فهرست مطالب

نشریه پژوهش های کاربردی زراعی
پیاپی 127 (تابستان 1399)

  • تاریخ انتشار: 1399/07/22
  • تعداد عناوین: 7
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  • هرمز اسدی*، غلامرضا زمانیان، محمدنبی شهیکی تاش، محمد قربانی، محمدرضا جلال کمالی صفحات 1-23

    اهداف این پژوهش، تعیین آثار نهایی مستقیم و غیرمستقیم عوامل اقلیمی و فنوتیپی، سال معرفی رقم به عنوان تلاش به نژادگران و عوامل مکانی و روند زمانی بر میانگین و واریانس عملکرد دانه لاین های گندم آبی کشور یود. در این مطالعه، داده های پنل از 24 ایستگاه تحقیقات کشاورزی طی دوره 1393-1374 جمع آوری شد. روش تحقیق استفاده از رویکرد تعادل جزیی بوده بطوریکه برای تعیین آثار نهایی از تابع تولید تصادفی جاست- پاپ و تحلیل فضایی دوربین استفاده گردید. طبق نتایج، متغیرهای مورد مطالعه در این پژوهش به روش ایم، پسران و شین مانا بودند. اثر نهایی مستقیم کلیه متغیرهای فنوتیپی(تعداد روزهای تا ظهور سنبله، تعداد روزهای تا رسیدن فیزیولوژیکی، طول دوره پر شدن دانه و وزرن هزار دانه) و متغیرهای اقلیمی (میانگین درجه حرارت سالانه و مجموع بارندگی در فصول زراعی) بر میانگین و واریانس عملکرد دانه لاین های گندم نان آبی از لحاظ آماری معنی داری بود. اثر نهایی مستقیم متغیرهای روند زمانی و سال معرفی رقم، بر میانگین و واریانس عملکرد دانه لاین های گندم آبی در طول دوره مثبت ولی از لحاظ آماری معنی دار نبود. تلاش به نژاد گران توانست در طول دوره، سالانه میانگین عملکرد دانه لاین های گندم نان آبی را 69/5 کیلوگرم در هکتار بهبود بخشد. ضریب تبیین تعدیل شده مدل78/4 درصد محاسبه شد.

    کلیدواژگان: تحقیقات گندم، آثار مستقیم و غیر مستقیم، تابع تولید تصادفی، تحلیل فضایی
  • لیلی صادقی، مسعود رفیعی*، جهانفر دانشیان صفحات 24-45

    خشک سالی های اخیر علاوه بر ایجاد تنش خشکی موجب بروز پدیده ریزگرد بویژه در غرب کشور شده است. تاثیر تنش خشکی و ریزگرد بر خصوصیات فیزیولوژیک گیاه سورگوم دانه ای (Sorghum bicolar L.) در آزمایشی بر پایه طرح بلوک های کامل تصادفی به صورت کرت های خرد شده با 4 تکرار در تابستان سال های 1395 و 1396 در مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی لرستان مورد بررسی قرار گرفت. تنش خشکی از طریق آبیاری پس از 60 (آبیاری مطلوب)، 90 و 120 میلی متر تبخیر از تشتک تبخیر کلاس الف به عنوان عامل اصلی و پاشش ریزگرد در سه سطح عدم کاربرد (شاهد) و کاربرد 50 و 100 میلی گرم در متر مکعب هوا به صورت شبیه سازی در کرت های فرعی قرار گرفت. نتایج نشان داد که تنش خشکی شدید موجب کاهش معنی دار میزان کلروفیل-های a وb و محتوی نسبی آب برگ پرچم (از 81 به 71 درصد) و عملکرد دانه (از 8741 به 6743 کیلوگرم در هکتار) نسبت به تیمار شاهد شد، ولی قندهای محلول (از 3/4 به 9/7 میلی گرم بر گرم ماده تر)، محتوی پرولین (از 25/0 به 66/0 میلی گرم بر گرم ماده تر) و درجه حرارت برگ افزایش معنی داری داشت. اگرچه اثر ریزگرد بر هیچ یک از صفات معنی دار نشد، لیکن با افزایش غلظت ریزگرد بطور خطی از محتوی نسبی آب برگ پرچم کاسته و بر درجه حرارت برگ افزوده شد.

    کلیدواژگان: عملکرد، اجزای عملکرد، صفات بیوشیمیایی، محتوی نسبی آب
  • فاطمه عبدی، یوسف نیک نژاد*، هرمز فلاح، سلمان دستان، داود براری تاری صفحات 46-68

