فهرست مطالب

پژوهش های کاربردی زراعی - پیاپی 116 (پاییز 1396)

نشریه پژوهش های کاربردی زراعی
پیاپی 116 (پاییز 1396)

  • تاریخ انتشار: 1396/09/30
  • تعداد عناوین: 6
|
  • فرزاد فنودی *، حمیدرضا خزاعی، محمد کافی، مرتضی گلدانی صفحات 1-10
    به منظور بررسی اندازه گیری تاثیر سطوح نیتروژن بر تغییرات کارایی مصرف نیتروژن و عملکرد در ارقام قدیم و جدید جو آزمایشی بصورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با 3 تکرار در مشهد و دامغان در سال زراعی 1394-1393 انجام شد. تیمارهای آزمایش از ترکیب سطوح مختلف عامل رقم (شامل 5 رقم جدید: فجر30، نصرت، بهرخ، یوسف، نیک و 5 رقم قدیم: ریحان، ارم، افضل، نیمروز، کارون) در سطوح مختلف عامل کود نیتروژنه (3 سطح کود نیتروژن شامل مصرف کود نرمال، 50 درصد کمتر و 50 درصد بیشتر از مقدار نیتروژن توصیه شده) بدست آمد. در این پژوهش صفات عملکرد دانه، کارایی مصرف نیتروژن، کارایی جذب نیتروژن، کارایی بهره وری نیتروژن، شاخص برداشت نیتروژن، نیتروژن بذر اندازه گیری شدند. تجزیه واریانس مرکب مشاهدات نشان داد که اثر کود نیتروژنه و رقم برای تمامی صفات مورد مطالعه کاملا معنی دار می باشد، اثرمتقابل مکان در رقم برای صفات کارایی مصرف نیتروژن، کارایی بهره وری نیتروژن و عملکرد معنی دار و سایر اثرات متقابل معنی دار نشد. مقایسه میانگین نشان داد ارقام جدید کارایی مصرف نیتروژن و عملکرد بالاتری نسبت به ارقام قدیمی دارند. تمام صفات مورد مطالعه ارتباط مثبت و معنی داری با عملکرد دانه نشان دادند. با توجه به برتری ارقام جدید نسبت به ارقام قدیم از لحاظ عملکرد و کارایی مصرف نیتروژن در هر دو منطقه، استفاده از ارقام جدید برای کشت مطلوب تر است اما با توجه به عکس العمل متفاوت ارقام در مناطق مشهد و دامغان بایستی برای هر منطقه رقم پایدار انتخاب گردد.
    کلیدواژگان: عملکرد، کارایی جذب نیتروژن، تجزیه مرکب، ارقام جدید
  • محمدحسین انصاری *، هادی اسدی رحمانی صفحات 10-20
    به منظور ارزیابی اثر سطوح مختلف کود نیتروژن و کمپوست قارچ بر عملکرد، اجزای عملکرد و جذب نیتروژن، فسفر و پتاسیم لوبیا تحت تلقیح با باکتری های آزوسپریلوم و ازتوباکتر، آزمایشی به صورت فاکتوریل در قالب طرح بلوک کامل تصادفی با سه تکرار در منطقه رشت اجرا شد. فاکتورهای آزمایش شامل سطوح مختلف کود نیتروژن (0، 75 و 150 کیلوگرم اوره در هکتار) و تیمارهای غیر شیمیایی (باکتری آزوسپریلوم، باکتری ازتوباکتر، کمپوست قارچ (2 تن در هکتار)، کمپوست قارچ + آزوسپریلوم، کمپوست قارچ + ازتوباکتر و شاهد) بودند. نتایج آزمایش نشان داد که در هر سه سطح کود نیتروژن تیمارهای غیر شیمیایی مقدار کلروفیل برگ، تعداد غلاف در بوته، تعداد دانه در بوته و عملکرد بیولوژیک را به طور معنی دار نسبت به شاهد افزایش دادند. همچنین تیمارهای غیرشیمیایی در سطح صفر، 75 و 150 کیلوگرم نیتروژن، عملکرد دانه را به ترتیب 19 تا 63، 10 تا 74 و 5 تا 65 درصد نسبت به شاهد افزایش دادند و بیشترین عملکرد دانه (3067 کیلوگرم در هکتار) از تیمار آزوسپریلوم + کمپوست قارچ در سطح 75 کیلوگرم کود نیتروژن به دست آمد. در اغلب تیمارهای غیرشیمیایی، با افزایش مصرف کود نیتروژن، غلظت نیتروژن و فسفر اندام هوایی و دانه و غلظت پتاسیم دانه کاهش یافت، ضمن آن که تیمار آزوسپریلوم + کمپوست قارچ نسبت به سایر تیمارها برتری معنی دار داشت. بنابراین برای افزایش عملکرد و کیفیت دانه لوبیا کاربرد کمپوست قارچ و 75 کیلوگرم در هکتار اوره تحت تلقیح با باکتری آزوسپریلوم در منطقه رشت توصیه می شود.
