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مطالعات حفاظت گیاهان - سال سی و یکم شماره 1 (بهار 1396)

فصلنامه مطالعات حفاظت گیاهان
سال سی و یکم شماره 1 (بهار 1396)

  • تاریخ انتشار: 1396/04/02
  • تعداد عناوین: 18
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  • علمی - پژوهشی
  • حسین حمامی، محمدحسن راشد محصل، مهدی پارسا، محمد بنایان اول، اسکندر زند صفحات 1-12
    به منظور بررسی اثر روغن های گیاهی بر خصوصیات علف کش ستوکسیدیم یک سری آزمایش در دانشگاه فردوسی مشهد و پارک علم و فناوری خراسان رضوی در سال 1391 انجام شد. به منظور ارزیابی تاثیر روغن های گیاهی بر روی کشش سطحی آب مقطر، علف کش ستوکسیدیم و کارایی ستوکسیدیم در کنترل یولاف وحشی سه آزمایش به صورت فاکتوریل و بر اساس طرح کاملا تصادفی انجام شد. همچنین آزمایش دیگری روی تاثیر کاربرد روغن های گیاهی بر میزان پخشیدگی محلول پاششی بر اساس طرح کاملا تصادفی انجام شد. نتایج نشان داد که کاربرد روغن های گیاهی به استثنای روغن کرچک منجر به کاهش کشش سطحی آب مقطر شد. در حالی که نتایج تاثیر روغن های گیاهی بر کشش سطحی محلول علف کش ستوکسیدیم نشان داد که تمامی تیمارها به طور معنی داری موجب کاهش کشش سطحی شدند. اگر چه تمام روغن ها منجر به کاهش کشش سطحی شدند ولی بین کشش سطحی محلول ستوکسیدیم با روغن های گیاهی و کارایی کنترلی ستوکسیدیم رابطه منفی وجود داشت. نتایج رگرسیونی درصد خیس شدگی کاغذهای حساس با کشش سطحی نشان داد که بین میزان خیس شدگی کاغذهای حساس با کشش سطحی روغن های گیاهی یک رابطه منفی قوی وجود داشت. تمامی روغن های گیاهی باعث افزایش کارایی کنترل یولاف وحشی شدند.
    کلیدواژگان: پخشیدگی، روغن کرچک، کاغذ حساس به آب، کشش سطحی
  • رضا برازنده آق کاریز، ناصر پنجه که، محمد حاجیان شهری، سید کاظم صباغ، محمود بهزادی صفحات 13-19
    بیماری لکه غربالی درختان میوه هسته دار ناشی ازWilsonomyces carpophilus باعث ضعیف شدن درختان آلوده و کاهش کمیت و کیفیت محصول در اغلب مناطق جهان می شود. این تحقیق به منظور بررسی تنوع ژنتیکی این قارچ در استان خراسان رضوی با استفاده از نشانگر مولکولی rep-PCR انجام شد. از باغات هلو، شلیل، آلو، زردآلو و گیلاس شهرستان های قوچان، طرقبه-شاندیز، چناران، نیشابور، کلات، تربت حیدریه و مشهد نمونه برداری شد. برگ ها، سرشاخه ها و میوه های آلوده به آزمایشگاه منتقل شدند. قطعاتی از حد-فاصل بافت آلوده و سالم جدا و پس از ضد عفونی سطحی در تشتک های پتری حاوی محیط کشت های PDA، مالت آگار و آب آگار کشت و در انکوباتور با دماهای 18، 20 و 25 درجه سانتی‏گراد قرار گرفتند. قارچ های جدا شده پس از خالص سازی شناسایی شدند. تنوع ژنتیکی 20 جدایه قارچی جداسازی شده از درختان میوه هسته دار شهرستان های مختلف استان تعیین شد. تکثیر DNA ژنومی با استفاده آغازگرهای BOX A1R، ERIC2، ERIC1R، REP2-I و REP1R-I صورت گرفت. در مجموع 39 باند در محدوده 100 تا 5000 جفت باز تشکیل شد که از این تعداد 38 باند چند شکلی را نشان دادند. ماتریکس تشابه بین جدایه ها بر اساس ضریب جاکارد محاسبه و تجزیه کلاستر و رسم دندروگرام بر اساس UPGMA با استفاده از نرم افزار NTSYS.PC2.0 انجام شد. نتایج نشان داد که جدایه ها در سطح تشابه 69 درصد به 12 دودمان کلونی تقسیم شدند. با این نشانگر جدایه های قارچی شهرستان های کلات و چناران از نظر جغرافیایی و تا حدودی جدایه های قارچی آلو از نظر میزبانی از سایر جدایه های قارچی جدا شدند. همچنین با این نشانگر اکثر جدایه های قارچی زردآلو از سایر گروه ها جدا شدند.
    کلیدواژگان: بیماری لکه غربالی، نشانگر مولکولی
  • شهربانو صبوری، غلامحسین مروج، حسین صادقی نامقی، محبت محبی صفحات 20-28
    سوسک چهار نقطه ای حبوبات، Callosobruchus maculatus Fabricius، یکی از آفات مهم انباری در سراسر جهان است که از دانه های حبوبات مختلف مانند عدس، ماش، لوبیا، باقلا و خصوصا لوبیا چشم بلبلی تغذیه می کند و خسارت زیادی را به بار می آورد. در مطالعه ی حاضر، حساسیت حشرات کامل نر و ماده سوسک چهار نقطه ای حبوبات در برابر پرتودهی با امواج مایکروویو با فرکانس 2450 مگاهرتز در توان های بین 90 تا 900 وات در زمان های مختلف مورد ارزیابی قرار گرفت. آزمایش ها در قالب طرح کاملا تصادفی انجام شد. نتایج نشان داد که برای هر دو جنس نر و ماده و در همه ی توان های مورد مطالعه، با افزایش طول مدت پرتودهی، میزان مرگ و میر حشرات کامل افزایش می یابد. حساسیت افراد نر بیشتر از افراد ماده بود ولی بر اساس مقایسه ی شاخص متوسط زمان پرتودهی کشنده ی 50 درصد (LT50)، این تفاوت حساسیت معنی دار نبود. مقادیر LT50 در اثر توان های بین 90 تا 900 وات برای افراد نر به ترتیب بین 8/674 تا 4/41 ثانیه و برای افراد ماده به ترتیب بین 5/741 تا 2/47 ثانیه متغیر بود. بر اساس نتایج این بررسی، استفاده از امواج مایکروویو به ویژه در توان های بالا به عنوان یک جایگزین مناسب و ایمن برای کنترل سوسک چهار نقطه ای حبوبات در انبارهای مواد غذایی توصیه می گردد.
    کلیدواژگان: آفات انباری، امواج الکترومغناطیسی، پرتودهی، مرگ و میر، LT50
  • نصرت الله کریمی آرپناهی، سید وحید اسلامی، رحمت الله دهقان خلیلی صفحات 29-39
    خشکی از مهمترین و متداول ترین تنش های محیطی است که بر مراحل مختلف رشد و نمو گیاهان تاثیر می گذارد. به منظور بررسی اثر تنش خشکی بر خصوصیات رشدی علف هرز اویارسلام ارغوانی در سال 1392 در گلخانه تحقیقاتی دانشکده کشاورزی دانشگاه بیرجند دو آزمایش جداگانه در قالب طرح بلوک‏های کامل تصادفی در سه تکرار انجام شد. آزمایش اول شامل 6 سطح دور آبیاری (3، 6، 9، 12، 15 و 18 روز) و آزمایش دوم شامل 5 سطح آبیاری بر اساس درصد ظرفیت زراعی (5/12، 25، 50، 75 و 100 درصد) بود. نتایج نشان داد که بیشترین مقدار ارتفاع (76 سانتی متر)، سطح برگ (83/110 سانتی متر مربع)، تعداد ساقه (66/4 ساقه در گلدان)، وزن خشک اندام هوایی (132/4 گرم در بوته)، تعداد غده (66/7 غده در گلدان) و وزن خشک کل اندام زیرزمینی (435/4 گرم در بوته) در دور آبیاری 3 روز و کمترین میزان این صفات در دور آبیاری 18 روز حاصل شد. در آزمایش دیگر، بیشترین میزان این صفات در سطح شاهد (100 درصد ظرفیت زراعی) حاصل شد و با افزایش در تنش خشکی میزان صفات علف هرز بطور قابل ملاحظه ای کاهش یافت بطوری که در سطوح 25 و 5/12 درصد ظرفیت زراعی رشد علف هرز متوقف و گیاهچه ای تولید نشد. بطور کلی با افزایش شدت خشکی در هر دو نوع روش اعمال تنش، تمام خصوصیات رشدی علف هرز کاهش یافت. از آنجایی که در رژیم آبیاری 18 روزه و سطوح 25 و 5/12 درصد ظرفیت زراعی اندام های تکثیری مانند غده و ریزوم تولید نشد بنابراین به نظر می رسد استفاده از روش های کنترل غیر شیمیایی مانند مدیریت آبیاری می تواند در جهت کنترل این علف هرز موثر باشد، بدیهی است تکرار این تحقیق در محیط مزرعه جهت تایید این نتایج الزامی است.
