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بوم شناسی کشاورزی - سال هشتم شماره 2 (تابستان 1395)
  • سال هشتم شماره 2 (تابستان 1395)
  • تاریخ انتشار: 1395/06/27
  • تعداد عناوین: 12
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  • علیرضا کوچکی، لیلا تبریزی، مسعود کیخاآخر، عقیل روحی صفحات 153-168
    به منظور مطالعه ویژگی های کمی و کیفی بذور گیاهان دارویی سیاهدانه (Nigella sativa L.)، اسفرزه (Plantago ovata Forsk.) و رازیانه (Foeniculum vulgare Mill.) تحت شرایط کاربرد نهاده های آلی، آزمایشی به صورت طرح بلوک های کامل تصادفی با چهار تیمار کودی شامل کود گاوی، کمپوست زباله شهری، کمپوست بقایای قارچ و تیمار شاهد (عدم کاربرد کود) در سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد طی دو سال زراعی 89-1388 و 90-1389 برای سه گونه گیاه دارویی نامبرده اجرا شد و سپس خصوصیات کیفی جوانه زنی بذور حاصل از تیمار های مذکور به صورت فاکتوریل در قالب طرح کاملا تصادفی با 12 تیمار و سه تکرار در آزمایشگاه بذر پردیس کشاورزی و منابع طبیعی دانشگاه تهران ارزیابی شدند. عملکرد بیولوژیک و بذر، وزن هزاردانه، شاخص برداشت و برخی شاخص های کیفی بذر شامل طول، عرض و قطر، درصد و سرعت جوانه زنی، شاخص بنیه بذر، طول و وزن خشک گیاهچه سه گیاه دارویی اسفرزه، سیاهدانه و رازیانه مورد مطالعه قرار گرفتند. بر اساس نتایج موجود، تیمار های مورد بررسی در مزرعه به طور معنی داری سبب افزایش عملکرد بذر و بیولوژیک هر سه گیاه شدند به طوری که در هر دو سال، کمپوست بقایای قارچ بیشترین تاثیر را بر افزایش این صفات نسبت به تیمار شاهد داشت. نهاده های کودی بر شاخص برداشت اسفرزه و سیاهدانه در طی دو سال تاثیرگذار نبودند، در حالی که بر شاخص برداشت گیاه رازیانه تاثیر معنی دار داشتند. استفاده از کمپوست بقایای قارچ در سال اول و کمپوست زباله شهری در سال دوم به ترتیب وزن هزاردانه اسفرزه و سیاهدانه را تحت تاثیر قرار دادند. همچنین، تیمار های کودی میزان درصد و سرعت جوانه زنی، طول و وزن خشک گیاهچه و بنیه بذر را در هر سه گیاه نسبت به تیمار شاهد افزایش دادند و بیشترین مقدار این صفات در تیمار کود دامی مشاهده شد. استفاده از کمپوست بقایای قارچ منجر به حصول بیشترین میانگین طول بذر در گونه های مورد مطالعه شد. بذور رازیانه با کاربرد کمپوست بقایای قارچ بیشترین طول بذر را در بین گونه ها و تیمار های کودی مورد استفاده نشان دادند.
    کلیدواژگان: بنیه بذر، سرعت جوانه زنی، شاخص برداشت، کمپوست، کود دامی
  • امیر حجارپور، نسیم مقدادی، افشین سلطانی، بهنام کامکار صفحات 169-181
    تغییرات بسیار اندک شرایط اقلیمی نسبت به وضع معمول بر توان تولیدی گیاهان زراعی اثرات شگرف خواهد داشت، بنابراین ارزیابی میزان کارایی راه های سازگاری به شرایط آینده برای توسعه پایدار یک ناحیه یا منطقه ضروری است. هدف از این مطالعه ارزیابی راهکارهای سازگاری کشت دیم گیاه نخود به شرایط تغییر اقلیم (افزایش چهار درجه سانتی گرادی دما، کاهش 10 درصدی بارندگی و افزایش دو برابری دی اکسید کربن) در استان زنجان با استفاده از مدل SSM-Chickpea بود. در شرایط اقلیمی آینده، میانگین عملکرد استان به طور متوسط با 4/38 درصد افزایش به 1036 کیلوگرم در هکتار خواهد رسید که اختلاف معنی داری با شرایط فعلی (760 کیلوگرم در هکتار) دارد. سه روش مدیریتی (تسریع در کاشت، استفاده از ارقام زودرس و تلفیقی از زودرسی و تسریع در کاشت) جهت سازگاری با تغییرات اقلیمی آینده شبیه سازی و مورد ارزیابی قرار گرفت. نتایج نشان داد که استفاده از ارقام زودرس به همراه تسریع در کاشت در شرایط آینده میانگین عملکرد استان را تا 5/94 درصد نسبت به شرایط فعلی افزایش می دهد و به 1452 کیلوگرم در هکتار می رساند. کاهش طول دوره رشدی گیاه و عدم برخورد با دماهای فوق مطلوب در هنگام پر شدن دانه، توزیع آب بین فاز رویشی و زایشی در اثر کم شدن دوره رشد رویشی و فرار از تنش خشکی آخر فصل به علت منطبق شدن دوره رشدی گیاه با فصل رشد از جمله دلایل افزایش عملکرد نخود در شرایط به کارگیری راهکارهای سازگاری می باشند. در این شرایط با توجه به کاهش ریسک مخاطرات محیطی در طی سال های مختلف، پایداری عملکرد تا 4/28 درصد افزایش خواهد یافت.
    کلیدواژگان: افزایش دی اکسیدکربن، کاهش بارندگی، پایداری عملکرد، مدل نخود
  • ناصر جعفرزاده، علیرضا پیرزاد، هاشم هادی صفحات 182-196
    به منظور بررسی اثر تداخل تاج خروس ریشه قرمز (Amaranthus retroflxus L.) بر شاخص های رشد کرچک (Ricinus communis L.) و اندازه گیری عکس العمل تاج خروس از نظر تجمع وزن خشک و سطح برگ در رقابت با کرچک آزمایشی به صورت فاکتوریل در قالب طرح بلوک-های کامل تصادفی در شهرستان ارومیه در سال 91-1390 با سه تکرار اجرا شد. آزمایش شامل دو فاکتور تراکم کاشت کرچک در پنج سطح (صفر، سه، چهار، پنج و شش بوته در مترمربع) و تراکم تاج خروس در چهار سطح (صفر، پنج، 10 و 15 بوته در مترمربع) بود. نتایج تجزیه رشد نشان داد که حداکثر تولید ماده خشک، شاخص سطح برگ، سرعت رشد محصول و سرعت رشد نسبی در هر چهار تراکم کرچک مربوط به کشت خالص بود که با افزایش تراکم تاج خروس از مقدار آن ها کاسته شد. حداکثر و حداقل شاخص سطح برگ کرچک در 1046 درجه روز رشد به ترتیب در تراکم شش بوته کشت خالص کرچک و تراکم سه بوته کرچک و 15 بوته تاج خروس برابر 06/4 و 90/0 به دست آمد. بیشترین و کمترین مقادیر سرعت رشد محصول در همان درجه روز رشد به ترتیب در تراکم پنج بوته کشت خالص کرچک و تراکم سه بوته و 15 بوته در مترمربع تاج خروس برابر با 317/0 و 114/0 گرم در مترمربع در درجه روز رشد مشاهده شد. نتایج اندازه گیری صفات تاج خروس حاکی از کاهش شاخص سطح برگ، تجمع ماده خشک، سرعت رشد و سرعت رشد نسبی تاج خروس در حضور کرچک بود و با افزایش تراکم کرچک کاهش بیشتری در این صفات ایجاد شد. به طوری که در بالاترین تراکم تاج خروس (15 بوته در مترمربع) افزایش تراکم کرچک به ترتیب 44، 40 و 134 درصد افت بیشتر در سطح برگ، ماده خشک و سرعت رشد تاج خروس ایجاد کرد.
    کلیدواژگان: تجمع ماده خشک، سرعت رشد محصول، سرعت رشد نسبی، شاخص سطح برگ
  • مژگان ویسی، حمید رحیمیان مشهدی، حسن علیزاده، مهدی مین باشی، مصطفی اویسی صفحات 197-211
    به منظور بررسی تاثیر عوامل اقلیمی و خاکی بر پراکنش علف های هرز مطالعه ای در 85 مزرعه گندم (Triticum aestivum L.) آبی بر اساس سطح زیر کشت این محصول در 11 شهرستان استان کرمانشاه طی سال های 91-1390 انجام شد. مجموعا 162 گونه علف هزر متعلق به 33 خانواده گیاهی در این مزارع شناسایی شد. با استفاده از آنالیز چند متغیره همبستگی کانونی (CCA)، ارتباط پراکنش گونه های علف هزر با عوامل خاک (pH، کلسیم، منیزیم، فسفر، نیتروژن، پتاسیم، سدیم، درصد رس، شن و سیلت در بافت خاک، ظرفیت تبادل کاتیونی خاک و هدایت الکتریکی) و عوامل اقلیمی بررسی شد. مولفه اول و دوم در سال 1391 بیش از 64% واریانس پراکنش گونه ها را تحت تاثیر فاکتورهای اقلیمی توصیف کردند. یولاف وحشی زمستانه (Avena ludoviciana Dur.)، چچم (Lolium rigidum Gaud.)، خردل وحشی (Sinapis arvensis L.) و علف قناری (Phalaris brachystacys Link.) در مناطقی از استان که درجه حرارت بالا و ارتفاع از سطح دریا پایینی داشتند، از پراکنش وسیعی برخوردار بودند. تبخیر زیاد باعث افزایش علف های هرز جودره (Hordeum spontaneum C. Koch.)، بی تی راخ (Galium tricornutum Dandy.) و ماشک مریوانی (Vicia assyriaca Boiss.) طی ده ساله اخیر شد. خاک های با میزان نیتروژن و فسفر بالا، از جمعیت بالای علف هزر جودره در مزارع گندم برخوردار بودند. پیچک صحرایی (Convolvulus arvensis L.) و گلرنگ وحشی (Carthamus oxycantha M. B.) در خاک های رسی وفور بیشتری داشتند. تراکم بی تی راخ در خاک های قلیایی و شنی بیشتر از مناطق دیگر بود.