    کلیدواژگان: باکتری محرک رشد گیاه، پتاسیم، پروتئین، فسفر، کلروفیل، کود آلی
  • غلامحسین شیر اسماعیلی *، علی اکبر مقصودی مود، غلامرضا خواجویی نژاد، روح الله عبدالشاهی صفحات 30-50
    نوسانات بارندگی و دسترسی به منابع آب زیرزمینی در مناطق خشک و نیمه خشک، عملکرد و اجزای عملکرد محصولات زراعی را به ویژه در کشت های بهاره و تابستانه تحت تاثیر قرار می دهد. گل رنگ یکی از گیاهان روغنی بومی ایران است که نسبت به خشکی مقاوم است. این آزمایش به صورت کرت های دو بار خردشده و در قالب طرح بلوک های کامل تصادفی با چهار تکرار اجرا شد. فاکتور اصلی شامل دو تاریخ کشت بهاره و تابستانه، فاکتور فرعی شامل سه تیمار آبیاری (شاهد، قطع آبیاری در شروع گلدهی و قطع آبیاری از دوره پر شدن دانه) و فاکتور فرعی فرعی شامل نه رقم گلرنگ بود. تاریخ کاشت بهاره نسبت به تابستانه در تمامی صفت های اندازه گیری شده اختلاف معنی دار داشت. عملکرد دانه در تاریخ کشت فروردین ماه 3070 کیلوگرم در هکتار بود که نسبت به تیرماه، 62 درصد افزایش نشان داد. تیمار آبیاری بر ارتفاع، تعداد دانه در غوزه و عملکرد دانه اثر معنی دار داشت و قطع آبیاری باعث کاهش تعداد دانه در غوزه و عملکرد گردید. عملکرد دانه در تیمارهای آبیاری در دوره پر شدن دانه و دوره گلدهی نسبت به تیمار شاهد به ترتیب 21 و 54 درصد کاهش نشان داد. در بین ارقام، صفه و گلدشت دارای بالاترین عملکرد دانه بودند و در تیمار قطع آبیاری در شروع گلدهی بین ارقام اختلاف معنی داری مشاهده نشد. به طورکلی رقم های ایرانی نسبت به ارقام مکزیکی توانایی بهتری برای مقاومت به تنش و تولید عملکرد دانه بالاتر داشتند.
    کلیدواژگان: زمان کاشت، تنش آب، دانه روغنی، عملکرد دانه، تعداد غوزه
  • علی جلیلیان *، فردین حامدی، عادل نعمتی، مهیار شیخ الاسلامی، پیمان ثابتی، فرشاد زندیان صفحات 50-60
    به منظور بررسی اثرات مقادیر مختلف ورمی کمپوست بر عملکرد وکیفیت چغندرقند(رقم اکباتان) آزمایشی در سال 1392در قالب طرح بلوکهای کامل تصادفی با چهار تکرار و 11 تیماردر ایستگاه تحقیقاتی ماهیدشت کرمانشاه اجرا شد. تیمارها شامل نسبت های مختلفی از مقادیر 3، 5 و 7 تن ورمی کمپوست با کودهای شیمیایی (اوره، سولفات پتاسیم و سوپر فسفات تریپل به ترتیب 400 ، 215 و 240 کیلو گرم در هکتار) به همراه شاهد بود که قبل از کاشت با دیسک با خاک مخلوط شد. نتایج نشان داد که تر کیبی از مصرف ورمی کمپوست و کودشیمیایی بیشترین عملکرد و کیفیت را در چغندرقند ایجاد می کند. به طوریکه بیشترین عملکرد ریشه درتیمارهای با مصرف 3 تا 7 تن ورمی کمپوست بعلاوه مقدار 50 درصد کودهای شیمیایی توصیه شده با 57.4 تا 59.7 تن در هکتار بود و کمترین عملکرد مربوط به تیمارهای مصرف ورمی کمپوست و بدون کود شیمیایی با عملکرد 42.6 تا 45تن در هکتار بدست بود. از نظر کیفیت و درصد قند تفاوتی بین تیمارها مشاهده نشد. نتایج تحلیل اقتصادی اثر مصرف کودها نشان داد که هیچ کدام از تیمار های اعمال شده نسبت به شاهد(مصرف 100 درصد کود شیمیایی توصیه شده) از نظر اقتصادی برتری نداشت. در مجموع با در نظر گرفتن سایر مزایای بلند مدت مصرف ورمی کمپوست و مسائل زیست محیطی مصرف 3 تا 5 تن در هکتار ورمی کمپوست بعلاوه 50 درصد کود شیمیائی مورد نیاز در زراعت چغندرقند قابل توصیه می باشد.