    کودهای زیستی به عنوان نهاده های بوم سازگار می توانند باعث کاهش مصرف کودهای شیمیایی و بهبود حاصلخیزی خاک شوند. مصرف کودهای زیستی و سیلیسیم به ویژه محلول پاشی نانوسیلیس می تواند در دستیابی به عملکرد مطلوب و پایدار و همچنین کاهش آلودگی محیط زیستی موثر باشد. از این رو، این پژوهش با هدف بررسی برهمکنش منابع کودی سیلیسیم و فسفر بر شاخص های مرتبط به خوابیدگی بوته و مولفه های کمی و کیفی برنج در منطقه آمل طی سال های 1396 و 1397 انجام شد. آزمایش به صورت کرت های خرد شده در قالب طرح پایه بلوک های کامل تصادفی با سه تکرار اجرا شد. منابع مختلف کود سیلیس شامل شاهد (عدم مصرف)، سیلیکات کلسیم و سیلیکات پتاسیم به صورت خاک مصرف و محلول پاشی نانوسیلیکون به عنوان عامل اصلی و منابع مختلف کود فسفر شامل شاهد (عدم مصرف)، سوپرفسفات تریپل (100 کیلوگرم در هکتار)، باکتری هرباسپیریلوم + 50 کیلوگرم سوپرفسفات تریپل در هکتار و قارچ مایکوریز + 50 کیلوگرم سوپرفسفات تریپل در هکتار به عنوان عامل فرعی در نظر گرفته شدند. نتایج نشان داد هیچ کدام از صفات مورد مطالعه در آزمون بارتلت معنی دار نشدند که برای این صفات تجزیه واریانس مرکب انجام شد. کمترین شاخص خوابیدگی با محلول پاشی نانوسیلیس حاصل شد. بالاترین میزان عملکرد شلتوک (5147 کیلوگرم در هکتار) در اثرمتقابل محلول پاشی نانوسیلیس و مصرف ترکیبی فسفر + تلقیح باکتری به دست آمد که از این نظر نیز مصرف خالص فسفر و مصرف کود + تلقیح قارچ به ترتیب در رتبه های بعدی قرار گرفتند. بنابراین، محلول پاشی نانوسیلیس و مصرف ترکیبی کود + تلقیح بذر با باکتری می تواند موجب افزایش عملکرد کمی و کیفی و کنترل بلاست برنج شود.

    کلیدواژگان: باکتری هرباسپیریلوم، برنج، کارایی استفاده از عناصر، قارچ مایکوریز، نانو سیلیس
  • مریم آریان مهر، علی قنبری*، رضا قربانی، مهدی نصیری محلاتی، رضا خراسانی، قربانعلی اسدی صفحات 69-93

    مدیریت علف های هرز و کود نیتروژن در تولید ذرت علوفه ای، دو مسئله حایز اهمیت می باشند. در این مطالعه اثر روش های مختلف کنترل علف های هرز و منابع کود نیتروژن بر کنترل علف های هرز و خصوصیات کمی و کیفی ذرت علوفه ای ارزیابی شد. آزمایش به صورت اسپلیت پلات و در قالب طرح بلوک کامل تصادفی در دو سال زراعی 95-1394 در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد انجام شد. روش مدیریت علف های هرز در سه سطح (کنترل تلفیقی (شیمیایی +مکانیکی)، کنترل شیمیایی و شاهد علف های هرز) به عنوان عامل کرت اصلی و منبع کود نیتروژن در پنج سطح (اوره، آمونیوم سولفات، کلسیم نیترات، آمونیوم نیترات فسفات و شاهد بدون کود) به عنوان عامل کرت فرعی در نظر گرفته شدند.کارایی کنترل تلفیقی نسبت به کنترل شیمیایی در کاهش وزن خشک علف های هرز، در سال اول و دوم به ترتیب حدود 68 و 57 درصد بیشتر بود که این کارایی بیشتر منجر به افزایش عملکرد نهایی علوفه خشک ذرت حدود 17 و 14 درصد شد.ضمن اینکه مصرف علف کش در کنترل تلفیقی نسبت به کنترل شیمیایی، 25 درصد کاهش یافت. بااین وجود کنترل شیمیایی علف های هرز نیز موجب کاهش 71 و 79 درصدی وزن خشک علف های هرز نسبت به شاهد علف های هرز به ترتیب در سال اول و دوم شد. ب ه طورکلی بیشترین عملکرد کمی و کیفی علوفه ذرت شامل (عملکرد ماده خشک، عملکرد پروتئین خام و عملکرد ماده خشک قابل هضم) با اعمال کنترل تلفیقی علف های هرز به همراه مصرف کودهای آمونیوم نیترات فسفات و آمونیوم سولفات حاصل شد.

    کلیدواژگان: کنترل تلفیقی، آمونیوم، نیترات، کیفیت علوفه
  • سمیه تکاسی*، ابراهیم کازرونی منفرد، پرویز رضوانی مقدم، مهدی نصیری محلاتی صفحات 93-113