    کلیدواژگان: تکثیر رویشی، دور آبیاری، محتوای رطوبت خاک، مدیریت غیر شیمیایی
  • عباس نصیری دهسرخی، حسن مکاریان، منوچهر قلی پور، حمید عباسدخت صفحات 40-51
    به منظور بررسی تاثیر امواج اولتراسونیک و پرایمینگ بذر بر خصوصیات سبزشدن بذر و رشد لوبیا چشم بلبلی در شرایط کاربرد علف کش خاک مصرف تریفلورالین، دو آزمایش مزرعه ای و گلخانه ای در سال 1393 در دانشکده کشاورزی دانشگاه صنعتی شاهرود در قالب طرح بلوک های کامل تصادفی با چهار تکرار انجام شد. تیمار های آزمایش شامل1- شاهد (عدم تیمار بذور) 2- تریفلورالین با مقدار توصیه شده (2 لیتر در هکتار) 3- تریفلورالین با مقدار کاهش یافته (یک لیتر در هکتار) 4- امواج فراصوت (اولتراسونیک) 5- امواج فراصوت+تریفلورالین با مقدار کاهش یافته 6- امواج فراصوت+تریفلورالین با مقدار توصیه شده 7- هیدروپرایمینگ 8- هیدروپرایمینگ+ تریفلورالین با مقدار کاهش یافته 9- هیدروپرایمینگ+تریفلورالین با مقدار توصیه شده بودند. در هر دو آزمایش، نتایج نشان داد که کاربرد ترکیبی امواج فراصوت+تریفلورالین با مقدارکاهش یافته باعث کاهش معنی دار درصد و سرعت سبز شدن بذور نسبت به کاربرد علف کش کاهش یافته به تنهایی گردید. در آزمایش مزرعه ای، تیمار امواج فراصوت باعث افزایش وزن خشک ساقه و برگ به ترتیب به میزان 27/25 و 58/29 درصد نسبت به شاهد شد. در آزمایش گلدانی، کاربرد امواج فراصوت باعث افزایش محتوای کلروفیل برگ به میزان 6/33 درصد نسبت به شاهد گردید. براساس نتایج این پژوهش، کاشت بذور لوبیا چشم بلبلی پیش تیمار شده با امواج فراصوت و هیدروپرایمینگ در خاک تیمار شده با تریفلورالین سبب کاهش درصد و سرعت سبز شدن بذور، وزن خشک اندام های هوایی و شاخص سطح برگ می گردد.
    کلیدواژگان: استقرار اولیه، ترفلان، رشد گیاهچه، رقابت
  • الهام کرمی، حجت الله محمدی، مصطفی حقانی صفحات 52-60
    این تحقیق طیدو سال (1391 و 1392) به منظور تعیین تعداد نسل و تغییرات جمعیت حشرات کامل خوشه خوار انگور،LobesiabotranaDen. & Schiff.،مخرب ترینآفت انگور در سی سخت (استان کهگیلویه وبویراحمد) انجام شد. سه باغ انگورانتخاب و در هر باغ، سه تله ی فرمونی در تاج درختان انگور در ارتفاع 5/1 متری نصب شدند.تله ها هر پانزده روز یک بار جایگزین شده، هر پنج روز یک بار بازدید و تعداد شب پره های به دام افتاده یادداشت می شدند. نتایج بیانگر وجود سه نسل در منطقه بود که شب پره های آن ها به ترتیب از اواسط فروردین تا اوایل خرداد (60 روز)، از اواخر خرداد تا اوایل مرداد (45 روز) و از اواسط مرداد تا اواخر شهریور (45 روز) پدیدار شدند. اوج پرواز نسل ها به ترتیب اواسط اردیبهشت، اواسط تیر و اواخر مرداد تا اوایل شهریور رخ داد. بازه ی زمانی ظهور شب پره های نسل اول نسبت به دو نسل دوم و سوم طولانی تر بود. علیرغم چندین نوبت مبارزه ی شیمیایی، جمعیت شب پره ها به ویژه در نسل اول همواره بالا بود که این امر بیشتر ناشی از بی اطلاعی باغداران نسبت به زمان مناسب مبارزه و مرحله و محل زمستان گذرانی آفت بود. در هر دو سال، بارندگی های بهاره در زمان ظهور حشرات کاملنسل اول، کاهش شدید شکار تله ها را به همراه داشت. زمان مناسب مبارزه ی شیمیایی در این منطقه را می توان با توجه به اوج پروازهای یافته شده و نوع آفت کشی که باید در مبارزه علیه آفت به کار گرفته شود، پیش بینی کرد.
    کلیدواژگان: اوج پرواز، خوشه خوار انگور، دوره ی پرواز، سی سخت، نوسانات جمعیت
  • عبدالله درپور سرخ سرایی، مهدی راستگو، ابراهیم ایزدی دربندی، کمال حاج محمدنیا قالیباف صفحات 61-73
    افزایش کارایی علف کش های پس رویشی نیازمند کاربرد مواد افزودنی به صورت اختلاط در مخزن و یا به کار رفته در ساختار فرمولاسیون می باشد. به منظور افزایش کارایی برخی ازعلف کش های پس رویشی چغندر قند، آزمایشی به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار در سال 1392 در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه فردوسی مشهد، اجرا شد. فاکتورهای آزمایش شامل؛ نحوه کاربرد علف کش (کاربرد یک مرحله ای و چند مرحله ای) ، نوع علف کش (کلریدازون+دسمدیفام (کلردس)، دسمدیفام+فنمدیفام+اتوفومسات (دسفنتو)، و کلریدازون+دسمدیفام+فنمدیفام+اتوفومسات (کلردس فن تو) و ماده افزودنی (عدم کاربرد ماده افزودنی، آمونیوم سولفات، آدیگور و سیتوگیت) بود.نتایج نشان داد که بیشترین میزان عملکرد ریشه چغندر قند (29/110 تن در هکتار) در نتیجه کاربرد چند مرحله ای کلر دس به همراه آدیگورو بیشترین میزان عملکرد شکر (10/16 تن در هکتار) در اثر کاربرد چند مرحله ای کلر دس فن توبه همراه آدیگور حاصل شد. همچنین تیمار کاربرد چند مرحله ای دس فن تو بدون ماده افزودنی کمترین میزان عملکرد ریشه و شکر را (به ترتیب با 07/50 و 57/7 تن در هکتار) در بین تیمارهای آزمایشی داشت. کاربرد چند مرحله ای کلردس به همراه سیتوگیت و همچنین کاربرد یک مرحله ای کلر دس فن توبه همراه سیتوگیت با کنترل کامل علف های هرز بیشترین تاثیر را بر تراکم و زیست توده کل علف های هرز داشتند. در مقابل،تیمارهای کاربرد یک مرحله ای و چند مرحله ای دسفنتو به همراه آمونیوم سولفات، کمترین تاثیر را بر تراکم و زیست توده کل علف های هرز داشتند. نتایج حاصل از برازش معادله کاهش هذلولی دو پارامتره نشان داد که در غیاب علف های هرز، بالاترین میزان عملکرد ریشه چغندر قند به ترتیب 62/104 و 41/101 تن در هکتار، و در صورتی که تراکم و زیست توده کل علف های هرز به 28/24 بوته در متر مربع و یا 13/479 گرم ماده خشک در متر مربع برسد، عملکرد ریشه چغندر قند 50 درصد کاهش خواهد یافت.