    کلیدواژگان: ورمی کمپوست، کود شیمیایی، چغندرقند، عملکرد
  • سیدعلی پیغمبری *، حمیدرضا بابایی، هادی علی پور صفحات 70-80
    ارزیابی تنوع ژنتیکی و شناسایی ژنوتیپ های با پتانسل عملکردی بالا و محتمل به تنش های محیطی می تواند در پیشبرد برنامه های به نژادی آتی بسیار ارزشمند باشد. بنابراین به منظور ارزیابی تنوع ژنتیکی و تحمل به تنش کم آبی، تعداد 40 ژنوتیپ متوسط رس سویا از گروه رسیدن III و IV انتخاب و در قالب طرح بلوک های کامل تصادفی با سه تکرار تحت شرایط آبیاری نرمال و تنش کم آبی در مزرعه تحقیقاتی بخش دانه های روغنی موسسه اصلاح و تهیه نهال و بذر در سال زراعی 1393 کشت شدند. تحت شرایط آبیاری نرمال و تنش کم آبی، صفات عملکرد دانه، تعداد دانه در بوته و تعداد شاخه های فرعی نه تنها ضریب تغییرات فنوتیپی و ژنتیکی بالایی نشان دادند، بلکه توارث پذیری و پیشرفت ژنتیکی بالایی نیز داشتند. براساس نتایج نمودار بای پلات، ژنوتیپ های L6-P79، Chaleston×Mostang/12، D42×Will82، D42.I4، Spry×Savoy/3، D42.I9 و DI-74 از نظر عامل های مربوط به عملکرد و اجزای عملکرد تحت شرایط آبیاری نرمال و تنش کم آبی مقادیر بالایی نشان دادند که می توان از آنها به عنوان ژنوتیپ های با عملکرد بالا تحت شرایط آبیاری نرمال و تنش کم آبی یاد کرد. البته ژنوتیپ های D42×Will82 و Chaleston×Mostang/12 با وجود اینکه تحت شرایط آبیاری نرمال و تنش کم آبی عملکرد بالایی نشان دادند ولی کاهش عملکرد نسبتا بالایی تحت شرایط تنش کم آبی نشان دادند. بنابراین با وجود حساسیت نسبی این ژنوتیپ ها به تنش کم آبی، می توان از آنها برای کشت در مناطقی که امکان وقوع تنش کم آبی نیز وجود دارد، استفاده نمود.
    کلیدواژگان: تنش کم آبی، تنوع ژنتیکی، صفات فنولوژیک، عملکرد و اجزای عملکرد
  • حمید جباری *، نیراعظم خوش خلق سیما، امیر حسین شیرانی راد صفحات 90-100
    این آزمایش به صورت کرت های یکبار خرد شده در قالب طرح بلوک های کامل تصادفی با سه تکرار در منطقه یزد در سال زراعی 1391-1390 انجام شد. تیمارهای آبیاری شامل شاهد (آبیاری براساس 80 میلی متر تبخیر از سطح تشتک تبخیر کلاس A) و تنش خشکی (قطع آبیاری از مراحل 50 درصد ساقه دهی، گل دهی و خورجین دهی به بعد) و ارقام شامل سه رقم کلزای پاییزه (GKH2005، Operaو Okapi) بودند که به ترتیب در کرت های اصلی و فرعی قرار گرفتند. نتایج نشان داد که میزان اسید اولئیک روغن دانه کلزا در محدوده 64 تا 68 درصد و اسید لینولئیک در محدوده 15 تا 18 درصد متغیر بود. در بین سه اسید چرب اشباع (پالمتیک، استئاریک و آراشیدیک)، اثر آبیاری بر اسید آراشیدیک و اسید استئاریک و در بین شش اسید چرب غیر اشباع (پالمیتولئیک، اولئیک، لینولئیک، لینولنیک، گادولئیک و اروسیک)، تنها بر اسیدهای چرب اولئیک، لینولئیک و لینولنیک معنی دار بود. قطع آبیاری از مراحل نموی سبب افزایش معنی دار اسید اولئیک در مقایسه با تیمار شاهد شد، درحالی که مقدار اسید لینولئیک کاهش چشمگیری یافت. واکنش سه رقم کلزا از نظر اسید چرب لینولئیک به سطوح آبیاری متفاوت بود و در سطوح قطع آبیاری رقم GKH2005از بیشترین میران اسید لینولئیک برخوردار بود. بیشترین عملکرد دانه در بین ارقام مورد بررسی در رقم GKH2005و به میزان 2211 کیلوگرم در هکتار مشاهده شد و به طور کلی این رقم با برخورداری از عملکرد دانه بیشتر و کیفیت مناسب اسیدهای چرب روغن دانه در شرایط تنش خشکی برتر از سایر ارقام بود.