    برای برآورد درصد و زمان آبی گرمایی سبزشدن جودره (H. spontaneum) و کاهوی وحشی (L. serriola)، در دما و رطوبت-های مختلف با کاربرد مدل زمان آبی گرمایی، دماهای 15، 25 و 35 درجه سانتی گراد (°C) و پتانسیل های آبی 045/0- و 172/0- مگاپاسکال (MPa) در آزمایشگاه و تاریخ کشت های مهر و آبان (برای جودره) و اسفند، فروردین و اردیبهشت (برای کاهوی وحشی) و سه دور آبیاری (3، 5 و 7 روز یک بار) در مزرعه مورد مطالعه قرار گرفت. نتایج آزمایشگاهی نشان داد بیشترین و کمترین سبزشدن جودره به ترتیب 6/92 و 3/66 درصد در °C15، MPa 045/0- و °C25، MPa 172/0- و کاهوی وحشی به ترتیب 5/95 و 20 درصد در °C15، MPa 045/0- و °C35، MPa 172/0- بود. بیشترین و کمترین زمان گرمایی %50 سبزشدن جودره به ترتیب 6/209 و 8/99 سانتی گراد-روز در °C25، MPa 045/0- و °C15، MPa 172/0- و کاهوی وحشی به ترتیب 70 و 7/49 سانتی گراد-روز در °C15، MPa 172/0- و °C35، MPa 172/0- برآورد شد. نتایج مزرعه ای نشان داد بیشترین سبزشدن جودره و کاهوی وحشی به ترتیب6/97 و 2/56 درصد در آبان، سه روز یک بار آبیاری و فروردین، پنج روز یک بار آبیاری و کمترین به ترتیب 8/72 و 3/21 درصد در مهر، سه روز یک بار آبیاری و اردیبهشت، هفت روز یک بار آبیاری برآورد شد. بیشترین زمان آبی گرمایی %50 سبزشدن جودره و کاهوی وحشی به ترتیب2/384 و 2/179 مگاپاسکال-سانتی گراد روز در مهر، هفت روز یک بار آبیاری و اردیبهشت، پنج روز یک بار آبیاری و کمترین به ترتیب6/84 و 3/43 مگاپاسکال-سانتی گراد روز در آبان، سه روز یک بار آبیاری و اسفند، سه روز یک بار آبیاری برآورد شد.

    کلیدواژگان: پتانسیل آب، دمای خاک، علف هرز، سبز شدن بذر، مدل زمان آبی-گرمایی
  • فرشاد بختیار*، گودرز نجفیان، نوید شارسودا صفحات 114-134

    در این تحقیق تعداد 291 لاین گندم نان با هدف انتخاب لاین های متحمل تنش خشکی آخر فصل به روش مشاهده ای بدون تکرار در دو شرایط نرمال و تنش مورد مطالعه قرار گرفتند. از صفات درصد سبز، تعداد روز تا سنبله دهی، رسیدگی فیزیولوژیک، ارتفاع بوته، رنگ دانه، وزن هزار دانه، درصد خوابیدگی، ریزش دانه، و عملکرد دانه یادداشت برداری شد. شاخص های STI ، TOL ، GMP ، MP و SSI برای صفات وزن هزاردانه و عملکرد دانه در کلیه ژنوتیپ ها محاسبه شدند و در نهایت تعداد 34 لاین برتر و متحمل تنش خشکی آخر فصل با توجه به شاخص های STI و SSI در دو مرحله مورد گزینش قرار گرفتند. تجزیه و تحلیل شجره نامه لاین های انتخابی نشان داد که ژنوتیپ های PASTOR ،WBLL1 ،SKAUZ و Y50E به ترتیب با 21/11 ، 34/6، 04/4 و 04/4 درصد بیشترین سهم و ژنوتیپ های CHIBIA ،KACHU و 1-73-240 به ترتیب با 01/0، 02/0 و 02/0 درصد کمترین سهم را در ریخته ارثی لاین های متحمل تنش خشکی آخر فصل داشتند. همچنین سهم برخی از ارقام گندم مانند امید، پیشتاز، پارسی، مرودشت، البرز و اترک در ریخته ژنتیکی لاین های انتخاب شده به ترتیب 78/2، 39/2، 47/1، 47/1، 44/1و 09/0 درصد بود. با توجه به نتایج پیشنهاد می شود که علاوه بر ارقام گندم فوق می توان از ارقامی که دارای ریخته ارثی ژنوتیپ های PASTOR ، KAUZ ، SKAUZ ، WBLL1 ، PBW343 ، Y50E و MUNAL #1 باشند نیز در برنامه تولید ژرم پلاسم با صفات زراعی مناسب و متحمل تنش خشکی آخر فصل در اقلیم معتدل کشور استفاده کرد.

    کلیدواژگان: عملکرد دانه، تنش، خشکی آخر فصل
  • زهرا امیری قنات سامان، بهاره پارسامطلق*، مهدیه امیری نژاد، امان الله سلیمانی صفحات 135-151

    به منظور بررسی و تعیین بهترین تاریخ کاشت و رقم کلزا، آزمایشی به صورت کرت های خردشده در قالب طرح بلوک های کامل تصادفی با سه تکرار در مزرعه ی پژوهشی دانشگاه جیرفت در سال زراعی 97-1396 اجرا شد. شش تاریخ کاشت 10 و 24 آبان ، 8 و 22 آذر، 6 و 20 دی به عنوان عامل اصلی و چهار رقم کلزا هایولا 50، آگامکس، تراپر و دلگان به عنوان عامل فرعی در نظر گرفته شدند. صفات تعداد غلاف در بوته، وزن غلاف در بوته، تعداد دانه در غلاف، طول غلاف، وزن هزار دانه، عملکرد زیست توده، عملکرد دانه، شاخص برداشت، عملکرد پروتئین و عملکرد روغن دانه مورد ارزیابی قرار گرفتند. نتایج نشان داد تاریخ کاشت بر تمامی صفات مورد مطالعه اثر معنی داری داشت. نتایج تاثیر رقم حاکی از آن بود که ارقام مورد بررسی به جز شاخص برداشت از لحاظ سایر صفات مورد بررسی با یکدیگر اختلاف معنی داری داشتند. اثر متقابل تاریخ کاشت در رقم به استثنای صفت طول غلاف و شاخص برداشت بر سایر صفت موردبررسی معنی دار بود. بیشترین تعداد غلاف در بوته (44/52 عدد)، تعداد دانه در غلاف (96/30 عدد)، عملکرد دانه (3/1613 کیلوگرم در هکتار)، عملکرد پروتئین (34/234 کیلوگرم در هکتار) و عملکرد روغن (68/826 کیلوگرم در هکتار) از تاریخ کاشت 8 آذر و رقم آگامکس حاصل شدکه در مقایسه با ارقام تراپر، هایولا 50 و دلگان بترتیب 28/12، 45/19 و 44/28 درصد افزایش عملکرد دانه داشت. با توجه به نتایج حاصل در شرایط اقلیمی منطقه جیرفت رقم آگامکس در تاریخ کاشت نیمه اول آذر ماه پیشنهاد می شود.