    کلیدواژگان: آنالیز همبستگی کانونی (CCA)، تبخیر، فراوانی
  • نسیبه پورقاسمیان، روح الله مرادی صفحات 212-226
    شاخص های تنوع زیستی ابزاری نیرومند برای ارزیابی پایداری نظام های کشاورزی محسوب می شوند. در این تحقیق که به منظور ارزیابی تنوع زیستی محصولات زراعی و باغی شهرستان های استان اصفهان و همچنین بررسی روابط موجود بین تنوع زیستی و عوامل اقلیمی این استان صورت گرفت، سطح زیر کشت، غنای گونه ای، یکنواختی، تنوع گونه ای و تنوع آلفا و بتای محصولات زراعی و باغی محاسبه شده و مورد ارزیابی قرار گرفتند. بدین منظور، اطلاعات مربوط به سطح زیر کشت گیاهان زراعی و باغی شهرستان های مختلف استان اصفهان در سال زراعی 92-1391 از طریق اطلاعات سازمان جهاد کشاورزی استان و همچنین پرسشنامه هایی جمع آوری گردید. محصولات زراعی به هشت گروه غلات، حبوبات، جالیزی، سبزیجات، علوفه ای، صنعتی و دارویی و محصولات باغی به دو گروه درختان میوه معتدله و گرمسیری طبقه بندی شدند. تنوع آلفا و بتا نیز با استفاده از رابطه غنای گونه ای مساحت برای اقلیم های مختلف استان محاسبه شد. نتایج نشان داد که در گروه محصولات باغی، درختان میوه معتدله (2/76 درصد) بیشترین و در گروه محصولات زراعی غلات (36/59 درصد) و گیاهان دارویی (09/1 درصد) به ترتیب بیشترین و کمترین سطح زیر کشت را دارا هستند. شهرستان های سمیرم و برخوار و میمه به ترتیب بیشترین و کمترین سطح زیر کشت محصولات باغی را به خود اختصاص دادند. بیشترین سطح زیر کشت محصولات زراعی در شهرستان اصفهان و کمترین آن در شهرستان خوروبیابانک مشاهده شد. شهرستان-های کاشان، لنجان، و نطنز با 17 گونه گیاهی، بیشترین و آران و بیدگل با سه گونه گیاهی کمترین غنای گونه ای محصولات باغی استان را در برداشتند. بیشترین و کمترین شاخص یکنواختی محصولات باغی به ترتیب مربوط به شهرستان های اصفهان (83/0) و سمیرم (192/0) بود. شهرستان های فلاورجان، خمینی شهر، کاشان، نایین و نجف آباد دارای بیشترین شاخص یکنواختی در محصولات زراعی و شهرستان اصفهان کمترین میزان این شاخص را نشان داد. به طور میانگین بیشترین و کمترین شاخص تنوع زیستی شانون- وینر در محصولات زراعی به ترتیب مربوط به گیاهان علوفه ای (929/0) و جالیزی (442/0) بود. این شاخص برای درختان معتدله بیش از دو برابر درختان گرمسیری گزارش شد. بیشترین و کمترین میزان تنوع آلفا به ترتیب در شهرستان های واقع در اقلیم های معتدل و بیابانی گرم مشاهده شد. اقلیم بیابانی معتدل نیز بالاترین میزان تنوع بتا را شامل شد.
    کلیدواژگان: تنوع آلفا، تنوع بتا، شاخص شانون، شاخص یکنواختی، غنای گونه ای
  • حمدالله اسکندری، اشرف عالی زاده امرایی صفحات 227-240
    برای ارزیابی اثر کشت مخلوط افزایشی ذرت (Zea mays L.) و لوبیا چشم بلبلی (Vigna Sinensis L.) بر وزن خشک و ترکیب گونه ای علف های هرز، یک آزمایش مزرعه ای در شمال خوزستان در سال زراعی 93-1392 انجام گرفت. آزمایش در قالب طرح پایه بلوک های کامل تصادفی در سه تکرار پیاده شد به طوری که ذرت و لوبیا چشم بلبلی در دو تیمار کشت خالص و چهار تیمار کشت مخلوط شامل شامل T1: 100 درصد تراکم کشت خالص ذرت+ 25 درصد کشت خالص لوبیا چشم بلبلی، T2: 100 درصد تراکم کشت خالص ذرت+ 50 درصد کشت خالص لوبیا چشم بلبلی، T3: 100 درصد تراکم کشت خالص ذرت+ 75 درصد تراکم کشت خالص لوبیا چشم بلبلی و T4: 100 درصد تراکم کشت خالص ذرت+ 100 درصد کشت خالص لوبیا چشم بلبلی کشت شدند. نتایج آزمایش نشان داد که شاخص مجموع عملکرد نسبی در کلیه تیمارهای کشت مخلوط بیشتر از یک بود که این امر حاکی از رابطه مکملی ذرت و لوبیا چشم بلبلی در مصرف منابع محیطی از جمله نور و رطوبت می باشد. به عبارت دیگر کاهش منابع محیطی در دسترس، وزن خشک علف های هرز را در سیستم های کشت مخلوط کاهش داد به طوری که از پنج گونه علف هرز ثبت شده در طول آزمایش، وزن خشک چهار گونه شامل تاج خروس (Amaranthus retroflexus L.) ، سوروف (Echinochloa cruss-gali L.)، خرفه (Portulaca oleraceae L.) و تاجریزی (Solanum nigrum L.) در کشت مخلوط در مقایسه با کشت خالص ذرت و لوبیا چشم بلبلی کاهش یافت. شاخص کارآیی خفه کنندگی علف های هرز نشان داد که در کشت های مخلوط نسبت به کشت خالص ذرت 36-21 درصد و نسبت به کشت خالص لوبیا چشم بلبلی 42-28 از وزن علف های هرز کاسته شد که نشان می دهد کشت مخلوط ذرت و لوبیا چشم بلبلی باعث کاهش رشد علف های هرز در مقایسه با کشت خالص می شود.
    کلیدواژگان: تراکم، کارآیی خفه کنندگی علف هرز، کشت خالص، مجموع عملکرد نسبی، مصرف منابع محیطی
  • حسام سجادی نیاکی، محمد تقی درزی، محمدرضا حاج سید هادی صفحات 241-250
    به منظور بررسی اثر ورمی کمپوست و کود بیولوژیک نیتروکسین بر کمیت و کیفیت اسانس گیاه دارویی بادرشبی (Dracocephalum moldavica L.)، شامل میزان اسانس و درصد ژرانیال، ژرانیل استات، نرال، ژرانیول و نریل استات در اسانس، آزمایشی به صورت فاکتوریل دو عاملی شامل ورمی کمپوست (صفر، پنج و 10 تن در هکتار) و کود بیولوژیک نیتروکسین (تلقیح و عدم تلقیح با بذر) در قالب طرح پایه بلوک های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی شرکت کشاورزی ران در شهرستان فیروزکوه در سال 1392 انجام گرفت. نتایج حاصل از این پژوهش نشان داد که بیشترین میزان اسانس (128/0 درصد) در مصرف پنج تن ورمی کمپوست و بیشترین درصد ژرانیل استات در اسانس (02/31 درصد) با مصرف 10 تن ورمی کمپوست حاصل گردید. کود بیولوژیک نیتروکسین دارای تاثیر معنی داری فقط بر روی درصد ژرانیل استات در اسانس بود، به طوری که بیشترین درصد ژرانیل استات در اسانس (40/30 درصد) در تیمار مصرف نیتروکسین (تلقیح با بذر) به دست آمد. همچنین اثرات متقابل در بین عامل ها بر روی میزان اسانس و درصد ژرانیل استات، ژرانیول و نریل استات در اسانس، معنی دار گردید به طوری که بیشترین میزان اسانس (167/0 درصد) و نریل استات در اسانس (36/2 درصد) در تیمار پنج تن ورمی کمپوست و عدم مصرف نیتروکسین و نیز بیشترین درصد ژرانیل استات (71/35 درصد) و کمترین درصد ژرانیول (79/4 درصد) در اسانس در تیمار 10 تن ورمی کمپوست و مصرف نیتروکسین حاصل گردید. طبق نتایج حاصله، بیشترین کمیت اسانس در تیمار پنج تن ورمی کمپوست و عدم مصرف نیتروکسین و بیشترین کیفیت اسانس در تیمار 10 تن ورمی کمپوست و مصرف نیتروکسین به دست آمد.
    کلیدواژگان: ژرانیل استات، ژرانیال، فیروزکوه، کود آلی
  • عاطفه بیانی، لیلی ابوالحسنی، ناصر شاهنوشی صفحات 251-262
    این پژوهش جهت بررسی جریان انرژی و انتشار گاز گلخانه ای دی اکسیدکربن در واحدهای پرورش سنتی گاوهای شیری در استان مازندران اجرا شد. اطلاعات از طریق تکمیل پرسشنامه و مصاحبه حضوری با 26 گاودار در سال 1393 جمع آوری شد. نتایج نشان داد که مجموع انرژی های ورودی برای تولید یک لیتر شیر 745/27 مگاژول بوده است. دو نهاده خوراک دام و سوخت به ترتیب با 4/47 و 5/28 درصد، پرمصرف ترین نهاده های انرژی بودند. کارایی انرژی در مقایسه با بهترین حالت مصرف انرژی که مقدار ارزشی آن عدد یک است و نشان دهنده شرایطی است که حداکثر بهره برداری از انرژی وارد شده به سیستم صورت می گیرد، 257/0 به دست آمد. سهم انرژی های تجدیدپذیر و تجدیدناپذیر در تولید یک لیتر شیر به ترتیب 2/48 و 8/51 درصد محاسبه شد. مجموع گازهای گلخانه ای (شامل N2O ،CH4 ،CO2) که به دلیل تولید الکتریسیته و استفاده از ماشین آلات منتشر می شود، 622/0 کیلوگرم دی اکسیدکربن به ازای تولید یک لیتر شیر محاسبه شد. در بین نهاده های مورد بررسی، دو نهاده ماشین ها و تجهیزات و سوخت به ترتیب با 3/72 و 7/25 درصد، بیشترین انتشار گازهای گلخانه ای را در تولید شیر داشتند. با توجه به یافته ها جایگزین نمودن نهاده های کم مصرف انرژی به جای نهاده های پرمصرف انرژی با نوشتن اصول جیره نویسی صحیح به طوری که افت عملکرد و کاهش بهره وری در خروجی واحدها مشاهده نشود، پیشنهاد می شود. همچنین، با توجه به این که ماشین آلات و سوخت بالاترین میزان انتشار گازهای گلخانه ای را به خود اختصاص داده، می توان با جایگزین نمودن ماشین آلات با مصرف گاز طبیعی با ماشین آلات با سوخت دیزل از طرفی مقدار انرژی کم تری برای تولید یک لیتر شیر صرف نمود و از طرف دیگر آثار سوء زیست محیطی را به کمترین مقدار خود رساند.