    کلیدواژگان: اسید اولئیک، اسید لینولئیک، اسید لینولنیک و عملکرد دانه
|
  • Farzad Fanoodi *, Hamid Reza Khazaei, Mohammad Kafi, Morteza Goldani Pages 1-10
    Introduction
    Barely (Hordeum Vulgare L.) is one of the major grain crops from cereal family, which is the world`s fourth most important crop in terms of cultivation area and yield production after wheat, corn and rice. Iran`s share of world barely production is 2.7 million hectares, representing almost 1.86 % of total global barley production, according to Ministry of Agriculture Jihad statistics (2013). Nitrogen is one of the most important nutritional elements with a high consumption rate, which plays a pivotal role in the vital processes of plants. Lack of nitrogen is associated with the more significant limitation in producing crops compared to the other natural elements. Over-consumption of nitrogen fertilizer harms the environment, while it also has an intense restrictive effect on microorganism diversity and yield of the crops’ roots. Furthermore, less consumption of nitrogen than the required amount might be associated with the diminished yield of the crops (Beatty et al., 2010). To increase the efficiency of nitrogen consumption, we need nitrogen management strategies, traditional methods of plant breeding and biotechnology. The aim of this study was to evaluate the effects of different levels of nitrogen fertilizer on nitrogen use efficiency and yield of old and new barely cultivars in the two regions of Mashhad and Damghan.
    Materials And Methods
    The study was conducted at the research farms of Ferdowsi University of Mashhad and university of Agricultural Sciences of Damghan, Iran in the crop year of 2014-2015, using a factorial design based on completely random blocks with three replicas. Experimental treatments were combination of barley cultivars (five new cultivars: Fajr 30, Nosrat, Behrokh, Yousef and Nik, and five old cultivars: Reyhan, Eram, Afzal, Nimrooz and Karoon) and different levels of nitrogen fertilizer based on soil test from depth of 0-30 cm (the consumption of normal fertilizer, 50% less and 50% more than the recommended amount of nitrogen for barely). In this experiment, in addition to yield attributes, traits such as nitrogen use efficiency, nitrogen uptake efficiency, nitrogen productivity, nitrogen harvest index and seed nitrogen content were measured.
    Result and
    Discussion
    The results of combined analysis of variance indicated that the effect of nitrogen fertilizer and cultivar was significant on the all studied traits. While the interaction of the location and cultivar was significant for nitrogen use efficiency, nitrogen productivity and yield, the other interactions were not found to be significant. The lower application of nitrogen than normal was compared with its excessive consumption, which indicated a reduction in the nitrogen utilization efficiency, uptake efficiency, productivity, harvest index, and nitrogen seed content in all the studied barely cultivars. The new barely cultivars exhibited higher nitrogen use efficiency than the old cultivars. Furthermore, maximum and minimum nitrogen use efficiency were respectively recorded for Behrokh cultivar at Mashhad region and Afzal cultivar at Damghan region, where nitrogen use efficiency of new cultivar of Behrokh was 57 % more than that of Afzal old cultivar. Accordingly, level of nitrogen use efficiency under the climate of Mashhad was approximately 33% higher than Damghan. The highest nitrogen uptake efficiency and harvest index were observed in Behrokh and Eram cultivars, respectively. In addition, maximum and minimum content of nitrogen in the seeds were registered for the cultivars of Nik and Afzal, respectively, so that the seed nitrogen content of Nik new cultivar was 22% higher than Afzal old cultivar. Comparison of average grain yield across the regions showed that the old cultivars consistently produced lower grain yield as compared to new ones where Yousef new cultivar gave the highest grain yield (6573 kg ha-1) in Mashhad and old Afzal cultivar had the lowest grain yield (3152 kg ha-1) in Damghan. Superiority of new cultivars compared to old cultivars could be attributed to their genetic enhancement in terms of yield production (Gabriella et al., 2003). It is also notable that all the studied features in the current research had significant positive associations with seed yield performance. Given the variable response of the cultivars in Mashhad and Damghan, different cultivars should be tested to identify those cultivars that are adapted to the climatic conditions of each region.