    کلیدواژگان: شاخص برداشت، عملکرد پروتئین، عملکرد روغن، عملکرد زیست توده
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  • Hormoz Asadi *, Gholamreza Zamanian, Mohammad.Nabi Shahiki Tash, Mohammad Ghorbani, Mohammadreza Jalal Kamali Pages 1-23
    Introduction 

    One of the important and effective economic activities in the field of agricultural economics is to release varieties or to adopt crop improvement technology. This can result in increased yield and production of various crops, enhanced food security, self-reliance and reduced dependency (Aghaei & Asadi, 2010 ). Historically, breeders have focused more on increasing yield of varieties. However, reducing variability and instability in yield of varieties at different locations and times is considered as an important breeding goal (Byerlee & Moya, 1993).The objectives of this research were to determine the direct and indirect marginal effects of climatic and phenotypic factors, variety release year as breeders’ efforts in genetic improvement, location and time trend factors on the mean and variance of grain yield of irrigated wheat lines. Materials and .

    Methods

    In this study, the required panel data were collected from 23 agricultural locations method and the marginal effects of the variables on the mean and variance of wheat grain yield were assessed using stochastic production function of Just and Pope and spatial durbin models (SDMs). Just and Pope production function was estimated with linear functions in three steps as follows.(Just & Pope, 1979). Where; Yht: mean yield of bread wheat lines (kg/ha) in year t, trend: time trend, Ln (ei ) 2 : yield risk for wheat lines in year t,, DHE: days to heading in year t, DMA: days to physiological maturity, GFD: mean of grain filling duration in year t, TGW: thousand grain weight (TGW) (g), MTem: mean of annual temperature ( MTem ) (0 C), S9Rain: sum of rainfall during cropping season ( S9Rain ) (mm), pH , DLoch : Dummy variables of locations, RLyear(h=1, 2,..23): variety release year, Φ.β: δ, ɑ: models parameters and ϵht:, residuals

    Results and Discussion

    According to the results, the study of spatial spillover effects using spatial durbin models (SDM) showed that the direct marginal effects of all the phenotypic and climatic factors on the mean and variance of grain yield of irrigated bread wheat lines were statistically significant. The direct marginal effect of time trend and variety release year on the mean and variance of grain yield of irrigated bread wheat lines was positive but not statistically significant .

    Conclusion 

    In general, the direct marginal effects of all the phenotypic factors on the mean of grain yield of irrigated wheat lines was satistically significant. The direct marginal effect of time trend and variety release year on on the mean of grain yield of irrigated wheat lines was positive.

    Keywords: Wheat Research, Direct, Indirect Effects, Stochastic Production Function, Spatial Analysis
  • Leili Sadeghi, Masoud Rafiee *, Jahanfar Daneshian Pages 24-45

    Introduction

    Abiotic stresses, in particular, water shortage pose immense challenges to crop production and can decrease crop yields by 50% worldwide (Mahajan Tuteja, 2005). Water deficit has negative impacts on growth, development and production of legumes, which may result in decreased chlorophyll a and b and increased proline content of leaf (Karimi et al., 2016). Aerosols are principal air pollutants that can greatly impact human health and plant development. This natural phenomenon, which mainly occurs in Iraq and Iran`s western regions, has exacerbated in recent years and caused a lot of damage (Marsafari, 2011). The objective of this study was to evaluate the effects of aerosol particles and drought stress on grain sorghum photosynthetic pigments, soluble sugars, proline, relative water content of flag leaf, leaf temperature and grain yield.

    Materials and Methods

    The research was conducted to investigate the effect of drought and aerosol stresses on morpho-physiological traits of grain sorghum (Sorghum bicolar L.) at Lorestan Agricultural and Natural Resources Research and Education Center in 2015. A split plot design based on RCBD was used with four replications. The main plots were allocated to four different irrigation regimes: watering after 60, 90 and 120 mm evaporation from pan class A. The subplots were assigned to three levels of aerosols derived from clay soil source) control treatment, 50 and 100 mg m-3 aerosol particles (. Chlorophyll a, chlorophyll b, soluble sugars, proline content, relative water content and leaf temperature were measured at flowering period and yield components and grain yield were measured at harvest time.