    کلیدواژگان: بهره وری، ستاده، کارایی انرژی و نهاده
  • اسماعیل رضایی چیانه صفحات 263-280
    به منظور ارزیابی برخی صفات کمی و کیفی سیاهدانه (Nigella sativa L.) و ریحان (Ocimum basilicum L.) در الگوهای مختلف کشت مخلوط با لوبیا (Phaseolus vulgaris L.) و نسبت برابری زمین، آزمایشی به صورت طرح بلوک های کامل تصادفی با هشت تیمار و سه تکرار در مزرعه ای واقع در استان آذربایجان غربی- شهرستان نقده در سال زراعی 93-1392 اجرا شد. الگوهای کاشت در هشت سطح شامل کشت مخلوط ردیفی (یک ردیف سیاهدانه + یک ردیف لوبیا + یک ردیف ریحان) و کشت مخلوط نواری (یک ردیف سیاهدانه + دو ردیف لوبیا + یک ردیف ریحان، دو ردیف سیاهدانه + چهار ردیف لوبیا + دو ردیف ریحان، سه ردیف سیاهدانه + شش ردیف لوبیا + سه ردیف ریحان، چهار ردیف سیاهدانه + هشت ردیف لوبیا + چهار ردیف ریحان) و کشت خالص سه گونه بود. صفات مورد آزمایش شامل عملکرد دانه، عملکرد بیولوژیک و درصد اسانس سیاهدانه، عملکرد ماده خشک و درصد اسانس ریحان در چین اول و دوم و عملکرد دانه و بیولوژیک لوبیا بود. نتایج نشان داد که عملکرد اقتصادی هر سه گیاه تحت تاثیر تیمارهای آزمایش قرار گرفت و میانگین این صفت در کشت خالص نسبت به کشت مخلوط بالاتر بود. با افزایش عرض نوارها در تیمار های کشت مخلوط عملکرد دانه سیاهدانه 30 درصد و عملکرد ماده خشک ریحان در چین اول 29 و در چین دوم 24 درصد نسبت به تیمار کشت خالص کاهش یافت، ولی نتایج در مورد گیاه لوبیا نشان داد که بین کشت خالص با کشت مخلوط چهار ردیف سیاهدانه + هشت ردیف لوبیا + چهار ردیف ریحان از نظر عملکرد دانه و عملکرد بیولوژیک اختلاف معنی داری وجود نداشت. درصد اسانس سیاهدانه و ریحان در تمامی تیمار های کشت مخلوط بالاتر از تیمار کشت خالص بود. بیشترین نسبت برابری زمین (93/1) از کشت مخلوط نواری با نسبت دو ردیف سیاهدانه + چهار ردیف لوبیا + دو ردیف ریحان به دست آمد که نشان دهنده افزایش سودمندی زراعی کشت مخلوط نسبت به کشت خالص است. به نظر می رسد که این الگوی کشت می تواند در افزایش درآمد اقتصادی و بهره وری استفاده از زمین های کشاورزی به ویژه در بوم نظام های تولید گیاهان دارویی به طور قابل ملاحظه ای موثر باشد.
    کلیدواژگان: اسانس، چندکشتی، عملکرد اقتصادی، کشاورزی پایدار، گیاهان دارویی
  • حسین کاظمی، پریسا علیزاده، علی نهبندانی صفحات 281-295
    تجزیه و تحلیل انرژی یک بوم نظام زراعی به منظور دستیابی به تولید پایدار ضروری است. در این بررسی جریان انرژی در دو سامانه زراعی گندم آبی و دیم تحت دو نظام خاکورزی در شهرستان شهرکرد در سال 1392 با استفاده از پرسشنامه و مصاحبه با کشاورزان برآورد و مقایسه گردید. این مطالعه در قالب طرح کاملا تصادفی با چهار مدیریت (کشت دیم بدون خاکورزی و با خاکورزی، کشت آبی بدون خاکورزی و با خاکورزی) اجرا شد، که در آن 10 مزارع در هر مدیریت به عنوان تکرار در نظر گرفته شد. در این تحقیق شاخص های کارایی انرژی، بهره وری انرژی، انرژی خالص، انرژی ویژه، انرژی مستقیم و غیرمستقیم و انرژی تجدیدپذیر و غیر تجدیدپذیر محاسبه شدند. نتایج حاصل از تجزیه و تحلیل داده ها نشان داد که حداکثر انرژی ورودی مربوط به سامانه کشت آبی با خاکورزی (معادل 29586 مگاژول در هکتار) و حداکثر انرژی خروجی در سامانه کشت آبی بدون خاکورزی (معادل 70743 مگاژول در هکتار) بود. بیشترین (43/2) و کمترین (03/1) کارایی مصرف انرژی در بخش دانه، به ترتیب مربوط به مدیریت کشت آبی بدون خاکورزی و دیم با خاکورزی بود. همچنین بیشترین انرژی مصرفی گندم آبی در هر دو سامانه بدون خاکورزی و با خاکورزی به ترتیب مربوط به کود نیتروژن (9429 و 1092 مگاژول در هکتار) و بعد از آن به آبیاری (8323 و 5117 مگاژول در هکتار) تعلق داشت و برای گندم دیم نیز بیشترین انرژی مصرفی به ترتیب در دو سامانه با خاکورزی و بدون خاکورزی مربوط به کود نیتروژن (8529 و 7220 مگاژول در هکتار) و بذر (4367 و 2412 مگاژول در هکتار) محاسبه شد. در هر دو مزارع آبی و دیم روش های بدون خاکورزی، دارای انرژی غیرمستقیم و غیر تجدیدپذیر بیشتری نسبت به روش های دارای خاکورزی بودند. به طور کلی از نظر شاخص های جریان انرژی، بهترین سامانه کشت در این منطقه مربوط به کشت آبی با روش بدون خاکورزی بود. بنابراین جهت کاهش مصرف منابع انرژی تجدیدناپذیر در منطقه مورد مطالعه، کاهش مصرف کودهای شیمیایی از جمله نیتروژن از طریق مدیریت بهینه کود، قرار دادن بقولات در تناوب زراعی، استفاده از کود سبز، استفاده از کود دامی و آلی و نیز مدیریت صحیح آب آبیاری توصیه می شود.
    کلیدواژگان: انرژی تجدیدپذیر و تجدیدناپذیر، انرژی مستقیم و غیرمستقیم، کارایی انرژی
  • راحله احمدزاده قویدل، قربانعلی اسدی، محمد تقی ناصری پور یزدی، رضا قربانی، سرور خرم دل صفحات 296-317
    به منظور ارزیابی روند تغییرات شاخص های فیزیولوژیک رشدی ارقام لوبیا (Phaseolus vulgaris L.) تحت تاثیر تراکم های مختلف بوته و مقادیر کود دامی، آزمایشی به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با 36 تیمار و سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد در سال زراعی 94-1393 انجام شد. فاکتور های مورد مطالعه شامل چهار رقم لوبیای قرمز (اختر، لاین 81083-D، ناز و گلی)، سه تراکم بوته (13/13، 20 و 40 بوته در مترمربع) و سه سطح کود گاوی کاملا پوسیده (صفر، 15 و 30 تن در هکتار) بود. شاخص-های رشدی مورد بررسی شامل شاخص سطح برگ، میزان تجمع ماده خشک، سرعت رشد محصول و سرعت رشد نسبی ارقام لوبیا قرمز در سطوح مختلف تراکم و کود دامی بود. نتایج نشان داد که بیشترین تجمع ماده خشک با 4/315 گرم در مترمربع برای رقم گلی و کمترین مقدار آن با 5/214 گرم در مترمربع در رقم اختر مشاهده شد. بالاترین شاخص سطح برگ (59/2) با مصرف 30 تن در هکتار کود دامی در رقم گلی به دست آمد. در هر چهار رقم حداکثر سرعت رشد محصول در 42 روز پس از سبز شدن و در تراکم 40 بوته در مترمربع حاصل شد و با کاهش تراکم به 13/13 بوته در مترمربع سرعت رشد محصول 18 درصد کاهش یافت. همچنین در تراکم 40 بوته در مترمربع بالاترین سرعت رشد نسبی نیز مشاهده شد.