    Keywords: New Cultivars, Composite Analysis, Function, Nitrogen Utilization Efficiency
  • Mohammmad Hossein Ansari *, Hadi Asadi Rahmani Pages 10-20
    Introduction
    The common bean (Phaseolus vulgaris L.) is an important crop both in temperate and tropical climates and is an excellent source of protein. It is well established that depletion in nitrogen availability strongly affects rhizobial populations in the rhizosphere of legumes (Padilla et al., 2015). Nitrogen (N) is a major nutrient for plant growth and development and affects the seed yield more than other nutrients. Excessive application of nitrogen fertilizer increases nitrogen loss through leaching (water contamination) and sublimation (air pollution) (Zaidi et al., 2017). Biological fertilizers, which are a mixture of microorganisms, can be partial substitutes for chemical fertilizers. The ability of several bacterial species such as Azospirillum and Azotobacter in providing a large portion of the plant’s demanded nitrogen through biological fixation has been proven. Also, mushroom compost, which is one of the side–products of the edible fungus industry, can play an important role in increasing plant nitrogen uptake as a quality modifier. The present study is based on the assumption that the application of mushroom compost and biofertilizers can improve, in addition to seed yield, the seed quality of bean as compared to chemical nitrogen.
    Material and
    Methods
    A field experiment was conducted in Rasht, North of Iran, as factorial based on a randomized complete blocks design with three replications during the grown season 2015. The experimental factors consisted of chemical nitrogen (0, 75 and 150 kg urea ha–1) and biological treatments (Azospirillum lipoferum, Azotobacter chroococcum, mushroom compost (2 t ha–1), mushroom compost Azospirillum, mushroom compost Azotobacter and a control). A local cultivar of bean "Pach Baghala” which was obtained from Guilan Agricultural and Natural Resources Research and Education Center was used in this experiment. The measured traits included chlorophyll content, the concentration of N and phosphorus (P) (root, shoot and seed) and potassium (K) of seed, yield components and seed yield. The statistical analysis was conducted using the SAS 9.2 software.
    Results And Discussion
    The results showed that inoculation of the bean plant with the biological agents under all levels of chemical nitrogen fertilizer increased leaf chlorophyll content, number of pods per plant, number of seeds per plant and biological yield as compared to the control. Also, the application of biological treatments in the presence of 0, 75 and 150 kg of nitrogen raised bean seed yield by 19 – 63%, 10 – 74% and 5 – 65%, respectively, and the highest seed yield (3067 kg ha–1) was obtained from Azospirillum mushroom compost treatment at 75 kg nitrogen ha–1. Almost all the biological treatments used in this study led to decreased N and P concentrations of seed and shoot and K concentration of seed with increasing nitrogen fertilizer and the highest shoot N (3.82%), seed protein (30.93%), seed P (1.880%), seed K (1.96%) and protein yield (950 kg ha–1) were observed with Azospirillum mushroom compost treatment. We found that when the bacteria, especially Azotobacter, were applied individually, they did not have a pronounced effect on the most of the traits of bean, but when used simultaneously with mushroom compost, they significantly augmented the plant nutrient uptake and seed yield. The Azospirillum, both individually and in combination with compost resulted in more bean N and P uptake, biological and seed yield than Azotobacter. Under the inoculation of biological agents, bean plant, when supplied with 150 kg nitrogen ha-1, produced yield which was less than or equal to 75 kg nitrogen ha-1. Therefore, the use of mushroom compost in combination with biofertilizers can reduce the requirement of chemical nitrogen fertilizer by up to 50%. The use of growth promoting bacteria can induce greater allocation of dry matter to different plant organs, which may result in increased vegetative development, making it possible for plant to capture more light and consequently increase its photosynthetic rate, ultimately leading to enhanced grain yield (Chauhan and Bagyaraj, 2015)
    Conclusion
    According to our results, application of Azospirillum mushroom compost (2 t ha-1) under 75 kg nitrogen ha-1 can be considered as one of the suitable treatments for obtaining the highest seed yield and quality in common bean in Rasht region.
    Keywords: Chlorophyll, Organic fertilizer, PGPR, Phosphorus, Potassium, Protein
  • Gholamhosein Shir Esmaeili *, Aliakbar Maghsoudi Mood, Gholamreza Khajouei Nezhad, Rouhollah Abdolshahi Pages 30-50
    Introduction
    Safflower (Carthamus tinctorius L.) is an oil-producing plant, which is considered to be a valuable source of seed oil due to its high oil quality and relatively high resistance to salinity and water-deficit conditions (Mozaffari and Asadi, 2006). In the regions where annual precipitation is low and also the distribution of rainfall is unpredictable, drought is the most important environmental stress that adversely affects crop plant performance. Identifying tolerant cultivars with high yield potential is of paramount significance for researchers under the condition with ever-decreasing rainfall, elevated air temperature and increased hot weather. Delayed sowing in the spring cropping of safflower causes accelerated development, reduced vegetative growth and decreased yield and yield components of the plant (Zimmerman, 1972). The objective of this work was to determine suitable cultivars for the spring and summer cropping seasons under water-shortage conditions.