    کلیدواژگان: آدیگور، آمونیوم سولفات، دسمدیفام، سیتوگیت، کلریدازون
  • هادی زهدی، رضا حسینی، احد صحراگرد، امیر حسین محمدی صفحات 74-80
    کفشدوزک Oenopia conglobata contaminata (Menteries) (Col.: Coccinellidae) مهم ترین کفشدوزک فعال در باغ های پسته است. طعمه های جایگزین، نقش مهمی در پایداری جمعیت یک دشمن طبیعی در طبیعت دارند. در این بررسی فراسنجه های جدول زندگی این کفشدوزک به روش دو جنسی با تغذیه از مهم ترین طعمه های موجود در باغ پسته یعنی پوره های پسیل پسته، شته باقلا، شته یونجه و همچنین تخم شب پره ی آرد به همراه گرده ی ذرت به عنوان میزبان آزمایشگاهی مورد بررسی قرار گرفت. مطالعه ی جدول زندگی برای هر طعمه با 100 عدد تخم کفشدوزک انجام شد. کلیه آزمایش ها در دمای2±25 درجه ی سلسیوس، رطوبت نسبی 5±55 درصد و طول دوره ی روشنایی به تاریکی 8:16 ساعت انجام گرفت. داده های جدول زندگی طبق تئوری جدول زندگی دو جنسی مرحله سنی آنالیز شد. نتایج نشان داد که بیشترین میزان نرخ خالص تولید مثل و نرخ ذاتی افزایش جمعیت در رژیم غذایی پسیل پسته به میزان 87/290 نتاج ماده/فرد و 1559/0 بر روز بود و کمترین میزان این شاخص ها مربوط به رژیم غذایی تخم شب پره آرد بود(68/61 نتاج ماده / فرد و1103/0 بر روز). نتایج نشان داد که رژیم های غذایی پسیل پسته وشته باقلا در مقایسه با رژیم های غذایی شته یونجه و تخم شب پره ی آرد سبب افزایش شاخص های جدول زندگی وامید به زندگی کفشدوزک contaminata O. conglobata می شود و رژیم غذایی شته ای برای پرورش این کفشدوزک به منظور کنترل بیولوژیک پسیل پسته مناسب می باشند.
    کلیدواژگان: پسیل پسته، جدول زندگی، شته باقلا، شته یونجه، کفشدوزک
  • رضا محمد علی نژاد، سید غلامرضا موسوی صفحات 81-91
    به منظور بررسی اثر تداخل علف های هرز بر صفات مورفولوژیکی، عملکرد و اجزای عملکرد سه رقم گلرنگ و همچنین تراکم و وزن علف های هرز، آزمایشی به صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار در مرکز تحقیقات کشاورزی و منابع طبیعی استان خراسان جنوبی در سال 1392 به اجرا درآمد. تیمارهای آزمایش شامل سه رقم گلرنگ (گلدشت، پدیده و گلسفید) و شش تیمار تداخل علف های هرز (تداخل تا شروع رشد طولی ساقه، تا شروع تولید شاخه فرعی، تا شروع گلدهی، تا انتهای پر شدن دانه و تا پایان فصل رشد و شاهد یا کنترل کامل علف های هرز) بود. در این تحقیق صفات تعداد شاخه فرعی، قطر طبق، تعداد طبق در متر مربع، تعداد دانه در طبق، وزن هزار دانه، عملکرد دانه، عملکرد بیولوژیک، درصد و عملکرد روغن و تراکم و وزن خشک علف های هرز اندازه گیری شد. نتایج نشان داد که افزایش دوره تداخل تا پایان دوره رشد، منجر به کاهش عملکرد و اجزای عملکرد ارقام مختلف گلرنگ شد و در این بین رقم پدیده حساسیت کمتر و رقم گلدشت حساسیت بیشتری در برابر علف های هرز داشتند. رقم پدیده با 72/25 درصد و 46/70 گرم در متر مربع، بیشترین درصد و عملکرد روغن را به خود اختصاص داد. تداخل علف-های هرز تا پایان فصل رشد گلرنگ باعث کاهش معنی دار 6/35 درصدی عملکرد روغن در مقایسه با شاهد گردید. عملکرد دانه به غیر از وزن هزار دانه و درصد روغن، با سایر صفات گلرنگ همبستگی مثبت و معنی داری داشت. به طور کلی، کشت رقم پدیده و کنترل علف های هرز را با شروع مرحله تولید شاخه فرعی در زراعت گلرنگ در شرایط این تحقیق می توان پیشنهاد نمود.
    کلیدواژگان: درصد روغن، رقابت، شاخه دهی، طبق، وزن خشک
  • روح الله امینی، هادی عبدی، عادل دباغ محمدی نسب صفحات 92-104
    به منظور بررسی اثر روش های مدیریتی بر علف های هرز، عملکرد دانه و اجزای عملکرد ذرت دانه ای، آزمایشی در شهرستان روانسر استان کرمانشاه در سال 1393 به اجرا درآمد. این آزمایش در قالب طرح بلوک های کامل تصادفی با 10 تیمار و سه تکرار انجام شد. تیمارهای آزمایش شامل 1- کنترل شیمیایی بهمراه کنترل مکانیکی (کاربرد نیکوسولفورون 80 گرم ماده موثره در هکتار) + کولتیواتور 40 روز پس از سبزشدن) 2- کنترل شیمیایی دیگر بهمراه کنترل مکانیکی (کاربرد مخلوط توفوردی و ام سی پی آ(675 گرم ماده موثره در هکتار) + کولتیواتور40 روز پس از سبزشدن) 3- کنترل زراعی بهمراه کنترل مکانیکی (کشت ماشک گل خوشه ایدر پاییز + کولتیواتور40 روز پس از سبزشدن) 4- کنترل مکانیکی (کاربرد کولتیواتور در دو مرحله 25 و 40 روز بعد از سبزشدن) 5-کنترل زراعی (کشت مخلوط نخود با ذرت) 6- کنترل زراعی بهمراه کنترل زراعی دیگر (کشت ماشک گل خوشه ایدر پاییز + کشت مخلوط نخود با ذرت) 7- کنترل شمیایی بهمراه کنترل زراعی (کاربرد 2 مرحله علف کش گلایفوسیت (2050 گرم ماده موثره در هکتار) قبل از کشت + کشت مخلوط نخود با ذرت) 8- کنترل زراعی (کاربرد مالچ کلش گندم در پاییز به میزان 2625 کیلوگرم در هکتار) 9- کنترل زراعی (کاربرد مالچ کلش گندم در بهار به میزان 2625 کیلوگرم در هکتار) 10- وجین دستی در کل فصل رشد بودند. همچنین تیمار آلوده به علف هرز در کل فصل رشد نیز به عنوان شاهد در نظر گرفته شد. نتایج نشان داد که تیمارهای مختلف مدیریت علف هرز اثر معنی داری بر وزن خشک علف هرز، ارتفاع بوته، تعداد برگ در بوته، تعداد ردیف دانه در بلال، تعداد دانه در ردیف بلال، تعداد دانه در بلال و عملکرد دانه ذرت در واحد سطح داشتند. کمترین وزن خشک علف هرز در تیمار مخلوط توفوردی + ام سی پی آ+ کولتیواتور (72 گرم در متر مربع) و بیشترین مقدار آن در تیمارهای کشت مخلوط با نخود (440 گرم در متر مربع) و کاربرد مالچ کلش در پاییز (441 گرم در متر مربع) بدست آمد. بیشترین مقدار ارتفاع بوته، تعداد ردیف دانه در بلال، تعداد دانه در ردیف بلال و تعداد دانه در بلال در تیمارهای توفوردی + ام سی پی آ+ کولتیواتور، نیکوسولفورون+ کولتیواتور و ماشک گل خوشه ای+ کولتیواتور مشاهده شد. بیشترین عملکرد دانه ذرت به ترتیب در تیمارهای توفوردی + ام سی پی آ+ کولتیواتور (37/8 تن در هکتار)، نیکوسولفورون + کولتیواتور (5/6 تن در هکتار) و ماشک گل خوشه ای+کولتیواتور (3/6 تن در هکتار) به دست آمد. کمترین عملکرد دانه در تیمارهای کاربرد مالچ در پاییز (95/1 تن در هکتار)، کشت مخلوط با نخود (96/1 تن در هکتار) و ماشک گل خوشه ای+ کشت مخلوط با نخود (1/2 تن در هکتار) حاصل شد که با تیمار شاهد آلوده اختلاف معنی داری نداشتند. به طور کلی می توان نتیجه گرفت که کاربرد کولتیواتور در تلفیق با علف کش ها بیشترین کارایی را در مدیریت علف های هرز ذرت داشت.