    کلیدواژگان: سرعت رشد نسبی، شاخص سطح برگ، شاخص فیزیولوژیک رشد، کود گاوی
  • سید محمد سید ی، پرویز رضوانی مقدم صفحات 318-328
    بیماری پوسیدگی ریزوپوسی و نقطه سیاه از مهم ترین بیماری های انباری در گوجه فرنگی می باشند. به منظور بررسی توانایی چند گیاه دارویی بر ماندگاری و کنترل قارچ های عامل پوسیدگی انباری Rhizopus nigricans) و Alternaria alternate) در گوجه فرنگی های تولید شده در سامانه های کشاورزی رایج و زیستی، آزمایشی به صورت فاکتوریل در قالب طرح کاملا تصادفی با 14 تیمار و سه تکرار در دانشگاه فردوسی مشهد در سال 1389 اجرا شد. دو سامانه تولید شامل گوجه فرنگی رایج و زیستی (ارگانیک) و شش گونه گیاهی (آویشن (Thymus vulgaris L.)، پونه (Mentha pulegium L.)، نعناع فلفلی (Mentha piperita L.)، اکالیپتوس (Eucalyptus globules L.)، کرچک (Ricinus communis L.) و گوجه فرنگی (Lycopersicom esculentum Mill.)) به همراه تیمار شاهد به ترتیب عامل اول و دوم در این آزمایش بودند. بر اساس نتایج آزمون غیر پارامتری کروسکال– والیس، تفاوت معنی داری بین سامانه های تولید گوجه فرنگی های ارگانیک با نوع غیرارگانیک آن از نظر سرعت پوسیدگی انباری ناشی از رشد قارچ های بیماری زا مشاهده شد. به طوری که در گوجه فرنگی های ارگانیک، سرعت پوسیدگی (47/1 عدد میوه در هفته) تا حدود 20 درصد کمتر از نوع غیرارگانیک آن بود. نتایج حاصل از آنالیز غیرپارامتری گونه های گیاهی نیز حاکی از وجود تفاوت بین این گونه ها از نظر تاثیر بر سرعت پوسیدگی انباری در گوجه فرنگی بود؛ به طوری که به جز کرچک و گوجه فرنگی، سایر گیاهان دارویی منجر به کاهش معنی دار سرعت رشد و توسعه قارچ های بیماری زا در انبار شدند.
    کلیدواژگان: اکالیپتوس، آویشن، پونه، سرعت پوسیدگی، کرچک
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  • A. Koocheki, L. Tabrizi, M. Keikhah Akhar, A. Roohi Pages 153-168
    Introduction
    During the last decades interest in organic production of seed specially for medicinal plants take into consideration because of higher quality of organic products (Hermes, 2010). Seed germination is one of the principal stages in the plant life cycle and seeds with higher quality and vigour resulted in more pronounced seedlings growth and development. Therefore, investigation of agronomic practices specially nutrient management in the field is important because of its effective role in the promotion of plant growth, yield and consequently seeds with good quality criteria.
    Materials And Methods
    In order to investigate seed quantitative and qualitative criteria of black cumin (Nigella sativa L.), isabgol (Plantago ovate Forsk.) and fennel (Foeniculum vulgare Mill.) under application of organic fertilizers including cow manure, spent mushroom compost, municipal waste compost and control, an experiment was conducted in a complete randomized block design with three replications at Agricultural Research Station of Ferdowsi University of Mashhad, during two growing season of 2010-2011 and 2011-2012. Consequently, their seed quality criteria were evaluated in a factorial experiment based on completely randomized design with three replications in Laboratory of Seed Technology at College of Agriculture and Natural Resources, University of Tehran. Criteria such as biological and seed yield, harvest index, 1000- seed weight, length, width and diameter of seed, seed germination percentage and rate, seed vigour index, length and weight of seedling were investigated.
    Results And Discussion
    Results indicated that organic fertilizers caused a significant increase in seed yield and biological yield in which spent mushroom compost had the highest effect on mentioned criteria compared to control in both years of experiment. Harvest index was not affected by fertilizers in isabgol and black cumin in both years while showing a significant effect in fennel. Application of spent mushroom composts in the first year of experiment and municipal waste compost in the second year of the experiment affected 1000- seed weight of isabgol and black cumin, respectively. Also, seed germination percentage and rate, seedling length and weight and seed vigour index were affected by organic fertilizers in three studied species, in which cow manure performed better and caused the highest amount of seed criteria compared to control. Based on the results, application of cow manure, spent mushroom compost and municipal waste compost resulted in an increase of 43.75, 26.62 and 10.3 % in seed vigour index in comparison with control, respectively. Non-application of organic fertilizers caused 23.5, 17.66 and 8.48% reduction of mean seedling length compared to using cow manure, spent mushroom compost and municipal waste compost, respectively. Also, seedling dry weight had a similar trend like seedling length. Interaction effect of species and organic inputs affected seed length significantly, in which, spent mushroom compost caused the highest amount of seed length in studied species. Fennel seeds by using spent mushroom compost showed the highest seed length (6.19 mm) among different studied species and organic inputs. It seems black cumin, isabgol and fennel under organic nutrition showed more pronounce growth and yield in which resulted in production of seeds with higher vigour and germination criteria. Probably adequate balance of nutrients in seeds caused better growth of seedlings and consequently increased their length and dry weight compared to non application of organic fertilizers.
    Conclusion
    In general, the results of this experiment revealed that application of organic fertilizers such as cow manure, spent mushroom compost, municipal waste compost promoted both yield and seed quality characteristics of three studied species, black cumin, isabgol and fennel, which seems a promising result in production of organic medicinal plants.
    Acknowledgments
    This project was supported by the fund provided by the vice chancellor for research and technology of Ferdowsi University of Mashhad for which the authorsare thankful.
    Keywords: Compost, Germination rate, Harvest index, Manure, Seed vigour index
  • Amir Hajarpoor, Nassim Meghdadi, Afshin Soltani, Behnam Kamkar Pages 169-181
    Introduction
    Chickpea (Cicer arietinum L.) is cultivated on alarge scale in arid and semiarid environments. Terminal drought and heat stress, among other abiotic and biotic stresses, are the major constraints of yield in most regions of chickpea production. The study of the effects of climate change could help to develop adaptation strategies to promote and stabilize crop yield. This research was aimed to assess adoption strategies in rainfed chickpea in response to Zanjan province’s climate change using a crop simulation model along with providing simulated yield maps using geographical information system (GIS).
    Materials And Methods
    To study the effects of climate change and simulation the adaptation strategies, the model of Soltani and Sinclair (Soltani & Sinclair, 2011) was used. This model simulates phenological development, leaf development and senescence, mass partitioning, plant nitrogen balance, yield formation and soil water balance. For each location, a baseline period of daily weather data was available (Table 1). Investigated scenarios were historical climate (control) and future climate scenarios that included both direct effects of doubling CO2 (350 to 700 ppm) and its indirect effects (10% reduced rainfall, 4ºC increase in temperature). The crop model was performed for the different years of baseline period for current and future climate under typical management and cultivar and also under three adaptation strategies in the future climate including Management adaptation (M), Genetic adaptation (G) and a combination of both Management and Genetic adaptation (M & G) as described below (Table 2): Management – In various studies changing the planting dates as the simplest and least-cost adaptation strategy has been emphasized (Luo et al., 2009); hence a shift in planting dates i.e. sowing 15 days in advance was explored in this study to reduce the risk of the late season drought.
    Genetics – Changes in genotype have been suggested to be the most promising adaptation option in the world. Earlier maturity cultivars may be needed to match future drier conditions. Thus alternative genotype was a cultivar with 20% lesser of the required biological day from emergence to flowering.
    M & G – The third adaptation practice was an attempt to combine both earliness and early sowing date (15 days).
    A randomized complete-block design was used for data analysis in which climate condition with considered treatment and years was considered as blocks. When it was necessary, mean comparison was done using a Least Significant Difference (LSD) procedure at 5% level.
    Results And Discussion
    The results showed that in future climatic change, mean yield for Zanjan province will reach to 1036 kg.ha-1 with 38.4% increasing which was statistically different compared to current situation (760 kg.ha-1). The possibilities for gathering more benefits of grain yield were tested by changing traditional management and genetics of the locations in the future climate which involved three management options as adaptation strategies (Earlier Sowing, Earlier maturity Cultivars and combination of these two options). Applying earlier sowing date in comparison with conventional sowing date, increased mean yield by 67.7% (1268 kg.ha-1). In addition, applied earlier maturity cultivar led to 1212 kg.ha-1 (63.9% increase in comparison with current cultivar). Results revealed that using earlier maturity cultivars in combination with earlier sowing date will increase mean yield up to 1452 kg.ha-1 (94.5% increase),whichwasthe consequence of a shift in growing season to a wetter part of the year and reduced the risk of late season drought stress. Furthermore, breeding for earliness by reducing the vegetative period would save more water to be used for grain filling. Under these circumstances, according to decreased environmental risks, yield sustainability will increase up to 28.4%.
    Conclusion
    The Results of this study can also be extended to water-limited regions of chickpea producing with similar climatic and edaphic conditions. New varieties should be released with shorter growth periods than current ones and their sowing dates must be advanced if possible. Other management practices such as conservation tillage or keeping residue on the soil surface in order to save and increase soil water content were not included in this study which is suggested to evaluate the effects of these factors on the yield of crops in the future climate change studies.
    Keywords: Chickpea model, Doubling CO2 concentration, Reducing rainfall, Yield stability
  • Naser Jafarzadeh, Alireza Pirzad, Hashem Hadi Pages 182-196
    Introduction
    Growth analysis has been widely used in breeding programs to identify the important plant developmental phases and components related to higher yield under a particular set of environmental conditions. Castor bean (Ricinus communis L.) is an important commercial crop. Castor oil based by products is used in manufacturing of several commercially important commodities like surfactants, coatings, greases, pharmaceuticals, cosmetics, polyesters, polymers, etc. Interference (Interactive effects among species on inter-species populations) 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 (Shinggu et al. , 2011). Growth indices are useful for interpreting plant reactions to the crop and weed density. Various reasons have been attributed for the low productivity among the most important is weed competition (Radosevich, 1987). The aim of the present experiment was evaluating the interference effects of redroot pigweed on growth indices of castor bean in northwest of Iran.
    Materials And Methods
    This experiment was conducted in Urmia, Iran (Agricultural Research of West Azarbayjan, Saatlo Station (37°44´18״ N Latitude and 45° 10´ 53״ E Longitude, at 1338 m above sea level) ) in 2012. The soil of the experimental field was sandy - loam, with pH of 7. 2. Competitive pattern of experiment was in two-factor based on a randomized complete block design (RCBD) with three replications arranged in four castor plant densities (3, 4, 5 and 6 plants. m-2) and four redroot pigweed densities (0, 5, 10 and 15 plants. m-2). Redroot pigweed and castor seeds were simultaneously directly planted on the 22th May in 2012. Redroot pigweed plants were weeded at the times related to the treatments level. Irrigation and intercultural operations were performed whenever necessary. Plots were 3m×5m with 60 cm between rows. Seven times during plant growth stage castor plants were harvested from each plot considering marginal effects. The plants were transferred to the laboratory for evaluating of dry matter. Excel (Microsoft Office, 2007) was used for drawing of diagrams.