    Materials And Methods
    This experiment was carried out as split-split plot in a randomized complete block design with four replications at agricultural research station of Kabutarabad in the 2016 growing season. The main factor consisted of two spring and summer sowing dates, the sub-factor comprised of three irrigation treatments (Full Irrigating from sowing to plant maturity as control, irrigation till the beginning of flowering and irrigation till the seed filling period) and the sub-sub factor included nine safflower cultivars: Sofeh, Goldasht, Sina, Faraman, and Mexican cultivars of Mec117, Mec295, Mec18, Mec11 and Mec7. Following seed sowing, and the initial irrigation for plant emergence and establishment, the plots were irrigated after 70 mm cumulative evaporation from evaporation pan class A and cessation of irrigation for plots occurred based on plant growth stage and the irrigation termination treatments.
    Results And Discussion
    The results indicated that there was a significance difference between spring and summer planting dates for all the measured traits. Plant height, plant dry matter at flowering stage, boll numbers, number of seeds in boll, seed weight and seed yield decreased in summer cropping as compared with spring cropping. There was no significant difference in plant dry matter at flowering stage, boll numbers and seed weight under irrigation treatments but other traits showed significant differences. The highest grain yield was obtained when the cultivars received full irrigation (control treatment). Termination of irrigation in the grain-filling period and at flowering reduced grain yield by 25 and 45% as compared to the control. Average seed yield of cultivars in the spring planting was 62% higher than summer planting. The highest seed yield in spring planting was obtained from Sofeh and Goldasht and Mec117 cultivars. But, the greatest seed yield in summer planting was obtained from Sofeh, Goldasht, Sina and Faraman cultivars (The cultivars are mentioned in descending order of yield). Mexican cultivars performed best in spring planting, however, they experienced a significant decline in their seed yield in summer planting. Crop seed yield is reduced when sensitive growth stages e.g. flowering and pollination coincides with adverse environmental conditions such as high temperature (Emami et al., 2011). The observed yield reduction in the safflower cultivars in the second planting date (summer season) is attributable to decreased duration of rosette and vegetative stages. This was due to rapid transition from vegetative to reproductive stage caused by environmental stressors, in particular, high temperature, which prevented the plant from achieving adequate yield- forming components.
    Conclusion
    In general, Iranian cultivars were more resistant to stress and had higher grain yield than Mexican cultivars. Iranian cultivars Sofeh, Sina and Goldasht are suitable cultivars for planting under normal and drought stress conditions for spring and summer cropping seasons.
    Keywords: Planting date, Water stress, Oil crop, seed yield, Boll number
  • Ali Jalilian *, Fardin Hamedi, Adel Nemati, Mehiar Sheikholaslami, Payman Sabeti, Farshad Zandian Pages 50-60
    Introduction
    One of the solutions to increase soil organic matter levels in Iran is to use biological fertilizers such as vermicompost. The use of vermicompost in sustainable agriculture, in addition to increasing the activity of useful microorganisms including mycorrhizal fungi and phosphate soluble microorganisms, serves to provide plants with nutrients e.g. nitrogen, phosphorus, potassium, and eventually to improve crop yield (Arancon et al., 2004). Vermicompost offers numerous advantages, which include: being light and odorless, as well as being free of weed, containing beneficial microorganisms, being a rich source of nutritional elements, possessing plant-growth promoting hormones and having high water and nutrient holding capacity (Farmohammadi and Zandian, 2017).Since the combined use of vermicompost and chemical fertilizer in sugarbeet production has received less attention of researchers, this study was conducted to evaluate the possibility of partial replacement of chemical fertilizer with vermicompost in sugarbeet cultivation and its impact on yield and quality of the crop.
    Materials And Methods
    A field experiment was conducted based on randomized complete block design with four replications at Kermanshah Agricultural Research Center, Kermanshah, Iran during 2013-2014 growing season. An Iranian monogerm sugarbeet cultivar named Ekbatan was used in the study.Eleven experimental treatments included:1-application of 50% recommended dose of chemical fertilizers based on soil test. 2- application of 50% chemical fertilizers plus 3 tons of vermicompost 3- application of 50% chemical fertilizers plus 5 tons of vermicompost. 4-application of 50% of chemical fertilizers plus 7 tons of vermicompost. 5- application of 100% chemical fertilizers. 6- application of 3 tons of vermicompost. 7-application of 5 tons of vermicompost. 8- application of 7 tons of vermicompost. 9-application of 3 tons of vermicompost plus application of 100% chemical fertilizers minus equivalent amount of nutrients in 3 ton vermicompost. 10-application of 5tons of vermicompost plusapplication of 100% chemical fertilizers minus equivalent amount of nutrients in 5 ton vermicompost. 11-application of 7 tonsof vermicompost plus application of 100% chemical fertilizers minus equivalent amount of nutrients in 7 ton vermicompost.