    کلیدواژگان: کشت مخلوط، کولتیواتور، ماشک گل خوشه ای، مالچ، نیکوسولفورون
  • شهرام مهدی کرمی، ضیاءالدین باده یان، اکرم احمدی، فاطمه جعفری اصل صفحات 105-116
    قارچ Rhytima acerinum عامل بیماری لکه قیری در برگ درخت افرا می باشد. این تحقیق به منظور بررسی کاربرد اکسی تتراسایکلین، آمیکاسین و اریترومایسین در کنترل رشد میسیلیومی و جوانه زنی اسپور Rhytima acerinum عامل بیماری لکه قیری افرا پلت در شرایط آزمایشگاهی انجام گرفت. در این تحقیق برای کنترل رشد میسلیومی و جوانه زنی اسپور عامل بیماری لکه قیری افرا از آنتی بیوتیک های اکسی تتراسایکلین 10 درصد، آمیکاسین 5 درصد، اریترومایسین 5 درصد استفاده شد. پس از تهیه و خالص سازی پرگنه و تهیه اسپور قارچ، محیط کشت هایی تحت شرایط نور و تاریکی با آنتی بیوتیک تتراسایکلین10درصد در 4 غلظت 50 ، 100 ، 200، 500 میکرو لیتر و برای آمیکاسین 5 درصد و اریترومایسین 5 درصد در 4 غلظت متفاوت 100، 200 ، 400 ، 1000 میکرو لیتر در 100 سی سی آب مقطر، برای هر کدام تهیه گردید سپس این تحقیق با استفاده از آزمایش فاکتوریل در قالب طرح کاملا تصادفی و مقایسه میانگین داده ها با آزمون دانکن انجام گرفت. نتایج نشان داد که آنتی بیوتیک ها در ضریبAUFGC و رشد میسیلیومی قارچ دارای تفاوت معناداری بودند و جوانه زنی اسپور قارچ در شرایط نور و تاریکی دارای تفاوت معنی دار بود. نتایج نشان داد که از بین آنتی بیوتیک های مورد استفاده، اکسی تتراسایکلین 200 میکرولیتر در 100 سی سی آب مقطر بیشترین تاثیر را بر کنترل رشد میسلیومی و جوانه زنی اسپور قارچ Rhytisma acerinum داشته است. براساس نتایج بدست آمده می توان نتیجه گرفت که استفاده از آنتی بیوتیک ها در کنترل قارچها موثر است و نتایج این مطالعه می تواند در مدیریت جنگل و منابع طبیعی مفید واقع شود.
    کلیدواژگان: قارچ بیماری زا، Tar spot، ضریب AUFGS، مدیریت جنگل
  • میثم بابایی، سعید سعیدی پور صفحات 117-123
    در این تحقیق اثرات تراکم بذر و تیمارهای مختلف علف‏کش بر میزان کنترل علف‏های هرز و عملکردگندم مورد بررسی قرار گرفت. دو عامل تراکم بذر شامل سه سطح (180، 200 و 220 کیلوگرم در هکتار)و تیمارهای مختلف علف‏کش شامل سه سطح (عدم کنترل و کاربرد علف ‏کش‏ های آپیروسوتوتال)در این آزمایش مورد بررسی قرار گرفتند. آزمایش بصورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با چهار تکرار اجرا شد. نتایج نشان داد که تراکم و وزن خشک علف‏ های هرز به طور قابل توجهی تحت تاثیر تراکم کاشت قرار گرفت. این دو متغیر با افزایش تراکم کاشت در سطح آماری (P
    کلیدواژگان: رقابت گیاه زراعی، علف هرز، عملکرددانه، مقداربذر، وزن خشک علف های هرز
  • ناهید حیدرزاده، عصمت مهدیخانی مقدم، مرجان پاچناری صفحات 124-130
    به منظور شناسایی نماتدهای انگل گیاهی نهالستان های میوه در مناطق مختلف استان خراسان شمالی در طی سال های 1390 و 1391در مجموع 70 نمونه خاک از محیط اطراف ریشه نهال های استان جمع آوری گردید. نماتدها به روش الک و سانتریفیوژ استخراج و با استفاده از روش تکمیل شده دگریسه (De Grisse، 1969) تثبیت و به گلیسیرین منتقل شدند. پس از تهیه اسلایدهای دائمی، با استفاده از میکروسکوپ نوری خصوصیات ریخت شناسی و ریخت سنجی هر یک از نماتدها بررسی شد و با استفاده از منابع و کلیدهای شناسایی موجود، به شناسایی گونه های جدا شده اقدام گردید. در این بررسی 17 گونه متعلق به 13 جنس، مورد شناسایی قرار گرفت. این گونه ها عبارتند از : Aphelenchoides richardsoni، Aphelenchus avenae، Basiria graminophila، Boleodorus thylactus، Ditylenchus filimus، D. medicaginis، Filenchus cylindricaudatus، F. thornei، Geocenamus tenuidens، Helicotylenchus digonicus، H. pseudorobustus، Heterodera schachtii، Merlinius brevidens، Pratylenchus neglectus، P. thornei، Tylenchorhynchus thornei، Zygotylenchus guevarai.
    در میان گونه های گزارش شده، گونه های Pratylenchus neglectus، Merlinius brevidens و Boleodorus thylactus به ترتیب بیشترین فراوانی را داشتند. گونه Ditylenchus filimus برای اولین بار از ایران گزارش و شرح داده می شود.
    کلیدواژگان: خراسان شمالی، نماتدهای انگل گیاهی، نهالستان های میوه
  • مائده شهیری طبرستانی، کامران رهنما، محسن جهانشاهی، سعید نصرالله نژاد، محمدحسین فاطمی صفحات 131-141
    فعالیت ضد قارچی جدایه Trichoderma atroviridae (6022) در برابر قارچ های بیمارگر خاکزاد Macrophomina phaseolina و Sclerotinia sclerotiorum درشرایط آزمایشگاه، مورد بررسی قرار گرفت. در آزمون کشت متقابل، جدایه آنتاگونیست به سرعت، رشد قارچ های بیمارگر را متوقف نمود. متابولیت های فرار جدایه آنتاگونیست در کشت همزمان، 24، 48 و 72 ساعته در برابر قارچ های بیمارگر، اثرات بازدارندگی چشمگیری نشان دادند که با گذشت زمان و مسن تر شدن پرگنه قارچ تریکودرما، میزان تولید این متابولیت ها افزایش و در نتیجه اثرات بازدارندگی بیشتری مشاهده شد. غلظت های مختلف متابولیت های غیرفرار استخراج شده از محیط غذایی مایع و توده قارچی، توانستند به خوبی رشد میسیلیومی و تولید اسکلروت قارچ های بیمارگر را کنترل نمایند. متابولیت های غیرفرار استخراجی از توده قارچی، بازدارندگی بهتری نشان دادند و توانستند در غلظت 15 درصد به ترتیب تا 62/87 و 100 درصد از رشد M. phaseolina و S. sclerotiorum جلوگیری نمایند. از طریق چهار فرایند ساده آزمایشگاهی جهت استخراج (با حلال های آلی ان-هگزان و متانول؛ تکنیک Headspace و سوکسله توده قارچی) و با استفاده از دستگاه گاز کروماتوگرافی جرمی، 61 ترکیب متابولیت ثانویه شناسایی شدند که بیشتر آن ها از گروه آلکان ها بودند. کلیه ترپنوئیدهای شناسایی شده در این بررسی، فقط در تکنیک Headspace مشاهده شدند. از ترکیبات ضد قارچی شناسایی شده در این جدایه، 1- پنتانول، ایزوآمیل الکل و 2-اتیل-1- هگزانول؛ پالمیتیک اسید و استیریک اسید؛ بیس(2- اتیل هگزیل) فتالات و دی- ان اکتیل فتالات می باشند. وجود این ترکیبات، اثرات ضد قارچی متابولیت ثانویه را توجیه می نماید. این تحقیق برای اولین بار در ایران انجام می گیرد.