    Results And Discussion
    The results showed that the highest dry matter (DM), leaf area index (LAI), crop growth rate (CGR) and relative growth rate (RGR) of castor were observed in pure stands of castor. Among pure stands, the highest and the lowest DM and CGR were achieved in castor densities of 5 and 3 plants. m-2, respectively. The highest (4. 06) and lowest (0. 90) of castor LAI were observed in 6 plants. m-2 of castor density and 3 plants. m-2 of castor with 15 plants. m-2of pigweed at 1046 GDDs, respectively. The Maximum (0. 317 g. m-2. g. d. d-1) and minimum (0. 114 g. m-2. g. d. d-1) of crop growth rate for castor plants were achieved at the same GDDs in 5 plants. m-2 of castor, and 3 plants. m-2 of castor with 15 plants. m-2 of pigweed, respectively. These parameters were decreased by increasing pigweed densities. Therefore, it can be concluded that DM and CGR are decreased, due to increasing pigweed density; these parameters are slightly affected by castor density. Measurement results of pigweed characteristics indicated reduction in LAI, DM, Weed Rate Growth (WRG) and RGR of pigweed in presence of castor bean. Increasing in castor density caused a greater reduction in the mentioned characteristics whereas in the highest density of pigweed (15 plants. m-2), increasing in castor density caused 44, 40 and 134 % decrease in LAI, DM, WRG, respectively.
    Conclusion
    The results of this study showed that increasing plant density to 6 plant. m-2 increased LAI, DM, CGR and RGR. Therefore, it (6 plants. m-2 of Castor bean density) can be recommended for reducing redroot pigweed damage in Castor bean field.
    Acknowledgments
    The authors acknowledge the financial support of the project byVice President for Research and Technology, Urmia University, and West Azarbaijan Agricultural and Natural Resources Research Center, Iran.
    Keywords: Crop growth rate (CGR), Density, Leaf area index (LAI), Relative growth rate (RGR), Weed
  • Mozhgan Veisi, Hamid Rahimian, Hassan Alizade, Mehdi Minbashi, Mostafa Oveisi Pages 197-211
    Introduction
    Kermanshah province, Iran, comprises an area, of 24640 km2 and is located between 33°37′-35°17′N and 45°20′-48°1′E. The average annual precipitation is 450 mm. Most of the fields surveyed in this study lie between 542 and 1554 m a.s.l. Among the factors decreasing the wheat yields, weeds have an important role. The results of some researches show that the weeds flora depends on climatic conditions, temperature and amount of rainfall in spring and in summer. Environmental factor splay a key role in the weed cover. These differences affected by climatic conditions, latitude and longitude. Multivariate statistical methods that have been addressed in this study area powerful tool to study the relationship between environmental factors and ecological weed community composition (Hassannejad & Pourhaydar Ghafarbi, 2013; Lososova et al., 2004). Correlation and regression of data floristic and environmental factors were used in the CCA (Canonical Correspondence Analysis) technique (Legendre & Legendre, 1998).
    Materials And Methods
    A survey was conducted to study the effects of soil and climatic factors on distribution of weeds in 85 irrigated wheat fields in 11 counties based on its area under irrigated wheat. An Experiment was conducted in Kermanshah province during 2011-2012. After choosing the field to be surveyed, the surveyor followed a “w”-designated set pattern to enumerate the weeds in each type of field. The pattern and number of 0.25 m2 quadrats varied according to the size of the fields. The field surveys were made during the wheat tillering to stem elongation stages. Frequency, density and mean density index of species in each county were calculated. After weed species were collected in the fields, we arranged the samples into the first matrix where weed species are represented by columns and fields of different districts by rows. Also, in the second matrix, environmental factors are represented by columns and fields of different districts by rows. Data on weed communities and environmental factors of all districts were analyzed through with ordination methods like canonical correspondence analysis (CCA) and weed species distribution and environmental factors displayed in ordination diagrams. These ordination methods were done with mean density of 29 abundant weed species for CCA using CANOCO (Version 4.5). Ordination plots were produced for both sampling sites and weed species associated with environmental factors. For CCA, we used site elevation, humidity for 10 years period, daily raining for a 10 years period. Soil characteristic included calcium, phosphor, potassium, nitrogen, sodium, magnesium, pH were determined. Sand, clay and silt in soils were measured and elevation of each field was gained by GPS.
    Results And Discussion
    162 weed species belonging to 33 plant families were identified in these fields. Multivariate analyses with canonical correspondence analysis (CCA) showed that changes in the weed species distribution were due to soil characters (pH, Calcium, Magnesium, Phosphorus, Nitrogen, Sodium, Potassium, silt percent, clay and loam in soil tissue, cation exchange capacity, EC) and environmental conditions during former years. The first and second RDA axes described 64% of variations in the weed populations affected by climatic factors. Winter wild oat (Avena ludoviciana L.), ryegrass (Lolium rigidum Gaud.), wild mustard (Sinapis arvensis L.) and canary seed (Phalaris brachystacys Link.) in areas of high temperature and low altitude, had a wide distribution. High evaporation increased wild barely (Hordeum spontaneum C. Koch.), Corn cleavers (Galium tricornutum Dandy.) and Vetch (Vicia assyriaca Boiss.) density during last decade. Where the soil nitrogen and phosphorus rates were high, Wild barely (Hordeum spontaneum C. Koch.) density was found frequently in wheat fields of Kermanshah. In the wheat fields of Kermanshah, Bindweed (Convolvulus arvensis L.) and wild safflower (Carthamus oxyacantha M. B.) were more abundant in clay soils. High Corn cleaver (Galium tricornutum Dandy.) density was found in alkaloid and sandy soils.
    Conclusion
    Generally predict that if the temperature rise over the next few years, weed density and abundance of wild oat, ryegrass and wild mustard will be increased in irrigated wheat fields.
    Acknowledgments
    The authors acknowledge the financial support of the project by agricultural Research education and extension organization and College of Agriculture and Natural Resources, Tehran University.
    Keywords: Canonical correlation analysis (CCA), Evaporation, Frequency
  • Nasibe Pourghasemian, Rooholla Moradi Pages 212-226
    Introduction
    Agricultural biodiversity has spatial, temporal and scale dimensions especially at agro-ecosystem levels. These agro-ecosystems that are used for agriculture are determined by three sets of factors: the genetic resources (biodiversity), the physical environment and the human management practices. Most agricultural areas can be returned to their natural landscape after subsequent generations. Studies on spatial patterns of species diversity are fundamental to biological conservation. Agricultural biodiversity is essential to satisfy basic human needs for food and livelihood security and it is active lymanaged by farmers and many components need human interference (Maguran, 1996).
    FAO estimates that 75% of crop varieties have been lost during the last 100 years. One third of the 6.500 domestic livestock races are endangered. The genetic erosion of crops and livestocks threatens food security.
    Plant diversity of usually evaluated by many indexes of which Shannon index is the most important ones. This index in agroecosystem rarely exists. Koocheki et al. (2004) and Nassiri Mahallati et al. (2005) in comprehensive surveys evaluated agrobiodiversity of agricultural systems at species variety and cropping systems for Iran and they found that the diversity at all levels have been declining due to introduction of new agricultural technology. In consideration to the lack of studies, this study was conducted in order to evaluate the biodiversity of agronomical and horticultural productions in Isfahan province and to assess relation of biodiversity and climate.
    Materials And Methods
    This study was performed for Isfahan province in 2014. For this purpose, 24 regions of the province were selected. Planting area, species richness, species evenness and alpha and beta diversity of different agronomical and horticultural productions were determined. The information about agronomical and horticultural planting area for different regions of Isfahan was gathered. Agronomical crops were classified to seven groups; cereal, pulses, vegetable, forage, industrial crops and medicinal plants and horticultural plant classified into 2 groups; temperate and tropical fruits. The Shannon index was calculated based on the cultivated area as equation 1. For determination of distribution condition of the crops we used from evenness index. Alpha and beta diversity was calculated by spices richness- area equation for different climate of province.
    Results And Discussion
    The result showed that tropical fruits (76.2%) and cereal (59.36%) showed the highest planting area and medicinal plants (1.09%) were included the lowest planting area in Isfahan province. Semirom and Borkharomeymeh regions had the highest and lowest horticultural planting area, respectively. The highest planting area of agronomical products was observed in Isfahan and the lowest amount of the trait was gained in Khorobiabanak. The highest species richness in horticultural plants was in Kashan, Lenjan and Natanz (17 species) regions and the lowest was obtained in Aranobidgol (with three species) regions, respectively. This condition was in line with climate of the regions. Ardestan and Isfahan regions were contained the highest (29 species) and Khorobiabanak had the lowest (11 species) species richness of agronomical plants. The highest and lowest species evenness of horticultural productions was gained in Isfahan (0.83) and Semirom (0.192), respectively. Felavarjan, Khomeinishahr, Kashan, Nain and Najafabad regions had the highest and Isfahan region was contained the lowest species evenness of agronomical productions. Many study demonstrated that there is a positive and high correlation between species evenness and diversity. This condition was true for our study. The forage and vine crop showed the highest (0.929) and lowest (0.442) Shannon indices, respectively. The lowest and highest alpha diversity were observed in moderate and desert-hot climates, respectively. It because that the planted crop in moderate climate was higher than desert-hot climate. Desert-moderate climate was obtained the highest beta diversity.