    Results And Discussion
    The results indicated that the effect of the chemical and bio-fertilizers on sugarbeet root yield and gross and net sugar yields was significant.The highest yield of sugarbeet root (57 to 59 t/ha) was obtained from the combined use of chemical fertilizer and vermicompost, and the lowest sugarbeet root yield (42 t/ha) was in the treatment of vermicompost without the application of chemical fertilizer. Since gross and white sugar yields depend on root yield of sugarbeet, the lowest values for these two traits were associated with the treatments No. 6,7 and 8 in which verimcompost was used at the rates of 3 to 7 t/ha without any chemical fertilizers. Reports indicate that vermicompost application at rates between 2 to 7 t/ha had no significant influence on mineral nutrient content of sugarbeet root and sugar percentage, but only resulted in increased sugarbeet root yield (Kabil et al., 2015). Since sugarbeet requires a great amount of nutrients from the soil, in the treatments where no chemical fertilizer was applied (treatments No. 6,7 and 8), the least sugarbeet yields (40.6, 44 and 45 t/ha) were respectively recorded and despite the consumption of vermicompost up to 7 t/ha, it failed to provide the required nutrients for the plant. However, when the sugarbeet plant was treated with 3 to 7 t/ha of vermicompost and was also supplied with 50 % of chemical fertilizer (treatments No. 2, 3 and 4), its yield per hectare was close to the treatment No. 5 (without vermicompost but with full application of chemical fertilizer), which produced 58.3 t/ha sugarbeet yield. This shows that vermicompost and chemical fertilizer are complementary to each other.
    Conclusion
    Our study showed that to achieve long-term environmental benefits, application of 3 to 5 t/ha vermicompost plus 50% of chemical fertilizer is recommended for the sugarbeet cropping. Nevertheless, given the current price of vermicompost, and based on the economic calculations that only take farm profitability into account, it is not economically feasible to use vermicompost in the sugarbeet production. Therefore, there is a need to reduce the production cost for vermicompost.
    Keywords: Vermicompost, Chimical Fertilizer, Sugar beet, Yield
  • Seyed Ali Peighambari *, Hamid Reza Babaei, Hadi Alipour Pages 70-80
    Introduction
    The soybean (Glycine max L.) is one of the most important source of grain oil and protein in the world. It contains 18 to 22% oil and 40 to 50% good quality protein. The low productivity of the pulses especially soybean may be attributed to their susceptibility to pathogenic microorganisms, biotic and abiotic stresses. Soybean production is expected to increase significantly in the world. However, the yield of soybean is still low. The cultivation of soybean in arid and semi-arid areas which face drought and are poor in soil nutrients is one of the main reasons for the low yield of soybean. Evaluation of genetic diversity and identifying genotypes with high yielding potential and tolerant to the environment stresses could be valuable for progressing in future breeding programs.
    Materials And Methods
    In order to evaluate of genetic diversity and tolerance to water deficit stress, 40 soybean genotypes were selected from maturity group III and IV and evaluated in a randomized completely block design (RCBD) under both normal and water deficit conditions, in 2015 on the research field of Seed and Plant Improvement Institute-Karaj, with three replications. Agronomic characteristics were including days to flowering (R1), days to poding (R3), days to beginning of seed forming (R5), days to end of seed filling (R6), seed filling duration (R5-R6), days to beginning of maturity (R7), reproductive stage duration (R1-R7), days to maturity (R8), hundred-seed weight, number of seeds per plant, number of pods per plan, number of pods in sub branches, number of sub branches, plant height, relative water content, oil content, protein and grain yield. After normality test of errors distributions, test of equality of variances and test of the additive effects of treatment and block, data were statistically analyzed using GLM procedure with SAS 9.4. Principal component analysis and drawing of biplots were performed using SPSS 21 and Statgraphics 16, respectively.
    Results And Discussion
    Under both normal irrigation and water deficit condition grain yield, number of seeds per plant and number of sub-branches showed not only higher phenotypic and genotypic coefficient of variation, but also illustrated higher heritability and genetic advance. Grain yield (43.24%), plant height (29.84%), number of seeds per plant (23.53% ), seed filling duration (22.06%) and number of pods per plant (21.69%) showed higher reduction in water deficit stress, respectively, while oil content increased under water deficit stress conditions (11.96%). Days to flowering, number of sub branches, days to poding and days to beginning of seed forming had the least reduction with 0.66, 1.28, 2.83 and 3.81 percent, respectively. The GN-2171, GN-2156, Spry×Savoy/2 and GN-2152 genotypes showed higher grain yield reduction with 88, 74, 66 and 61 percent, respectively while GN-2125, GN-2165 and GN-2002 had lower grain yield reduction with about 10 to 11 percent. Although GN-2125, GN-2165 and GN-2002 genotypes showed lower yield reduction under water deficit stress condition, they did not have higher grain yield under both normal irrigation and water deficit stress conditions. Not only the D42.I4, Spry×Savoy/3, D42.I9 and DI-74 genotypes under both normal irrigated and water deficit conditions had higher grain yield but also they showed lower grain yield under water deficit stress. Corresponding biplot graph, the L6-P79, Chaleston×Mostang/12, D42×Will82, Spry×Savoy/3 and DI-74 genotypes revealed higher values of the factors of grain yield and its components which they could be consider the genotypes with high grain yield in both normal irrigation and water deficit condition.