    کلیدواژگان: GC-MS، Macrophomina phaseolina، Sclerotinia sclerotiorum
  • شهلا فرامرزی، روزبه فرهودی صفحات 142-151
    در دو آزمایش جداگانه تاثیر عصاره آبی ماریتیغال با غلظت های (0، 5، 10 و 15 درصد حجمی) در پتری دیش و (0، 10، 20 و 30 درصد حجمی) به صورت محلولپاشی در گلدان بر رشد گیاهچه، جوانه زنی، میزان نشت پذیری غشا سلولی، فعالیت آنزیم های ساکارز سینتاز، آلفا آمیلاز، کاتالاز و غلظت مالون دی آلدهید علف هرز توق بررسی شد. نتایج نشان داد که افزایش غلظت عصاره آبی ماریتیغال سبب کاهش وزن تر گیاهچه و فعالیت آنزیم های آلفا آمیلاز و کاتالاز و افزایش غلظت مالون دی آلدهید در گیاهچه توق گردید؛ کمترین میزان فعالیت آنزیم آلفا آمیلاز و وزن تر گیاهچه تحت تاثیر عصاره 15 درصد ماریتیغال به ترتیب به میزان 1/2 نانومول بر گرم بذر بر دقیقه و 32/0 گرم مشاهده شد. بیشترین غلظت مالون دی آلدهید بافت گیاهچه توق در غلظت 15 درصد عصاره آبی ماریتیغال به میزان 4/0 نانو مول بر گرم وزن تر گیاهچه مشاهده شد. همچنین، در آزمایش گلدانی افزایش غلظت عصاره آبی ماریتیغال سبب کاهش وزن تر گیاهچه و فعالیت آنزیم کاتالاز و ساکارز سینتاز در توق گردید. کمترین مقدار فعالیت آنزیم کاتالاز و ساکارز سینتاز مربوط به غلظت 30 درصد به میزان 8/1 و 2 جذب پروتئین در 60 ثانیه مشاهده شد. بعلاوه، افزایش غلظت عصاره آبی ماریتیغال سبب افزایش تخریب غشا سلولی و غلظت مالون دی آلدهید در بافت گیاهچه ی توق شد. بیشترین غلظت مالون دی آلدهید که نشانگر تخریب غشا سلولی است در غلظت 30 درصد به میزان 93/0 نانو مول بر گرم وزن تر گیاهچه دیده شد.
    کلیدواژگان: آلفا آمیلاز، آنتی اکسیدان، ساکارز سینتاز، مالون دی آلدهید
  • آسیه خاتمی، محمدتقی ال ابراهیم، مهدی محب الدینی، رقیه مجد صفحات 152-165
    به منظور بررسی تاثیر علف کش ریم سولفورون (Titus 25% DF) به صورت پس رویشی در کنترل علف های هرز مزارع سیب زمینی، آزمایشی مزرعه ای در روستای شیخ کلخوران اردبیل در سال 1393 انجام شد. آزمایش به صورت فاکتوریل با تیمار شاهد در قالب طرح بلوک های کامل تصادفی با سه تکرار و دو فاکتور و با استفاده از رقم سیب زمینی مرسوم منطقه (آگریا) انجام شد. فاکتور اول، دزهای علف کش ریم سولفورون در شش سطح 5، 10، 20، 30، 40 و 50 گرم ماده موثره در هکتار و فاکتور دوم، زمان های کاربرد علف کش در مراحل مختلف رشدی سیب زمینی شامل مرحله سبزشدن سیب زمینی، استولون زایی و حجیم شدن غده بودند؛ همچنین دو تیمار بدون وجین (با علف هرز) و وجین کامل (بدون علف هرز)، به عنوان شاهد در نظر گرفته شد. تجزیه های آماری نشان داد که دزهای ریم سولفورون و زمان کاربرد آن تاثیر معنی داری بر زیست توده تاج خروس ریشه قرمز (L. Amaranthus retroflexus)، سلمه تره (Chenopodium album L.)، پیچک صحرایی (Convolvulus arvensis L.)، کل علف های هرز، تراکم کل علف های هرز و عملکرد کل غده داشت ولی اثرات متقابل آن معنی دار نشد. نتایج نشان داد که کاربرد دز 50 گرم ماده موثره در هکتار توانست زیست توده و تراکم کل علف های هرز را به ترتیب 63/94 و 38/55 درصد و زیست توده تاج خروس ریشه قرمز، سلمه تره و پیچک صحرایی را به ترتیب 50/95، 87/96 و 79/94 درصد نسبت به شاهد با علف هرز کاهش دهد. در بین زمان های کاربرد ریم سولفورون در مراحل مختلف رشدی سیب زمینی، مرحله سبز شدن سیب زمینی، زیست توده و تراکم کل علف های هرز را به ترتیب 39/79 و 52/42 درصد و زیست توده تاج خروس ریشه قرمز و سلمه تره را به ترتیب 93/72 و 92/82 درصد کاهش داد ولی زمان کاربرد ریم سولفورون تاثیر معنی داری برای زیست توده پیچک صحرایی نداشت. کاربرد ریم سولفورون به میزان 50 گرم ماده موثره در هکتار در مرحله سبز شدن سیب زمینی، بالاترین عملکرد غده در هکتار را ایجاد کرد.
    کلیدواژگان: تراکم علف هرز، دز - پاسخ، زیست توده، عملکرد غده
  • ناصر امانی فر صفحات 166-171
    لکه آجری برگ بادام مهمترین بیماری برگی بادام در ایران است. طی سال زراعی 92-1391 کنترل شیمیایی بیماری لکه آجری برگ بادام در حاشیه زاینده رود بررسی شد. برای این منظور اثر قارچ کشی تریفورین (ساپرول 30 درصد) به نسبت نیم در هزار در مقایسه با مخلوط بردو یک درصد روی دو رقم بادام مامایی و سفید، با زمان های مختلف سمپاشی بر اساس آهنگ رشد میوه بادام مقایسه گردید. نتایج نشان داد که دوبار سمپاشی با تریفورین در دو و چهار هفته بعد از ریزش گلبرگ ها، یک بار سمپاشی چهار هفته بعد از ریزش گلبرگ ها با تریفورین و دو بار سمپاشی با مخلوط بردو به ترتیب بهترین تیمارهای سمپاشی از نظر کاهش درصد آلودگی و شدت بیماری لکه آجری برگ بادام در دو رقم مامایی و سفید بودند. تمامی تیمار های سمپاشی در دو رقم بادام برای هر دو نوع سم از نظر کنترل بیماری تفاوت معنی داری با درختان شاهد داشتند. درصد آلودگی و شدت بیماری روی بادام رقم مامایی بیشتر از رقم سفید بود. به طور کلی می توان گفت تریفورین از نظر کاهش درصد آلودگی و شدت بیماری لکه آجری برگ بادام موثرتر از مخلوط بردو است.
    کلیدواژگان: زمان سمپاشی، لکه آجری برگ بادام
  • سمیرا گودرزوند چگینی، حبیب عباسی پور، جابر کریمی، علیرضا عسکریان زاده صفحات 172-178
    شب پره مینوز برگ گوجه فرنگی، Tuta absoluta (Meyrick)، یکی از آفات مهم گیاهان خانواده Solanaceae خصوصا گوجه فرنگی در دنیا و ایران محسوب می شود. استفاده بیش از حد از حشره کش های شیمیایی به سرعت منجر به بروز مقاومت آفت می شود. استفاده از ترکیباتی با منشا طبیعی مانند اسانس های گیاهی در کنترل آفت جایگزین مناسبی برای حشره کش های شیمیایی محسوب می شوند. در این تحقیق، سمیت تنفسی اسانس زیره سیاه روی مراحل تخم، لارو سن دوم و حشره کامل مورد بررسی قرار گرفت. اسانس گیاه با استفاده از دستگاه کلونجر (Clevenger) به روش تقطیر با آب استخراج شد. غلظت های مختلف اسانس در دامنه بین20 تا 100، 3 تا 7 ، 1/0 تا 1 و 5/0 تا 1 میکرولیتر بر لیتر هوا به ترتیب روی مراحل تخم، لارو سن دوم درون تونل برگ، لارو سن دوم به صورت مستقیم و حشره کامل هر کدام با سه تکرار به همراه شاهد آزمایش شد و میزان تلفات بعد از 48 ساعت محاسبه گردید. نوع و میزان درصد ترکیبات گیاهی در هر کدام از اسانس ها با استفاده از دستگاه GC/MS تعیین گردید. نتایج نشان داد که با افزایش غلظت اسانس، مرگ و میر هم افزایش یافت. تجزیه و تحلیل پروبیت داده ها نشان داد میزان LC50 برای تخم، لارو سن دوم درون برگ، لارو سن دوم بیرون برگ و حشره کامل به ترتیب 24/44، 652/4، 335/0 و 624/0 میکرولیتر بر لیتر هوا بود. در اسانس زیره سیاه ترکیبات Benzaldehyde، 4- (1- methylethyl) – (c) (29/21 درصد) و P- cymene (02/18 درصد) جزو ترکیبات شیمیایی عمده بودند. نتایج حاصل نشان داد اسانس زیره سیاه پتانسیل بالایی برای کنترل شب پره مینوز گوجه فرنگی در محیط های بسته دارد و برای حفاظت از محیط زیست و سلامت کاربران توصیه می شود.