    Results and Discussion 

    The results of the first year of the experiment showed that chlorophylls a and b were only affected by drought stress where they were linearly significantly decreased from 0.017 and 0.012 mg/g FW, respectively, in control treatment, to 0.0068 and 0.0065 mg/g FW in I120 treatment with increasing drought stress. Water stress triggered the production of active oxygen along with the reduction and decomposition of chlorophyll (Karimi et al., 2016). Soluble sugars and proline leaf concentration were not affected by aerosols, but were significantly affected by drought stress. Sugar content linearly and significantly increased from 4.3 mg/g under normal moisture conditions to 7.9 mg/g fresh leaf weight in I120 treatment. Proline concentrations were linearly and significantly increased from 0.25 mg/g under normal moisture conditions to 0.66 mg / g leaf fresh weight in I120 treatment. The results of two-year compound variance analysis indicated that grain number per panicle decreased but thousand grain weight increased due to drought stress. The change in grain yield was attributed to significant linear relationship and negative correlations with increasing drought stress. The highest average grain yield (8257 kg/ha) was obtained from the normal irrigation, which decreased to 6393 kg/ha under drought stress. The highest average relative content of flag leaf water was obtained from the normal irrigation, which was 2.80% and was reduced to 70.3% under drought stress.

    Conclusion 

    In general, it was found that the amount of chlorophylls a and b and the relative water content of flag leaf and, as a result, grain yield were significantly decreased with increasing drought stress, but osmotic compounds (sugars solution and proline content of leaf) and leaf temperature increased significantly. Increasing drought stress decreased the number of grains per panicle and increased 1000-grain weight, but the increase in 1000-grain weight could not compensate for the decrease in the number of grains per panicle and consequently led to the decreased grain yield. Low concentration of aerosols on the sorghum leaves due to being vertical and waxy caused no serious damage to the plant's photosynthetic system and as a consequence to grain production.

    Keywords: biochemical traits, relative water content, yield, Yield components
  • Fatemeh Abdi, Yosoof Niknezhad *, Hormoz Fallah, Salman Dastan, Davood Barari Tari Pages 46-68
    Introduction

    The major problem of paddy fields in Mazandaran province is the low solubility and uptake of phosphorus. This essential macro-element for plants is added to the soil as phosphorus fertilizer; but, the major part of this element is immobilized due to fixation in the soil and is unavailable for the crop plant (Zhu et al., 2011). The consequence is that farmers are turning to intensive farming and high consumption of chemical inputs (Ramezani & Hanifi, 2011). Therefore, to solve this problem, the plant growth promoting rhizobacteria (PGPB) and plant growth promoting fungi (PGPF) in the rhizosphere as well as insecure phosphate solubilizing bacteria (PSB) and phosphate solubilizing fungi (PSF) can be considered as a solution for providing consuming phosphorus for the crops (Lavakush et al., 2014). Other key solutions to solving this problem is the consumption of silicon fertilizer sources, which can be very beneficial. In fact, silicon increases phosphate uptake due to convergence with phosphorus. In addition, silicon consumption reduces plant lodging index and pests and diseases of crops (Datnoff, 2011). Therefore, this research was conducted with the aim of investigating the interaction of silicon and phosphorus fertilizer resources on the lodging indices and quantitative and qualitative parameters of rice.

    Material and Methods

    The experiments was conducted as split plots based on a randomized complete blocks design (RCBD) with three replications in Amol region during 2017 and 2018. Four levels of silicon fertilizer including control (non-consumption), spray of nano-silicon, soil consumption of potassium silicate and soil consumption of calcium silicate were used as main plots and four levels of phosphorous fertilizer including control (non-consumption), chemical fertilizer (100 kg P2O5 ha-1), 50 kg P2O5 ha-1 + Herbaspirillum seropodicae bacteria inoculation and 50 kg P2O5 ha-1 + mycorrhiza fungi (Gholusmosseae) inoculation were used as sub plots. During the growth period, after the removal of marginal effect, traits were randomly measured according to the Standard Evaluation System (SES) of the International Rice Research Institute (IRRI). All statistical analysis was performed using the SAS software. A two-way analysis of variance (ANOVA) was used by GLM procedure and the least significant difference (LSD) test was used to compare the differences among treatment means at a 5% probability level.

    Results and Discussion

    In order to investigate the effect of silicon and phosphorous consumption on rice in the two years, firstly the data were measured by using the Bartlett method of variance homogeneity test. The results demonstrated that all the investigated traits were non-significant in the Bartlett's test, for which combined analysis of variance was performed. The lowest lodging index was obtained by spraying nano-silicon. But, the lodging index with phosphorus treatment was vs silicon usage that the highest lodging index was obtained by using chemical fertilizer + bacteria inoculation. The highest paddy yield (5147 kg ha-1) was obtained at interaction of nano-silicon spraying and using chemical fertilizer + bacteria inoculation, in this regard, chemical fertilizer treatment along with using chemical fertilizer + fungi inoculation got ranks next, respectively. Spray of nano-silicon leads to higher uptake of nutrient (Si, N, P and K) and improving qualitative and quantitative product compared to soil consumption of potassium silicate and calcium silicate, in this regards potassium silicate and calcium silicate stood ranks second and third, respectively. In addition, combined consumption of phosphorus + bacterial inoculation had higher positive effect on nutrients (Si, N, P and K) uptake than chemical phosphorous uptake along with phosphorus + fungi inoculation.