    Conclusion
    The results showed that tropical fruits and cereal were content the main planting area and medicinal plants were included the lowest planting area of Isfahan. The highest species richness in horticultural plants was in Kashan, Lenjan and Natanz regions. Ardestan and Isfahan regions were contained the highest and Khorobiabanak had the lowest species richness of agronomical plants. The highest and lowest species evenness of horticultural productions was gained in Isfahan and Semirom, respectively. The lowest and highest alpha diversity was observed in moderate and desert-hot climates, respectively. Desert-moderate climate was obtained the highest beta diversity.
    Keywords: Alpha diversity, Beta diversity, Evenness index, Richness index, Shannon index
  • Hamdollah Eskandari, Ashraf Alizadeh, Amraie Pages 227-240
    Introduction
    Weeds are main factors reducing crops yield, especially under organic farming conditions (). It has been reported that weed populations are more in organic farming compared to conventional cropping systems, resulting in more reduction of growth and yield. Although the chemical control is a fast and effective way for controlling weed populations, some negative impacts of the recent weed management on public health and the natural environment, increased the concerns of using weed chemical compositions. Thus, non-chemical weed control is in high importance. Intercropping, an agronomical operation in which two or more crops are grown simultaneously in the same field, is one of the most important methods for increasing biodiversity in agricultural ecosystems (Amosse et al., 2013; Rostami et al., 2009; Yuan-Quan et al., 2012). Therefore, the current research was aimed to evaluate the possible non chemical controlling of weeds in a maize-cowpea intercropping system.
    Materials And Methods
    A field experiment was conducted in the north of Khuzestan during the growing season 2013-2014. The experiment was based on a randomized complete block design with three replications. Maize and cowpea were planted in two sole crop systems and four intercropping systems based on an additive series, including T1:100 percent maize percent cowpea, T2: 100 percent maize percent cowpea, T3: 100 percent maize percent cowpea and T4: 100 percent maize흍 percent cowpea. No chemical materials (fertilizer and pesticide) were used during growing season. Environmental usage by intercropping patterns was evaluated by measuring photosynthetically active radiations (PAR) (mean of five points in each plot, selected randomly) and soil moisture content at three stages. At harvest time, all plants of each plot were harvested and grouped and weighed according to their species type. Complementary effect of intercropping in using environmental resources was calculated using relative yield total (RYT) index. Weed smothering efficiency (WSE) was used to evaluate the effect of intercropping on reducing weeds the dry weight.
    Results And Discussion
    Results indicated that soil moisture content, PAR interception and soil temperature were affected by cropping patterns. The lowest and highest values of soil temperatures were observed in intercropping and sole crop systems, respectively. Intercropping systems exploited soil water more than sole crops. PAR interception was higher in intercropping compared to sole cropping. However, sole cowpea showed lower PAR interception compared to maize sole crop. Relative yield total (RYT) index was more than unity in all intercropping systems. Weed smothering efficiency (WSE) showed that dry weight of weeds was reduced by 21-26 and 28-42 percentages in intercropping systems compared to sole maize and sole cowpea cropping systems, respectively. The growth of weeds (in terms of total dry weight) in intercropping systems were reduced in which from five recorded weed species, the dry weight of them, including amaranth (Amaranthus retondus L.), pigweed (Echinocloa cruss-gali L.), purslane (Portulaca oleraceae L.) and Halikakabon (Solanum nigrum L.) decreased in intercropping compared to sole cropping systems. Intercropping components showed a complementary relation in consuming environmental resources including soil moisture and PAR. Since the soil temperature was lower in intercropping compared to sole cropping, lower soil moisture in intercropping cannot be resulted from higher evaporation in intercropping, but also the widespread root system in intercropping resulted in higher efficiency in soil moisture consuming. Relative yield total more than unity, showing the advantages of intercropping in environmental resources consumption. Soil covering and higher biodiversity are two main factors reducing weeds growth in intercropping because the two recent factors lower PAR availability for weeds which can reduce weed. The current research, taller maize absorbed incoming PAR and shorter cowpea intercepted PAR at ground surface, resulting in lower PAR for weeds. Higher plant populations in intercropping have been reported as a main factor for reducing environmental resources availability for weeds reducing their growth.
    Conclusion
    The Relative yield total was more than unity, indicating the complementarity of maize and cowpea in intercropping systems for environmental resources consumption which was resulted in lower weeds growth. Thus, intercropping can be used as a non-chemical method for weeds control.
    Keywords: Density, Environmental resource consumption, Relative yield total, Sole cropping, Weeds smothering efficiency
  • Hesam Sajadi Niaki, Mohammad Taghi Darzi, Mohammad Reza Haj Seyed Hadi Pages 241-250
    Introduction
    Dragonhead (Dracocephalum moldavica L.) is an annual herbaceous aromatic plant and belongs to Lamiaceae family. It is native to south of Siberia and Himalayan hillsides. The essential oil content shows great variation due to plant origin. The main constituents of dragonhead essential oil have been reported as geranial, geranyl acetate, neral and geraniol. Using organic manures and biofertilizers such as vermicompost and nitrogen fixing bacteria contain azotobacter and azospirillum has led to a decrease in the application of chemical fertilizers and has provided high quality agricultural products. Several studies have shown that organic and bio-fertilizers application such as vermicompost and Nitroxin can increase quantity and quality of essential oil of medicinal plants of dragonhead, anise and thyme (Darzi et al., 2013; Mafakheri et al., 2012; Mohammadpour Vashvaei et al., 2015). Therefore, the main objective of the present field experiment was to investigate the effects of vermicompst and Nitroxin biofertilizer on quantity and quality of essential oil of dragonhead.
    Materials And Methods
    An experiment was conducted as afactorial experiment in the base of randomized complete blocks design with six treatments and three replications at research field of Agriculture Company of Ran in Firouzkuh of Iran in 2013. The factors were Vermicompost in three levels (0, 5 and 10 t.ha-1) and Nitroxinbiofertilizer (inoculated seeds and non-inoculated). Inoculation was carried out by immersing the dragonhead seeds in the cells suspension of 108 CFU/ml for 15 min. The required quantities of vermicompost were applied and incorporated to the top 5 cm layer of soil in the experimental beds before planting of dragonhead seeds. Each experimental plot was 3 m long and 2.28 m wide with the spacing of 10 cm between the plants and 38 cm between the rows. There was a space of one meter between the plots and 2 meters between replications. In this study, quantitative and qualitative traits of dragonhead essential oil content, granial percent, granyl acetate percent, neral percent, graniol percent and neryl acetate percent in essential oil were evaluated. For determine the essential oil content (%), about 100 g dried herb of dragonhead (dried in shadow) as sample from the each plot were selected and then were subjected to hydro-distillation (Clevenger type apparatus) for 2 till 3 hours. For identifying the essential oil components, essential oil fraction was collected and subjected to GC and GC/MS (gas chromatography and gas chromatography-mass spectrometry) analysis. Analysis of variance by using SAS software and mean comparisons by Duncan’s multiple range test (at the 5% probability level) was done.
    Results And Discussion
    The present resultsshow that the highest essential oil content in applying 5 t.ha-1 vermicompost and the maximum geranyl acetate in essential oil in applying 10 t.ha-1 vermicompost were obtained. Nitroxin biofertilizer showed significant effects on geranyl acetate in essential oil only, as the highest geranyl acetate were obtained by using the Nitroxin (inoculated seeds). Also, the intractions effect of factors on essential oil content, geranyl acetate, graniol and neryl acetate in essential oil were significant, as the highest essential oil content and neryl acetate percent at treatment of 5 t.ha-1 vermicompost and without application of Nitroxin and the maximum geranyl acetate and the lowest geraniol in essential oil at treatment of 10 t.ha-1 vermicompost and application of Nitroxin were obtained. According to the results of this study, the maximum essential oil quantity at treatment of 5 t.ha-1 vermicompost and without application of Nitroxin and the highest essential oil quality at treatment of 10 t.ha-1 vermicompost and application of Nitroxin were obtained.
    Conclusion
    Vermicompost application positively influenced on quantity and quality of essential oil dragonhead, as the highest essential oil content in treatment of application of 5 t.ha-1 vermicompost and the highest essential oil quality in treatment of integrated application of 10 t.ha-1 vermicompost and Nitroxin were obtained. On the base of research results, organic and bio-fertilizers application such as vermicompost and Nitroxin in a sustainable agriculture system can be caused in improvement of qualitative characters of dragonhead.
    Keywords: Firouzkuh, Geranial, Geranyl acetate, Organic fertilizer
  • Atefeh Bayani, Leili Abolhassani, Naser Shahnoushi Pages 251-262
    Introduction
    Energy is one of the most important commodities that make up a large proportion of international trade. Among all the countries in the world, Iran is known as semi-industrial developing country which is rich in energy such as non-renewable energy in particular fossil fuel. Use of energy affects the environment in various forms of pollution. In the agricultural sector, the FAO report states that livestock production has a major contribution to the world’s environmental problem (Sutton et al., 2011).
    Materials And Methods
    This study analyzes energy flow and greenhouse gas emission in conventional dairy farms in Mazandaran province. The required data for this study was collected by conducting interviews and filling up questionnaires from 26 cattlemen. From the questionnaires, information on five inputs such as labor, livestock feeding, diesel fuel, electricity and technical equipment and machines as well as milk product for 159 dairy cattle was collected. Finally, energy productivity, efficiency and emissions of greenhouse gases were calculated for Methane (CH4), Nitrous Oxid (N2O) and Carbon Dioxide (CO2).