    کلیدواژگان: دز کشنده، کلونجر، گیاهان دارویی
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  • H. Hammami, M. H. Rashed Mohassel, M. Parsa, M. Bannayan Aval, E. Zand Pages 1-12
    Introduction
    During last century, population explosion has been pressing man to produce more supplies of food by consuming more energy in agroecosystems like applying chemical management strategies. herbicides have increasingly become a key component of weed management programs. In Iran, using herbicides led to increasing wheat yield about 20% and 22% in rainfed and irrigated farms respectively (20). Nonetheless, herbicides have also a negative impact on environment. A tool for reducing the herbicide usage which allows to decreasing their cost and side effects is the use of adjuvants. They increase the effectiveness of the post-emergence herbicides. Some adjuvants have toxic effects on living organisms such as Polyethoxylated tallowamine adjuvants that they are very toxic in fairy shrimp (Thamnocephalus platyurus) (6). Vegetable oils are not phytotoxic and likely are degraded and metabolized quickly in the environment (8). Sethoxydim is an acetyl coenzyme A carboxylase (ACCase) inhibitor that is considered to be a key enzyme in lipid biosynthesis. Similar to other foliar applied herbicides, it need to be associated with an adjuvant for more effective control. Vegetable oils can be developed characteristics of sethoxydim solution such as surface tension and spry drop diffusion. Therefore, the objective of this research is to determine the effect of vegetable oils on the surface tension, diffusion and efficiency of sethoxydim to control wild oat (Avena ludoviciana Durieu.).
    Materials and Metods: To evaluate the effect of vegetable oils on properties of sethoxydim solution, a series of experiments were separately conducted at Ferdowsi University of Mashhad and Khorasan Science and Technology Park in 2012. For evaluating the effect of vegetable oils on surface tension of distilled water and sethoxydim solution and the sethoxydim efficiency on wild oat control, three experiments were conducted as factorial based on completely randomized design. In other experiment the vegetable oils application on diffusion of sethoxydim was conducted also based on a completely randomized design. A K100 tensiometer was used to measure the surface tension of water and sethoxydim solution containing vegetable oils. For measuring the diffusion of sethoxydim solution containing vegetable oils, water sensitive paper was used. The surface changing color was evaluated by using MIP software. Wild oat seeds were collected from plants in the field near the research greenhouse at Ferdowsi University of Mashhad, Iran. They were dehulled and placed in 11 cm diameter Petri dishes on top of a single layer of filter paper (Whatman International, Maidstone, UK). Then, 10 mL of 0.2% KNO3 solution were added to each Petri dish and the seeds were incubated for 48 h at 4–5°C in the dark. The seeds then were germinated under temperature and relative humidity control conditions in the dark (16 h at 20°C and 8 h at 10°C, with 45% and 65% relative humidity, respectively). By this method, 92–98.5% of the seeds germinated. Ten germinated seed were planted in each 1.5 L plastic pot that was filled with a mixture of sand, clay loam soil, and peat (1:1:1; v/v/v). The pots were sub irrigated every 3 days. The seedlings were thinned to four per pot at the one leaf stage and 40 mL of a water-soluble N: P: K (20:20:20) fertilizer, at a concentration of 3 g of fertilizer per liter of tap water, were supplied to each pot.
    Results And Discussion
    The results showed that the use of vegetable oils except castor oil caused reduction in the surface tension of distilled water. About the surface tension of the sethoxydim solution, all vegetable oils significantly reduced surface tension. There is anegative relationship between surface tension of sethoxydim solution and efficiency of sethoxydim. Regression analysis results of the surface tension and spray deposit distribution on sensitive paper percent showed strong negative relationship them. Effects of adjuvants on herbicide surface tension have been showed by other researches. As judged by the ED50 and relative potential showed in table 3, all vegetable oils led to increased herbicide efficiency. Using adjuvants led to increasing performance of herbicide.
    Conclusion
    Using of vegetable oil can be reduced needed sethoxydim for controlling wild oat. Reducing surface tension of herbicide solution can be known as a main reason for improvement of herbicide efficiency in the presence of vegetable oils. Low surface tension lead to more distribution of herbicide solution on leaf surface and eventually increased herbicide absorption.
    Keywords: Castor oil, Distribution, Surface tension, Water sensitive paper
  • R. Barazandeh Aq Kariz, N. Panjehkeh, Mohammad Hajian Shahri, S. K. Sabbagh, M. Behzadi Pages 13-19
    Introduction
    Shot hole disease of stone fruit trees resulted from Wilsonomyces carpophilus can weaken the trees and reduce the quantity and quality of the crops worldwide particularly in semi-arid regions. Coryneum blight or shot hole disease infects all the stone fruit trees including peach, nectarine, apricot, sour cherry, plum, cherry, and almond. One of the most important strategies to manage any plant disease is to use resistant cultivars. In this way, it is very important to have knowledge about the status of genetic diversity and to determine the relationship between isolates of the causal agent fungus. The main objective of the present research was to study the genetic diversity of W. carpophilus in Khorasan Razavi province using the rep-PCR molecular fingerprinting method.
    Materials And Methods
    Sampling was performed from peach, nectarine, plum, apricot and cherry orchards of Quchan, Torqabeh, Shandiz, Chenaran, Neishabur, Kalat, Torbat Heidarieh and Mashhad during spring and summer of 2012 and 2013. Mono-conidial isolates were recovered from infected leaves, fruits, and twigs of different parts of orchards. Infected collected leaves, twigs, and fruits were transferred to the laboratory. By using techniques of Klimesova and Prasil (1989) and Mehta (1998) from the cut parts between infected and healthy tissues of each isolate, cuts of 2-3 mm from leaf, fruit and twig were prepared by the scalpel. These pieces were surface sterilized with 1% sodium hypochlorite liquid about 1 to 3 minutes based on the thickness of tissue. Then, the samples were cultured on PDA, MEA, and WA media and incubated at 18, 20, and 25 °C. The isolated fungi were purified and identified. The research was performed on 20 fungal isolates collected from different stone fruit trees. Genomic DNA was amplified using BOX A1R, ERIC2, ERIC1R, REP2-I, and REP1R-I primers. Thirty-eight of 39 fragments amplified were polymorphic for 100 to 5000 base pairs. Similarity matrix between isolates was calculated based on Jacquard Coefficient and cluster analysis and construction of dendrogram were done based on UPGM using NTYSIS.PC 2.0 software.
    Results And Discussion
    From 39 amplified bands, 38 bands (97.5%) showed polymorphism. The molecular weight of amplified DNA fragments was between 100 to 5000 bp. Based on analysis of banding pattern of REP primer set, isolates of W. carpophilus were categorized into 12 groups at the 69% similarity level. The most genetic similarity of isolates (94%) was between AK (apricot of Kalat) and PK (peach of Kalat) and the least genetic similarity of W. carpophilus isolates was between AQ (apricot of Quchan), AN (apricot of Neishabur), AC (apricot of Chenaran), PlM (plum of Mashhad), PM2 (peach of Mashhad number 2), and CC (cherry of Chenaran) with the other isolates. Based on the results of this study rep-PCR could separate isolates of W. carpophilus very well and also could separate similar isolates and hosts which have the close genetic relationship. Similar results were obtained by Edel et al. (1995) and Jedryczka et al. (1999). Edel et al. (1995) compared three different molecular methods for characterization of Fusarium oxysporum strains. The marker also separated isolates of Kalat and Chenaran geographically and to some extent isolates of plum in terms of hosting from the other isolates. Toda et al. (1999) in their study, about the investigation of genetic correlation among and within different isolates of Rhizoctonia solani by rep-PCR divided the 41 isolates into 7 groups which indicate considerable genetic diversity among isolates. Also, Karimi et al. (2010) in their study about the investigation of genetic diversity of Sclerotinia sclerotiorum at 64% similarity level, divided the isolates into 7 groups and separated most of the isolates geographically.