    Conclusion

    According to findings, it can be concluded that spray of nano-silicon along with consumption of chemical fertilizer + seed inoculation with bacteria can increase the quantitative and qualitative yield of rice and control the blast disease in the paddy fields.

    Keywords: Herbaspirillum bacteria, Mycorrhiza fungi, Nano-silicon, Nutrient utilization efficiency, rice
  • Maryam Arianmehr, Ali Ghanbari *, Reza Ghorbani, Mahdi Nasiri Mahalati, Reza Khorasani, Ghorban Ali Asadi Pages 69-93
    Introduction

    Two important factors in producing forage maize (Zea mays L.) are weed control and nitrogen fertilizer management. Low maize yields are typically attributed to low corn growth rate at the beginning of the growing season, wide spacing of plant rows and rapid establishment of weeds. Weeds are a major challenge to row crops and research has usually emphasized on the integrated weed management using chemicals and mechanical control (Chauhan, 2013). In modern agriculture, weed control is primarily done with herbicides due to the effectiveness and ease of use. However, environmental concerns about pollution of groundwater and surface water, have led researchers to focus on integrated weed management and reduced herbicide consumption. On the other, selection of nitrogen fertilizer source may be an important component of weed management. Some studies have investigated nitrogen fertilizer management in order to integrated weed management. The present study was carried out to investigate the effect of chemical control and mechanical + chemical control of weeds and different sources of nitrogen fertilizer on weeds control and quantitative and qualitative characteristics of forage maize.

    Materials and Methods

    This experiment was conducted with a factorial arrangement based on randomized complete block design with three replications at the experimental station of Ferdowsi University of Mashhad during the growing season of 2015 -2016. The treatments were control methods of weeds including chemical control, integrated control (mechanical+chemical) and weedy control, and the sources of nitrogen fertilizers including urea (U), ammonium sulfate (AS), calcium nitrate (CN), ammonium nitrate phosphate (ANP) and no fertilizer (NF). In this study, Kjeldahl method was used to measure nitrogen content of the forage. Crude protein (CP) of forage maize was calculated using the following equation (1). Measurements of acid detergent fiber (ADF) and neutral detergent fiber (NDF) was done based on Van Soest method (1967). The equation (2), proposed by Oddy et al (1983) was used to determine digestible dry matter (DMD). Equation 1: 6.25 × N (%) = CP (%) Equation 2: DMD (%) =83.58 – 0.82 ×ADF(%) + 2.262 × N(%).

    Results and Discussion

    The integrated control of weeds reduced dry matter of weeds compared to chemical control by 68% and 57% in the first and second year of the experiment, respectively (50 days after corn planting), leading to increased dry matter yield of maize by 17% and 14%, respectively. Furthermore, in the integrated control, herbicide consumption decreased 25% compared to chemical control. However chemical control of weeds reduced dry matter of weed compared to weedy control by 71% and 79% in the first and second year, respectively. The greatest dry matter yield (DM-Y), dry matter digestible yield (DMD-Y) and crude protein yield (CP-Y) were observed with the integrated control and ANP or AS application (there were no significant differences between ANP and AS fertilizers), while the lowest DM-Y, DMD-Y and CP-Y were obtained with weedy control (there were no significant differences between fertilizers treatment).

    Conclusion

    In the integrated control with proper implementation to reduce weed dry matter, not only did increased quantitative and qualitative yield of forage but also herbicide consumption decreased 25% compared to chemical control. Reducing herbicide consumption through integrated weed management will preserve the environment, improve human health and increase product quality and quantity. On the other hand, it seems that (ANP and AS) as nitrogen fertilizer sources are more effective in terms of increasing maize production compared to other nitrogen sources. It can be suggested, using ANP fertilizer that contains both nitrogen forms (nitrate and ammonium) leads to increasing maize yield. Also, assimilation of ammonium requires the low energy and occurs faster than nitrate in plants. This energy savings may lead to greater dry weight production for plants with an ammonium diet. In addition, the sulfur in AS fertilizer as an essential element for plants may improved plant growth and metabolism.

    Keywords: Integrated control, Ammonium, Nitrate, Quality of forage
  • Somayeh Tokasi *, Ebrahim Kazerooni Monfared, Parviz Rezvani Moghadam, Mehdi Nasiri Mahalati Pages 93-113
    Introduction

    Seed germination and emergence is a key event that determines the success of a weed in an agro ecosystem that is influenced by many environmental factors such as temperature, pH, light, salinity and moisture (Chauhan & Johnson, 2008). Temperature plays a major role in determining the periodicity of seed germination, emergence and the distributions of weed species (Guan et al., 2009). Also, osmotic stress can reduce, delay or prevent germination (Zhou & Deckard, 2005). An understanding of weed development is needed to design effective weed management programs. A better understanding of the biology of seed germination and emergence could contribute to the development of weed management technologies to help counter those undesirable shifts in weed populations. The hydrothermal time models have been widely applied to describe the germination responses of seeds to temperature and water potential. This study was carried out with the aim to predict the time and maximum seedling emergence of two weed species, wild barley (Hordeum spontaneum Koch.) and prickly lettuce (Lactuca serriola L.).