    Results And Discussion
    The results indicated that total energy which has been used to produce one liter of milk was 27.745 Mega Jul. Livestock feeding and fuel were energy inputs that has been extensively consumed. In this relation, 47.4% and 28.5% of the total energy consumption were drawn from the livestock feeding and fuel, respectively. In the study conducted by Sainz (2003), livestock feeding with 70% of the total energy consumption was also found as the largest input in terms of consuming energy. Technical equipment with 22.8% of the total energy consumption was found the third place. A low proportion (0.8%) of the total energy consumption was drawn from labor. Electric power with 0.5% of the total energy consumption was placed at the last. Energy efficiency was measured at 0.257. The proportion of renewable and non-renewable energy in one-litter milk production was measured by 48.2% and 51.8%, respectively. The total greenhouse gas emitted toproduceone litter of milk is equal to 0.622 kg of carbon dioxide that is higher than the amount of carbon dioxide generated from dairy farms in the United States (Sainz, 2003), but lower than the amount produced by dairy farms in Portugal (Castanheira et al., 2010). For the European countries, the average of greenhouse gas emission generated from dairy farms was calculated about 0.45 carbon dioxide equivalent. Technical equipment, machines and fuel with generating 0.45 and 0.16 kg of carbon dioxide equivalent were the most contribution to greenhouse gas emission. According to the calculations, the two inputs emitted 72.3% and 25.7% of the total greenhouse gas emission in producing one litter of milk. Only 2% of the total greenhouse gas emission that is equal to 0.012 kg of carbon dioxide equivalent was created from electricity generation. In the United States, diesel fuel and electricity with a contribution of 27% to 40% of the total greenhouse gasemissions were realized as the most polluted inputs. Furthermore, in Ireland and Britain, the diesel fuel and electricity with producing 0.03 and 0.002 of carbon dioxide equivalent were realized as the most polluted inputs for producing one litter of milk. This suggests that diet re-formulation with special consideration to the output is an effective solution to the problem mentioned above. Considering technical equipment and fuel as the most pollutant inputs, transferring equipment from natural gas consumption to diesel consumption decreases both energy consumption and negative-environmental externalities.
    Conclusion
    Considering that the livestock feeding has the largest amount of energy consumption, thedairy cow feed formulation should be considered as the most important concern. In relation to diesel fuel, replacement of natural gas with diesel fuel can reduce greenhouse gas emissions at a large extend
    Keywords: Energy efficiency, Input, Output, Productivity
  • Esmaeil Rezaei, Chiyaneh Pages 263-280
    Introduction
    Cultivation of medicinal plants in agricultural ecosystems plays an important role in the diversification and sustainability of these systems (Rezaei-Chiyaneh & Dabbagh Mohammadi Nassab, 2014). Therefore, the application of ecological principles such as multi-ship system seems essential in the production of these plants. Zarifpour et al. (2014) in intercropping arrangements of cumin and chickpea showed that different cropping patterns had a significant effect on chickpea and cumin yield and the highest essential oil and land equivalent ratio achieved by planting ratio 50% cumin 50% chickpea. Therefore, the objectives of the present study were to examine the effect of different intercropping patterns of black cumin and basil with bean on their yield and qualitative traits.
    Materials And Methods
    In order to evaluate some quantitative and qualitative traits of black cumin (Nigella sativa L.) and basil (Ocimum basilicum L.) in different intercropping patterns with bean (Phaseolus vulgaris L.) and land use efficiency, a field experiment was conductedbased on a randomized complete block design with eight treatments and three replications at the farm located in West Azerbaijan province in Nagadeh, Iran during growing reason about 2013-2014. Cropping patterns included row intercropping (one row of black cumin one row of bean one row of basil) and strip intercropping (one row of black cumin two rows of bean one row of basil, two rows of black cumin four rows of bean two rows of basil, three rows of black cumin six rows of bean three rows of basil, four rows of black cumin eight rows of bean four rows of basil) and their solecropping.
    Black cumin was harvested when they turned brown, dried and shelled, and bean was harvested when the first pod of the plants fully matured and dried. Basil was harvested in the first and the second harvest at 50% of flowering.
    Land Equivalent Ratio (LER)
    Land equivalent ratio of basil, black cumin and bean was calculated using equation 1 (Koocheki et al., 2014): Equation 1: Where, Y1, Y2 and Y3 represent basil, black cumin and bean yield in intercropping, respectively and B1, B2 and B3 represent basil, black cumin and bean yield in solecropping, respectively.
    Results And Discussion
    Results revealedthat the economic yield of three plants was significantly affected by treatments and theaverage yield was higher in solecropping than intercropping. By increasing in strip width seed yield of black cumin, dry matter yield in the first,and the second harvest of basil were decreased 30, 29, and 24 percent, respectivelycompared to monoculture. However, seed yield and biological yield of bean did not indicate any significant differences at solecropping with four rows of black cumin eight rows of bean four rows of basil. Higher seed yield and biological yield of sole cropped may be due to the fewer disturbances in the habitat in homogeneous environment of monocropping systems. Moreover, no significant difference between sole cropping of bean with combinations of 4 rows black cumin 8 rows bean 4 rows basil may be due to facilitative interaction in this combination. The percentage of essential oil in black cumin and basil of all treatments was higher than solecropping. Higher essential oil yield in intercropped could be due to the positive effect of bean such as nitrogen fixation for black cumin and basil. The essential oil content of black cumin and basil are, furthermore, positively affected by intercropping with bean.The maximum land equivalent ratio (1.93) was obtained in two rows of black cumin four rows of bean two rows of basil that represents an increase advantages in intercropping than solecropping.
    Conclusion
    The results showed that quantitative and qualitative yield of three species was affected by planting ratio. The maximum seed and biological yield of three species were obtained at solecropping. The percentage of essential oil in black cumin and basil of all treatments were higher than solecropping. The LER index was higher than one in all intercropping treatments compared to solecropping systems. Generally,it seems that the cropping pattern “two rows of black cumin four rows of bean two rows of basil“ is remarkably effective to increase the economic income and land use efficiency.
    Keywords: Economic yield, Essential oil, Intercropping, Medicinal plants, Multicropping, Sustainable agriculture
  • Hossein Kazemi, Prisa Alizadeh, Ali Nehbandani Pages 281-295
    Introduction
    Energy analysis of agricultural ecosystem is essential for sustainable production. The relation between agriculture and energy is very close. Agriculture is an energy consumer and the energy supplier. Agriculture’s use of energy is recognized in three external inputs: labor, machines, and fertilizers (Connor et al., 2011). Significant gains in energy efficiency were arisen in agriculture following the phenomenal increase in energy prices in the 1970s. Greater use of diesel motors, larger tractors, using conservation tillage methods and optimized fertilizer use efficiency were the main causes (Ozkan et al., 2004). Safa & Samarasinghe (2013) were reported that fuel consumption in tillage and harvesting was more than other operations in wheat fields of Canterbury, New Zealand. Effective application of agricultural techniques and efficient use of support inputs can minimize environmental problems and in consequence promote sustainable agricultural intensification. In this study, the energy flow investigated in irrigated and rain-fed wheat cropping systems under two tillage and no-tillage methods in the Shahrekourd city, during 2013.
    Materials And Methods
    The study was carried out in the Sharekourd city (Chaharmahal Bakhteyari province). This region is located within 32º 20' and 32º 21' Lat. N, 50º 48' and 50º 50' Lon. E. Data were collected from 40 farmers with questionnaire method. In this study, a randomized complete design with four scenarios (rain-fed and irrigated farming with tillage and no-tillage systems) was used, that 10 farms were considered as a replication in each scenario. All data detail information on the questionnaire were averaged and arranged. First, all inputs and outputs of wheat production were determined, quantified and entered into Microsoft Excel spreadsheets, and then transformed into energy units and expressed in MJ.ha-1. Based on the total energy equivalents of the inputs and output and the energy use efficiency (energy ratio), net energy, energy productivity and specific energy were calculated. The input energy was divided into direct, indirect, renewable and non-renewable forms. Indirect energy included energy embodied in seed, fertilizers, chemicals, machinery; while direct energy covered human labor, water for irrigation, electricity and diesel fuel were used in the wheat production. The LSD test (P≤0.05) was used to compare means between all scenarios.
    Results And Discussion
    The results of data analysis indicated that maximum input energy was about 29,586 MJ.ha-1 in the irrigated fields under tillage and maximum output energy was about 70,743 MJ.ha-1 in the irrigated fields under no-till. In this study, the highest and lowest energy efficiency were obtained in irrigated system under no-tillage (2.43 in seed) and rain-fed system under tillage (1.03 in seed), respectively. The greatest contribution from total energy belonged to energy of nitrogen fertilizer (9,429 MJ.ha-1 in no-tillage and 1,092 MJ.ha-1 in tillage systems) and irrigation (8,323 MJ.ha-1 in no-tillage and 5,117 MJ.ha-1 in tillage systems) in irrigated cropping system and nitrogen fertilizer (8,529 MJ.ha-1 in no-tillage and 7,220 MJ.ha-1 in tillage systems) and seed (4,367 MJ.ha-1 in no-tillage and 2,412 MJ.ha-1 in tillage systems) in rain-fedfarming system. Therefore, it is necessary to focus more on nitrogen fertilizer consumption than the other factors to effectively reduce energy consumption in wheat cropping. In addition, the no-tillage system had high indirect and non-renewable energy forms in both wheat cropping systems. The high ratio of non-renewable energy in the total used energy inputs cause negative effects on the sustainability in agroecosystems.
    Conclusion
    Generally, irrigated cropping system under no-tillage method was the best condition for wheat production in Shahrekourdcity. The results revealed that there was a huge potential toimproveenergy efficiency of wheat production in this region. Furthermore, toreducenon-renewable energy use in the studied region, we recommended the use of chemical fertilizer specially nitrogen reduce by appropriate management of fertilizer, use of legume in crop rotation, use of green manure, organic fertilizer and manure.
    Acknowledgements
    We are grateful to Agriculture Service Centers of Shahrekourd and Gorgan University of Agricultural Sciences and Natural Resources (GUASNR).
    Keywords: Energy efficiency, Direct, indirect energy, Renewable, non, renewable energy
  • Raheleh Ahmadzadeh Ghavidel, Ghorbanali Asadi, Mohammad Taghi Naseri Pour Yazdi, Reza Ghorbani, Surur Khorramdel Pages 296-317
    Introduction
    Legumes after cereals are the second source of human food and in Iran they are the second most important food after the wheat. Legumes protein is four times as much as that of grains and 10 to 20 times as much as that of glandular plants. In addition, beans are planted in Iran in a wide area and knowing optimal farming factors can be an important step in increasing them.
