0.5 kg seed m-3 water, respectively).

    Conclusions

    Increasing nitrogen led to increased seed yield and decreased nitrogen use efficiency, whereas increasing irrigation caused an increase in seed yield and nitrogen use efficiency. In general, it seems that resource use based on the eco-environmental scenario may be a suitable cropping approach for the sustainable production of quinoa as a new crop.

    Keywords: Central composite design, Economic- environmental scenario, Lack of fit, New crop, Sustainable production
  • M Farhadi, M Jahan *, M Bannayan Aval Pages 201-217
    Introduction 

    Investigating the effect of climate change on agricultural production in spatio-temporal dimension, development and use of crop management decision-support tools, supporting and target agronomic research and policy require a series of accurate and standard meteorological data. The weather station databases are often regional in coverage, and it can have extensive gaps in station coverage over time. It may also contain errors in climate records, station coordinates or elevation. While historical observational data are incomplete or not available in many areas; therefore, gridded weather data are used as an alternative in these areas. An issue is the agreement of gridded with measured weather data and the degree to which this agreement may influence the utility of gridded for agricultural research.  In this study, the possibility of using AgMERRA data series to fill the gap of incomplete and missing historical data in seven synoptic meteorological stations in North Khorasan province in the period (1980-2010) was investigated.

    Materials and Methods

    Historical daily measured weather data (maximum and minimum air temperature, sunshine hours, relative humidity, and precipitation) for the 1980 to 2010 period, were obtained from the 7 synoptic weather stations (Bojnord, Shirvan, Farooj, Esfarayen, Mane-Semelghan, Raz-Jargalan, Jajarm) across Northern Khorasan.  The robustness of AgMERRA dataset was investigated through statistical validation indices including RMSE (Root Mean Square Error), R2 (Coefficient of Determination), d (d Index of Agreement), NRMSE (Normalized Root Mean Square Error) and MBE (Mean Bias Error). 

    Result and Discussion

    Strong positive correlations were observed between simulated values ​​of maximum and minimum temperature with observational values (0.81 ≤ r ≤ 0.96). The NRMSE was excellent and good for all stations (7.76 ≤ NRMSE ≤ 15.81). Overall, the high agreement index (d ≥ 0.92), as well as the small values ​​of the MBE, indicated good agreement between the observed and predicted data for the maximum and minimum temperature variable. The solar radiation simulations correlated well with the observed values (0.86 ≤  r ≤ 0.93). The high values for agreement index were obtained in four stations (0.96 ≤ d ≤ 0.98). But the NRMSE for Bojnourd, Esfarayen, and Jajarm stations was ranked in moderate class (20 < NRMSE < 30), and weak class for Mane Semelghan station (NRMSE = 32.31). Other stations (Shirvan, Farooj, and Raz-Jargalan) did not have station observation values for the radiation variable. AgMERRA had a relatively high ability to simulate the relative humidity variable at maximum temperature for Shirvan, Farooj, Esfarayen, and Jajarm stations. The agreement index for these stations was between 0.92 and 0.94, also those NRMSE was ranked in the good class. The coefficient of correlation (r) between the predicted values with the observational data of the relative humidity at maximum temperature )Rhstmax(  ranged from 0.40 to 0.70. The low r value can be related to the topographic conditions and low vegetation of these areas. AgMERRA daily precipitation data had excellent NRMSE. Due to the weak correlation between the predicted daily precipitation data and the observational data, the total monthly precipitation of each station was examined, which showed better correlation and NRMSE than of the daily precipitation. Considering the monthly time scale compared to the daily, NRMSE reduced from a high class to a good class, also a strong correlation was obtained especially for Raz- Jarglan (0.88), Esfarayen (0.84), and Mane Semolghan (0.80) stations.

    Conclusions

     AgMERRA gridded dataset for maximum and minimum temperature, solar radiation excluding daily precipitation and relative humidity at maximum temperature showed high accordance (d> 0.92 and NRMSE <30%) and strong correlation (0.81 ≤ r ≤ 0.96) with station data in arid, semiarid, temperate, cold and mountainous areas of North Khorasan province.  However, a more strong correlation was obtained when daily precipitation data were aggregated into monthly data. In general, the validation results of the AgMERRA simulated values with 7 synoptic stations indicated its robustness and power to produce meteorological data series. So AgMERRA data series can be used for climate studies, analysis, planning and decision making in agriculture section in North Khorasan province.

    Keywords: Agricultural meteorology, Spatio-temporal changes, Stations data, Validation