    Material and Methods

    Different temperatures (15, 25 and 35°C) and water potentials (-0.045 and -0.172 MPa) as full factorial experiments applying a randomized experimental design with four replications were investigated in laboratory and planting dates (October and November) for H. spontaneum seeds and March, April and May for L. serriola and three irrigation intervals: every 3 days once (level1), every 5 days once (level2) and every 7 days once (level3) for two species as full factorial experiments applying a completely randomized experimental design with three replications were investigated in field. To express the changes in the emergence process, hydrothermal time model was applied and the base temperature and water potential were calculated. Then, MPa-°C-days required for emergence was calculated with the base temperature and water potential and soil moisture and temperature.

    Results and discussion

    The results of the laboratory experiments showed that the maximum germination percentage of wild barley at 15 and 25°C was 95.9 and 83.7 %, respectively and for prickly lettuce at 15, 25 and 35°C was 96.3, 79.9 and 60.9 %, respectively. The highest and lowest maximum emergence percentage of wild barley was at 15°C, -0.045 MPa and 25°C, -0.172 MPa, respectively that was 92.6 and 66.3 %, respectively and for prickly lettuce was at 15°C, -0.045 MPa and 35°C, -0.172 MPa, respectively that was 95.5 and 20.0 %, respectively. Thermal time required for germination of wild barley at 15 and 25 °C was 43.8 and 65.1 °C-days, respectively and for prickly lettuce at 15, 25 and 35 °C was 44.6, 31.7 and 32.9 °C-days, respectively. The highest and lowest thermal time required for 50% emergence of wild barley was at 25 °C, -0.045 MPa and at 15°C, -0.172 MPa, respectively that was 209.6 and 99.8 °C-days, respectively and for prickly lettuce was at 15°C, -0.172 MPa and at 35°C, -0.172 MPa, respectively that was 70.0 and 49.7 °C-days, respectively. The results of the field experiment showed that the highest emergence percentage of wild barley and prickly lettuce was 97.6 and 56.2% that occurred in November with irrigation interval of every 3 days once and April with irrigation interval of every 5 days once, respectively. The lowest emergence percentage of wild barley and prickly lettuce was 78.2 and 21.3% that occurred in October with irrigation interval of every 3 days once and May with irrigation interval of every 7 days once, respectively. The highest hydrothermal time for 50% emergence of wild barley and prickly lettuce was 384.2 and 179.2 °C-days-MPa in October with irrigation interval of every 7 days once and May with irrigation interval of every 5 days once and the lowest was 84.6 and 43.3 °C-days-MPa in November with irrigation interval of every 3 days once and march with irrigation interval of every 3 days once, respectively.

    Keywords: Water potential, Soil temperature, weed, Seed emergence, hydrothermal time model
  • Farshad Bakhtiar *, Goodarz Najafian, Navid Sharsoda Pages 114-134
    Introduction

    Drought Stress is one of the most important and common environmental stresses that restricts agricultural production and reduces production efficiency in semi-arid and dryland areas (Sarmadnia, 1993). Information on yield stability of genotypes under both favorable and drought stress conditions is essential to identify drought-tolerant genotypes by plant breeders and genotypes with good performance in both environments are preferred (Uddin et al., 1992). In International Maize and Wheat Improvement Center (CIMMIT), the F3 and F4 generations are selected under limited irrigation conditions. The selected plant materials in the fifth and sixth generations are evaluated under normal conditions, and in seventh and eighth generations performance comparison and other evaluations are studied under water stress and natural conditions. This method of evaluation and selection under stress and non-stress conditions has been suggested and applied by many researchers on wheat and other crops (Ehdaie et al., 1988). The goal of this study was selection of drought tolerant bread wheat lines based on their tolerance indices and pedigree analysis.

    Materials and Methods

    In this experiment, 291 lines and cultivars of bread wheat along with four check cultivars including Parsi, Pishtaz, Sirvan, and Sivand were evaluated to identify tolerant genotypes for terminal drought using two identical experiments, one under non-stress condition and the other one under drought stress condition (irrigation cut-off after 50% of anthesis). Experiments were conducted using the observational method without replication. During the developmental stages, the traits including green percentage, days to heading, days to maturity, plant height, grain color, thousand-grain weight, lodging percentage, shattering and grain yield per plot were recorded. Drought susceptibility and tolerance indices such as STI, SSI, GMP, MP and TOL were calculated for all the investigated entries based on 1000-grain weight and grain yield. In order to investigate the genetic background of selected lines, the percentage of genetic contributions of each genotype was calculated based on the pedigree of the lines.

    Results & Discussion

    The results indicated that under both stress and non-stress conditions, the selected lines were relatively early mature. Comparison of arithmetic means (MP), geometric mean (GMP) and drought tolerance index (STI) of the genotypes revealed that selection based on these criteria leads to the selection of high yield genotypes under both stress and non-stress conditions. In terms of grain yield, genotypes 33, 2, 34, 23, 10 and 11 had the lowest SSI, which was associated with a higher yield of these lines under drought stress. Also, in terms of 1000-grain weight, genotypes 10, 11, 32, 33, 34, 8 and 5 had the lowest SSI indices where this trait was significantly correlated with high seed weight under drought stress. Lines 11, 14 and 34 had the highest STI index for grain yield and 1000-grain weight, which was significantly associated with high grain yield and 1000-grain weight under normal conditions. Finally, 34 superior drought tolerant lines were selected in two stages according to STI and SSI indices. Pedigree analysis of the selected lines showed that genotypes PASTOR, WBLL1, SKAUZ, and Y50E had contributions of 11.21%, 6.34%, 4.04%, and 4.04% in germplasm composition under drought condition, respectively, indicating their impact on drought tolerance. On the other hand, genotypes CHIBA, KACHU and 1-73-240 had 0.01%, 0.02%, and 0.02% contribution in germplasm composition under drought conditions, respectively, showing no influence in drought tolerance.