    Conclusion
    The results obtained in this study indicated that rep-PCR is a practical, rapid, and accurate technique for separation of W. carpophilus isolates. Considering the high genetic diversity observed in the population of this fungus, making attempts to plant cultivars with high resistance and resistant genes can largely prevent the outbreaks and intensity of the pathogen. Therefore, further researches in this area can be placed in breeding, production and reproduction of cultivars with particular resistance programs against shot hole disease. The present research study is a prelude to solving problems related to this important disease.
    Keywords: Molecular Marker, Shot Hole Disease
  • S. Saboori, G. Moravvej, H. Sadeghi Namaghi, M. Mohebbi Pages 20-28
    Introduction
    The cowpea seed beetle (Callosobruchus maculatus F.) is one of the most injurious insects infesting a wide range of leguminous stored seeds such as Lens culinaris, Vigna radiata, Vicia faba and Vigna unguiculata (1). This insect also causes secondary infestation during pulse storage, and may cause total loss within three months. The bruchids can cause heavy losses in terms of both quantity and quality (4). Heavy infestations of bruchids can cause heating of commodity, which results in quality loss, and mould growth. Currently, the control strategies of stored product insect pests have exclusively relied upon application of fumigants and protectant synthetic insecticides. Chemical control of pests has led to insecticide residues in stored products and insecticide-resistant insect populations (3, 6). Therefore, there is a need for the ecologically benign methods to control cowpea weevil on chickpea. High temperature application has been used to satisfactorily disinfest stored commodities by various technologies. Microwave radiation is one of the most promising biorational pest management tools for farm stored grain and grain processing industries (29). Microwave is a type of electromagnetic energy that provides rapid heating. It appears that high temperatures in a short time period may be lethal to many stored product pests. The present study aimed to assess the lethal effects of microwave radiation on adults of cowpea seed beetle in stored pulses.
    Materials And Methods
    The population of C. maculatus was originally collected from Laboratory of Entomology at Ferdowsi University of Mashhad, Iran. The cowpea weevils were reared on chickpea, in a growth chamber at temperature of 28 ± 2 ºC, relative humidity of 60 ± 5 % in the dark. Male and female beetles were treated separately with 2450 MHz at power levels of 90-900 W over a range of irradiation periods from 20 to 960 seconds. Corrected mortality data were subjected to two-way factorial analysis of covariance (ANCOVA) in which the microwave power and insects’ sex were regarded as independent categorial factors and irradiation period as covariate using SPSS Version 16 software. Prior to the ANCOVA test, Levene's test for equality of variances was performed to examine the assumptions for ANCOVA. Moreover, at each radiation power, the values of median lethal time (LT50), i.e., microwave irradiation period needed for the death of 50% insect population, and 90% lethal time (LT90) with 95% confidence limits were estimated separately for male and female beetles by subjecting mortality data to the maximum likelihood program of probit regression analysis using POLO-PC software. This program has a provision for control mortality.
    Results And Discussion
    The results indicated that the mortality rates of both male and female adults increased as the exposure period and/or the power of radiation increased. When microwave power levels increased, the time elapsed to achieve maximum lethal effect decreased; this was implied by the results showing maximum mortality achievement in 960 and 80 seconds at 90 W and 900 W, respectively. Male beetles were more susceptible than females, but this difference was not significant based on the LT50 ratio. The LT50 values for the power levels between 90-900 W varied between 674.8 - 41.40 seconds for males and 741.5 - 47.2 seconds for females. The probit analysis showed that the slope values of mortality - exposure time regression lines were in the range of 3.23 - 5.51. According to the likelihood ratio test of parallelism, the slopes of probit mortality regressions differed significantly among various microwave power levels. However, further likelihood ratio test between the paired combinations concerned revealed that the slopes of probit mortality lines differed significantly only between those of 90 and 900W levels. The present results are in agreement with those of Singh et al. (2012) who worked on Callosobruchus chinensis (26). Also, Sadeghi Nasab et al (2004) working on the effect of microwave radiation on three stored product pests, found similar results (25).
    Conclusion
    The results from our study showed that microwave radiation has a potential to kill insects in stored beans. It was observed that at certain constant power levels, the mortality of beetles increased as the microwave exposure time elongated and vice-versa. Although this strategy can control insect population in stored beans in a short time whilst deserting no chemical residue on food products, the adverse effects of microwave radiation on nutritional quality of food products and seed germination should be investigated. Further research is also recommended to improve methodology for practical disinfection of stored pulses.
    Keywords: Stored product pests, Electromagnetic waves, Radiation, Mortality, LT50
  • N. Karimi Arpanahi, S.V. Eslami, R. Dehghan Khalili Pages 29-39
    Introduction
    Drought is one of the most important and common environmental stresses in the country, which affect different stages of plant growth and development. Drought can affect plants growth in various ways, thereby reduces and delays germination, and decreases shoot growth and dry matter production. In the case of high water stress, it results showed great reductions in photosynthesis and disruption of the physiological processes, as well as growth stop and eventually plant death.Purple nutsedge (Cyperus rotundus L.) has been listed as the world’s worst weed based onits worldwide distribution (92 countries) and interference with over 50 crops. It causes high yield losses in fruiting vegetables and cucurbits in eastern and southeastern parts of Iran, where drought stress is a common phenomenon. Therefore, it is of utmost importance to understand the response of this noxious weed species to drought stress.
    Materials And Methods
    In order to study the effect of drought stress on growth and distribution of purple nutsedge, two separate experiments were carried out in a randomized complete block design with three replications in the Research Greenhouse at Birjand University in 2013. The first experiment consisted of 6 irrigation interval levels (3, 6, 9, 12, 15 and 18- day irrigation intervals) and the second one were 5 irrigation levels based on field capacity (12.5, 25, 50, 75 and 100 % FC).
    Results And Discussion
    ANOVA results of both experiments showed that all growth characteristics of purple nutsedge were affected by drought stress. The results of irrigation interval stress experiment showed that the maximum height (76 cm), leaf area (110.83 cm2), stem number (4.66 stemperpot), shoot dry weight (4.132 gr per plant), tuber number (7.66 tuber per pot) and total underground organs dry weight (4.435 gr per plant) were observed in 3- day irrigation interval. Also, the lowest amount of these characteristics was obtained in 18- day irrigation interval. The influence of increasing the irrigation intervals up to 18 days was obvious in reducing weed morphological characteristics. With longer irrigation intervals, weed height declined severely, and the greatest reduction in plant height (62.43% comparison to control) was obtained from 18- day irrigation interval. Irrigating plants at 12, 15 and 18- day intervals decreased 66.15, 77.84 and 88.96% in weed leaf area compared to 3- day irrigation interval (control), respectively. The maximum reduction in stem number (78.54% relative to control) was observed at 18- day irrigation interval. Increasing drought stress levels significantly decreased 62.95, 76.27, 97.57% shoot dry weight under 12, 15 and 18- day irrigation intervals regimes, respectively. . Also, increaseddrought levels, significantly reduced weed tuber number, so that no tuber produced at 18- day irrigation interval. Moreover, underground organs dry weight decreased 51.91, 65.68 and 88.48% at 12, 15 and 18- day irrigation intervals compared to control, respectively. In other experiment, the maximum height (70.33 cm), leaf area (116.33 cm2), stem number (7 stem per pot), shoot dry weight (3.701 gr per plant), tuber number (5.66 tuber per pot) and total dry weight of underground organs (513/3 gr per plant) were obtaind at 100% field capacity (control).. The results showed that plant height decreased with increasing drought levels, so the minimum plant height was observed at 25 and 12.5% FC. Increasing drought stress reduced leaf area 68.59 and 91.61% at 75% and 50% FC compared to control, respectively. The maximum reduction in stem number was observed at 25 and 12.5% FC. The weed dry matter decreased 52.90 and 88.05% compared to control at 75 and 50% FC, respectively. Tuber production was severely affected by soil water content reduction, so that no tuber was produced at 25 and 12.5% FC. Dry weight of underground organs in purpule nutsedge decreased 39.48 and 79.24% at 75 and 50% FC compared to control, respectively.