    One of the most important factors determining the yield of cowpea (Vign asinensis L.) is appropriate plant density. Plant density defines the number of plants per square meter, which in turn determines the area available to each individual plant. For most crops, plant density has a major influence on biomass, crop yield and economic profitability.
    In common bean (Phaseolus vulgaris L.), plant density can affect canopy architecture, light conversion efficiency, duration of vegetative growth, dry matter production, seed yield and ultimately, the economic productivity of a crop. Therefore, optimizing plant density, which may be defined by both the number of plants per unit area and the arrangement of plants on the ground, is a pre-requisite for obtaining higher productivity of common bean. However, the other yield components such as number and weight of pods and seeds per plant and 100- seed weight which are established at a later stage in the course of the crop cycle are significantly affected by environmental conditions. Furthermore, the contribution efficiency of these components in the final seed yield is also associated with the number of plants per unit area. Therefore, varying plant density may be a viable alternative to manipulate the productivity of bean under different environmental conditions through their changes in physiological processes. Madani et al. (2008) showed that plant density had significant effect on LAI and shoot dry weight of bean. Moeinit et al. (2009) reported the increase in common bean seed yield with the increase in plant density. Another important factor determining growth indices is manure. Integrated supply of nutrient to plants through planned combinations of organic and inorganic sources is becoming an increasingly important aspect of environmentally sound agriculture. There are reports which show that the application of manure on bean has improved yield and growth indices.
    Materials And Methods
    In order to study the effects of plant density and cow manure levels on four common bean cultivars an experiment was conducted as a factorial arrangement based on complete randomized block design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad, during two growing seasons of 2011-2012 and 2013-2014. The experimental treatments were plant density in three levels (13.13, 20 and 40 plants.m-2), three cow manure levels (0, 15 and 30 kg.ha-1) and four common bean cultivars (Gholi, Akhtar, Naz and D-81083). The plot size was 5×2 meter and the spacing between rows was 50 cm and the seeds were planted in four rows. In order to measure the growth indices, the destructive samplings were carried out every 10 days from 50 cm of row in each plot. All common bean plants were harvested by cutting at the soil surface. Dry matter (DM), leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), net assimilation rate (NAR), of bean (Phaseolus vulgaris L.) were measured and calculated accordingly. Plants were then divided into leaf and stem. The areas of green leaves were measured using a Delta-T leaf area meter (Delta-T Devices, Cambridge, England). Then the samples, including stems and leaves were dried in a forced-air oven at 80 ˚C for 48 h and after witch total dry matter (TDM) was measured. The leaf area data was divided to ground area and the leaf area index (LAI) was obtained. The LAI data was fitted to the Gaussian equation (Equation 1) to predict the LAI of common bean in growth season: x (t)= a . Exp {-0.5((x-x0)/b) ^2} (Equation 1)
    Where is the time (day), x (t): predicted LAI; a, the maximum LAI during growth season; b is the time that after that the LAI increase exponentially; x0, the time (day) that common bean had the highest LAI.
    The sigmoid equation (Equation 2) was fitted to the TDM data and by derivation from this equation, the crop growth rate (CGR) (Equation 3) and relative growth rate (Equation 4) were obtained (Steinmaus and Norris, 2002): W (t) = a / 1 exp {-b (t-m)} (Equation 2)
    CGR = b. w (t) {1-(w (t)/a)} (Equation 3)
    RGR = b {1-(w (t)/a)} (Equation 4)
    Where t is the time (day), W(t), common bean dry matter at time t; a, the maximum total dry matter of common bean; b, the slope of increasing the dry matter; m, the time that common bean had the maximum growth rate and CGR is crop growth rate. The regression analysis was performed by SAS 9.1 and the graphs were prepared by Excel.
    Results And Discussion
    The results showed that during the days after planting in all treatments, leaf area index first increased until 56 days after planting and then it had a descending trend. The highest slope of leaf area increase is related to plant density (40 plants.m-2). Although, decreasing plant density from 40 plants.m-2 to 13.13 decreased LAI 29% plants.m-2. The results revealed that the maximum of LAI was obtained in cow manure (30 t.ha-1) (2.57). LAI for four common bean cultivars were different. The cultivar Goli with 2.61 had the greatest LAI. Crop growth rate (CGR) in all treatments first increased slightly and then increased more quickly until 56 days after planting. Then CGR decreased with a sharp slope. Gradual increase of CGR at first was due to insufficient vegetative meristems; however, as the plant canopy was completed and due to more efficient application of light and increase of leaf area the rate of CGR increased quickly so that it was maximized and then it decreased due to increase of interplant competition, decrease of light penetration into canopy photosynthetic organs’ getting late and also assimilates mobilization into grains. In this study the lowest rate of plant growth recorded during growth stage belonged to 13.13 plant.m-2 density, 0 t.ha-1cow manure and Akhtar cultivar) (8.32 g.m-2.day, 7.90 g.m-2.day and 4.26 g.m-2.day, respectively). Relative growth rate decreased as the plant age increased so that at the end of growth season RGR was close to zero. At the beginning of growth stage, due to more penetration of light into the canopy and less shadow of the leaves on each other and the less respiration, RGR is more and its reduction slope is less. As time passes and vegetative and reproductive organs grow more, the shadow of leaves on each other increases and RGR decreases. Plant density with 40 plants.m-2 shows the highest primary RGR and the plant density with 3.13 plants.m-2 shows the lowest one. The highest RGR in the 56th day has been related to 30 t.ha-1cow manure.
    Conclusion
    We can conclude that indeterminate common bean cultivars such as Goli and Naz showed the greatest growth rate and these findings indicate that the common bean (Phaseolus vulgaris L.) crop has the ability to alter plant size and canopy structure in response to changes in plant density. These strategies can be used as cultural methods to reduce the competitive ability of weeds and maintain common bean growth at acceptable levels. However, there is a need to evaluate numerous common bean cultivars in different locations and years to find cultivars with high competitive ability and stability in yield.
    Acknowledgments
    The authors acknowledge the financial support of the project by Vice President for Research and Technology, Ferdowsi University of Mashhad, Iran.
    Keywords: Competitive ability, Dry matter, Leaf area index, Relative growth rate
  • S.M. Seyyedi, P. Rezvani Moghaddam Pages 318-328
    Introduction
    After crops harvesting, conditions and durations of storage are considered as the most crucial factors formaintaining the nutritional value and quality of agro-horticultural products such as tomato (Lycopersicom esculentum Mill.) and its waste reduction. However, the rhizopus rot (Rhizopus stolonifer) and black spot rot (Alternaria alternate) are the most important postharvest diseases in tomato during storage. In other word, among the factors reducing quality of the postharvest tomato, Rhizopus nigricans Ehrenb. (Rhizopus stolonifer) and Alternaria alternate (Fr.:Fr.) Keissl. f. sp. lycopersici paly a special role in the contaminated tomato fruits that can affect its taste, firmness and stiffness.
    In recent years, due to the problems and threats arising from the use of chemical fungicides in agricultural systems, principled management of alternative biological approaches for reducing the postharvest contamination in tomato, especially during storage, is emphasized more than ever.
    Considering these conditions, the current study was aimed to investigate the effects of some medicinal plants including thyme (Thymus vulgaris L.), pennyroyal (Mentha pulegium L.), peppermint (Mentha piperita L.), eucalyptus (Eucalyptus globules L.), caster bean (Ricinus communis L.) and tomato in their ability to control the rhizopus (Rhizopus nigricans) and black spot rot (Alternaria alternate) in tomato production under conventional and organic cropping systems.
    Materials And Methods
    The experiment was conducted at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during theyear of 2010. A completely randomized design was used based on factorial arrangement with three replications and 14 treatments. Two cropping production systems (conventional and organic) and seven medicinal plants (thyme, pennyroyal, peppermint, eucalyptus, caster bean, tomato and control) were the first and the second experimental factors, respectively.
    After collecting plant samples from the research farm of Ferdowsi University of Mashhad, each sample was separately placed in cardboard package and then was transferred to governesses. By observing the disease sign during storage, the tomato fruits were graded based on the severity of postharvest diseases (the rhizopus and black spot rot) on tomato as follow: First- grade (no disease), second- grade (observation of very low disease sign in fruits), third- grade (observation of low disease sign in fruits, low watery fruits), fourth- grade (observation of disease sign in one third of surface fruits, moderate watery fruits), and fifth- grade (observation of disease sign more than one third of surface fruits, high watery fruits).
    For statistical analysis, non-parametric Kruskal-Wallis test were performed using MINITAB software.
    Results And Discussion
    Based on Kruskal-Wallis nonparametric test, organic and conventional cropping systems had different effects on storage- rot rate of tomato. In organic cropping systems, storage- rot rate (1.48 fruit per week) significantly decreased by 20%, compared to conventional cropping systems. In this regard, it has been reported that the soil fertility and applying organic fertilizer based on implementing organic farming systems has an important role in increasing the durability, nutritional value and quality of postharvest tomatoes.
    According to the results, medicinal plants had significant effects on storage- rot rate in tomato. Results indicated that the medicinal plants significantly reduced storage rhizopus and black spot rot in tomato, except caster bean and tomato. Among the treatments, peppermint and pennyroyal considered as the most effective plants in reducing the storage- rot rate and increasing the rigid and healthy fruits; so that the use of these plants in a tomato packing significantly decreased the storage- rot rate by 21%, compared to control treatment.
    As it can be seen from the results, a significant decrease in symptoms of fungal diseases and an increase in the number of healthy postharvest fruits due to application of mentioned plants can demonstrate the ability of these plants in reducing the activity of fungal pathogens during tomato storage. In line with the results, Feng & Zheng (2007) reported that the application of essential oil of thyme can play an effective role in controlling growth of fungal pathogens in tomato through reducing sporesgermination ability.
    Conclusion
    In conclusion, the results underlined the role of organic systems in improving the quality of postharvest tomatoes, compared with conventional systems. Moreover, for controlling the fungal pathogens, bio-products derived from medicinal plants can be especially considered in line with processing the postharvest tomatoes.
    Keywords: Caster bean, Eucalyptus, Pennyroyal, Rot rate, Thyme