    Conclusion

    The results of this study showed that the genetic structure of some Iranian wheat cultivars such as Omid, Pishtaz, Parsi, Marvdasht, Alborz and Atrak, respectively, made contributions of 2.78%, 2.39%, 1.47%, 1.47% and 1.44% to the genome of the selected lines. Finally, it was suggested that, in addition to the above-mentioned Iranian cultivars, breeding lines derived from genotypes such as PASTOR, KAUZ, SKAUZ, WBLL1, PBW343, Y50E and MUNAL #1 can be used in breeding programs to produce suitable germplasm with early maturity and tolerance to terminal-drought stress for temperate climate of Iran.

    Keywords: Grain yield, Stress, terminal drought
  • Zahra Amiri Ghanat Saman, Bahareh Parsa Motlagh *, Mahdiyeh Amiri Nejad, Aman Allah Soleimani Pages 135-151
    Introduction

    Rapeseed (Brassica napus L.) is one of the most important oily seeds that can be planted under different climatic conditions of Iran (Koocheki & Khajehossini, 2008). One of the factors affecting the performance of rapeseed is planting date. Determining the response of different varieties of crops to environmental variables from planting to harvest is one of the basic principles of agricultural planning in order to achieve maximum yield and quality. Delay in planting results in prolonged grain filling period and high temperature. These conditions result in a decrease in grain yield (Ehshamami et al., 2016). Saberi and Arazmjo (2015) in the study of the effect of planting date on yield and some of agronomic traits of five rapeseed cultivars in Birjand region observed that the cultivars that flowered at the right time produced more pods per plant and had higher seed weight than other cultivars.

    Materials and Methods

    A field experiment was conducted at the experimental station of Faculty of Agriculture, University of Jiroft (latitude: 28°40´ N; longitude: 57°44´ E; elevation: 650 m) in the growing season of 2016-2017. A split plot layout with a randomized complete block design with three replications was used. The main plots were sowing date at six levels of November 1st, 15th and 29th, December 15th and 27th and January 10th, Rapeseed cultivars were Hyola, Agamax, Traper and Delgan as the sub plot. Each plot was 3×6 m2 and the cultivars were sown in 30 cm intra-rows and 6 cm inter-rows. During the growing season, hand weeding was performed for several times. Drip system was used for irrigation. After harvest, the following traits were measured; number of pods per plant, pod weight per plant, number of seeds per pod, pod length, 1000 seed weight, seed yield, biomass yield, harvest index, protein yield and oil yield. Soxhlet method was used to measure oil content and Kjeldahl method was used to measure protein.

    Results and Discussion

    The results showed that planting date had a significant effect on all traits (p < 0.05). Interaction effect of planting date × cultivar was significant in the studied traits except for pod length and harvest index. The highest number of pods per plant (52.42), number of seeds per pod (30.96), grain yield (1613.3 kg ha-1), protein yield (234.3 kg / ha-1) and oil yield (68 / 826 kg ha-1) was achieved at the planting date of November 29th with Agamax cultivar. The planting dates of November 1st and 29th produced the highest pod weight per plant of 3.1 g and 1.34 g in Agamax cultivar and of 1.28 g in Teraper cultivar, respectively. The highest 1000-seed weight was observed in Delgan cultivar (5.58 g) at the planting date of November 29th which was followed by Agamax cultivar (3.6 g) at the planting date of November 1st. The highest seed and biomass yield at the planting dates of November 1st, 15th and 29th was recorded with Agamax cultivar, which averaged 6500, 6463.3 and 7043.3 kg/ha, respectively. The highest oil and protein yield was related to Agamax cultivar on November 29th and the lowest protein yield was observed with Dalgan on December 13th. The results of this study were similar to Ehshamami et al., 2016.

    Conclusion 

    In general, the results of this study showed that planting date had a significant effect on phenological and morphological attributes, oil and protein yields of the rapeseed cultivars. Changes in rapeseed planting date made the plant developmental stages encounter different ecological factors that consequently affected the production of this crop. Delay in planting resulted in the loss of suitable growing conditions and the failure of the crop to reach its potential. Also, delay in planting caused the grain filling period and the accumulation of oil to coincide with higher temperatures, which led to a decrease in seed, oil, and protein yields. Also, according to the climatic conditions of the region during the 2016-2017 growing season, the most appropriate date for sowing of rapeseed in Jiroft was November 29th. The planting dates of December 27th and January 10th were considered inappropriate as the cultivars failed to enter reproductive phase. Based on our results, the most suitable cultivar for cultivation in the region was Agamax.

    Keywords: Biomass yield, harvest index, oil yield, Protein yield