    Conclusions
    Although, the D42×Will82 and Chaleston×Mostang/12 genotypes had high grain yield in both condition but they showed high reduction in water deficit stress condition. So, they are suitable to be cultivated in both normal irrigation and water deficit stress even though they are relatively sensitive to water deficit stress condition.
    Keywords: grain yield, its components, phenological traits, soybean, water deficit stress
  • Hamid Jabbari *, Nayer Azam Khosh Kholgh Sima, Amir Hosein Shirani Rad Pages 90-100
    Introduction
    Plants are exposed to various environmental stresses, such as drought, salinity and high or low temperatures. Amongst, drought is the most serious problem for global agriculture, approximately affecting 40% of the world’s land area (Zhang et al., 2014). Furthermore, climate change is likely to lead to changes in global temperature and precipitations patterns in some parts of the world, which will have a dramatic impact on crop growth and productivity (Trenberth et al., 2014). Thus, there is an urgent need to develop varieties that can maintain optimum yield levels under drought conditions. Water is one of the major limiting factors affecting plant growth, development and yield, especially in arid and semi-arid regions, where plants are often exposed to periods of water shortage (drought stress).Iran is a vast country with different of climate conditions. It is estimated that approximately 85% of Iran is located in arid, semi-arid or hyper arid regions. It has been reported that annual rainfall, number of rainy-days and monthly rainfall have been significantly decreased in the last few decades, in arid and semi-arid regions of the world and Iran (Modarres & da Silva, 2007). Among the oilseed crops, Brassica species are more affected by drought, as these crops are mainly grown in arid and semiarid areas. Oilseed rape growth and seed production decrease by drought stress. Under drought stress, the percentage of saturated fatty acids decreased, that could be explained by a shorter growing period, and oil yield also decreased. Fatty acid metabolism may be involved in plant adaptation to drought stress. The objective of the present study was to evaluateoil fatty acids composition of Rapeseed cultivars under drought stress conditions in different growth stages
    Materials And Methods
    The experiment was conducted as a split-plot based on a randomized complete block design with three replications at Yazd, Iran in 2011-2012 growing season. Irrigation treatments including control (irrigation after 80 mm evaporation from evaporation pan class A) and drought stress (irrigation withholding starting from stem elongation, flowering and silique formation stages until physiological maturity stages) were allocated to the main plots and three winter type rapeseed cultivars (GKH2005, Opera and Okapi) were considered as the subplots. The measured traits included Oil percentage, Oleic acid, Linoleic acid, Linolenic acid Palmitic acid, Palmitic acid, Gadoleic acid, Stearic acid, Arachidonic acid, Palmitoleic acid, Erucic acid, seed yield and oil yield.SAS statistical software used for data analysis and means were compared with LSD test at 5% probability level.
    Results And Discussion
    The results showed that oleic acid content of rapeseed oil varied from 64 to 68 percent and linoleic acid varied from 15 to 18 percent. Among the three saturated fatty acids (palmitic, stearic and Arachidonic), the irrigation effect was only on Arachidonic acid and among the six unsaturated fatty acids (Palmitoleic, oleic, linoleic, linolenic, Gadoleic and Erucic) the effect of irrigation only on oleic fatty acids, Linoleic and linolenic were meaningful. Irrigation withholding from developmental stages significantly increased oleic acid compared to control treatment, while the amount of linoleic acid decreased significantly. The response of three rapeseed cultivars to irrigation levels for Linoleic fatty acid was different and GKH2005 had the higher linoleic acid, under all of drought stress treatments. Among three cultivars, the highest seed yield was observed in GKH2005 (2211 kg.ha-1).
    Conclusions
    In general, it seems the withholding irrigation resulted in enhanced oleic acid compared to linoleic, in fatty acids composition of rapeseed oil. Moreover, among rapeseed varieties, there was a significant difference in oil fatty acids content. Our findings indicated that GKH2005 had higher seed yield and good quality of fatty acid oils in drought stress than other cultivars.
    Keywords: Oleic acid, Linoleic acid, Linolenic acid, Seed yield