    Conclusion
    Overall different levels of drought stress in both experiments, were reduced all weed growth characteristics. Since reproductive organs such as tuber and rhizome were not produced at 18- day irrigation interval regime and 25 and 12.5% FC,, therefore it seems non-chemical control methods such as irrigation management can be effective to control this weed. Obviously repeating this research in field conditions is required to confirm these results.
    Keywords: Vegetative reproduction, Irrigation interval, Soil moisture content, Non chemical management
  • A. Nasiri Dehsorkhi, H. Makarian, M. Gholipoor, H. Abbasdokht Pages 40-51
    Introduction
    Improving the rate of germination and crop growth at the early growing stagescan reduce weed damage via increasing crop competitiveness. Trifluralin is a pre emergence herbicide that is incorporated with soil to prevent weed emergence and seedling growth. It inhibit microtubule assembly in cells . Seed priming cause to initiate the repairing system for membrane and the metabolic preparation for germination through controlling water absorption rate of seed. As a result, the germination capability and resistance to unfavorable conditions of seed can be promoted obviously using seed priming. Ultrasound is defined as acoustic waves at frequencies greater than 20 kHz that can be an effective method to improve germination and growth characteristics of plants . There is no knowledge about the effect of ultrasonic waves and seed priming on the emergence and growth of cowpea (Vigna sinensis) under soil application of trifluralin. So the objective of this research was to study the effect of ultrasonic waves and seed priming on the emergence and growth of cowpea under soil application of trifluralin.
    Materials And Methods
    Field experiment was conducted at the research field of Shahrood University (latitude of 36° 25 'N and longitude of 54° 57' E with an elevation of 1345 m) as randomized complete block design with four replications in during the growing season of 2014-2015. The field soil was silty clay loam in texture, having pH 7.8, EC 3.9 ds m-1, 0.75% of organic carbon, 0.04% N 6.4 and 320 ppm of available P and K. Nine treatments were 1- control, 2- recommended herbicide dose (trifluralin 2 L ha-1), 3- reduced herbicide dose (trifluralin 1 L ha-1), 4- ultrasonic waves (ultrasound), 5- ultrasonic waves reduced herbicide dose, 6- ultrasonic waves recommended herbicide dose, 7- hydro-priming, 8- hydro-priming reduced herbicide dose and 9- hydro-priming recommended herbicide dose. For hydro-priming treatment, the seeds were treated with water before sowing for 7 h. About ultrasonic treatment, the seeds before sonication (for 6 minutes) treated with water for 7 h. Trifluralin (Treflan, EC48%) applied in recommended dose (2 L ha-1) and reduced herbicide dose (1 L ha-1) as immediate mixed with soil before planting. The plots were 24 m2 with 4 sowing rows and 6 m long. Seeds were placed at 3 to 5 cm depth in each row at during the second week of June in 2014. Number of emerged seedlings in two middle rows of were daily counted until seedling establishment became stable. Emergence percentage and rate of cowpea were calculated. Sampling was done at 55 days after planting. All samples were transferred to the laboratory, leaves and stem were separated,dried into oven at 70 ºC for 72 h and weighted. Chlorophyll content, relative water content, leaf and shoot dry weight and plant height of cowpea were measured for all treatment
    The second experiment was conducted at the greenhouse as randomized complete block design with four replications in 2014. The treatments were exactly similar to the field experiment. Germinated seeds were recorded every 24 h for 16 days. Then, the plants were removed from each pot and transferred to the laboratory. Root, leaves and stem were separated and afterwards all samples were dried into oven at 70 ºC for 48 h and weighted. Seedling vigor index, chlorophyll content, shoot and root length, weight of root, leaf and shoot, number of leaf and leaf area index were measured for all treatment. Chlorophyll content was estimated using chlorophyll meter (SPAD-502, Konika-Minolta Co). Statistical analyses of data were performed with statistical software MSTATC. Significant differences between means refer to the probability level of 0.05 by LSD test.
    Results And Discussion
    The results showed that the ultrasonic treatment increased the dry weight of stem and leaves by 25.27 and 29.58 % as compared with the control treatment respectively. Mirshekari et al. (34) reported that when seeds were primed with ultrasonic irradiation for 5 min, seedling dry weight and leaf chlorophyll content of yarrow increased by 70% and 33.6% than control respectively. Marghaeizadeh et al. (33) reported that application ultrasonic waves increased the chlorophyll content of Carum copticum (L.) C. B. Clarke in comparison to control. Our results suggested that at both experiments the combined use of ultrasonic waves reduced herbicide dose decreased the percentage and rate of emergence significantly in comparison to herbicide application alone. The application of ultrasonic waves reduced herbicide dose led to a reduction in the percentage and rate of emergence by 64.83 and 68.13% in comparison to reduced herbicide application alone, respectively. Also the combined use of priming reduced herbicide dose decreased the percentage and rate of emergence by 50.4 and 53.8 % in comparison to reduced herbicide application alone respectively. The major effects of dinitroanaline herbicides are on plant root growth, which they stop by interfering with mitosis and preventing normal cell division and cell wall formation (38, 35). It seems that hydro priming technique and ultrasonic irradiation with improving seed germination and seedling early growth under soil-incorporated trifluralin herbicide can led to more and faster absorption of herbicide by seedling and more damage to them than control.
    Conclusion
    Our results showed the ultrasonic waves and priming accelerates the seed germination and root length and ultimately resulted in improving biomass and growth of cowpea seedling. Also data presented in this research suggested that pre-treated of cowpea seeds with ultrasonic waves and hydro priming can reduce some plant parameters like percentage and emergence rate of seeds, shoots dry weight, leaf area index and etc. in soil treated with trifluralin herbicide.
    Keywords: Primary establishment, Treflan, Seedling growth, Competition
  • E. Karami, H. Mohammadi, M. Haghani Pages 52-60
    Introduction; The European grapevine moth, Lobesia botrana (Denis and Schiffermüller, 1776), (Lep.: Tortricidae) is the most serious insect pest of vineyards in Sisakhat. It is a polyvoltine pest and can complete two to four generations in one year depending on environmental conditions. The larvae penetrate berries very quickly after egg hatching and damage the grapes directly by feeding and webbing or indirectly by favoring the gray mold. Its control is necessary to harvest crop in commercial vineyards. In spite of two to four times of chemical control in this region, its population is always high especially in the first generation which is mainly rooted in inappropriate chemical spraying time. In the present study, it was attempted to optimize spraying time by determination of number of generations, population fluctuation and density of adult moths through sex pheromone-baited traps.
    Materials and Methods; This research was done in two consecutive years (2012 and 2013) using sex pheromone traps in vineyards of Sisakht, Kohgiluyeh and Boyer-Ahmad province. Three vineyards selected which were 1.5 kilometers away from each other and three traps installed in each vineyard within tree canopy at height of 1.5 meters above the ground. the pheromone trade mark was Scentomos and traps were delta type. Traps in each vineyard were more than 150 meters away from each other. Traps were being replaced once every 15 days and inspected once every 5 days. Trapped moths were being removed with a forceps and recorded in each inspection. This trend continued from late March to late September when no longer moth trapped. Finally mean of trapped adults were calculated and plotted against time to determine generation numbers, flying periods and flight peaks.
    Results and Discussion; The results of different vineyards and years coincided and confirmed each other well. Pest population graph had three distinct ups and downs during each season which was indicative of three generations per year. The first moths were trapped at the end of March and the beginning of April. Then, number of trapped moths increased until late April and continued in a steady state up to May 20th when it started to decrease. For a long part of June, number of trapped moths was averagely less than one moth per trap per night. From June 20th, the trapped moths increased again and reached its peak very soon at early July and decreased gradually up to late July. Late July to early August, trapped moths were less than one moth per trap per night. Early August onwards, trapped moths started to increase once again and reached its peak nearly about late August. Then it decreased up to 25th September when no moth was trapped any longer. Flight peaks of generations occurred early May, early July and late August, respectively. Flying periods of second and third generations were equal but was shorter than flying period of first generation which makes the control of first generation more difficult. In spite of chemical controls, population of the moth was high especially in first generation which could be attributed to chemical spraying at inappropriate time and insufficient knowledge of farmers about the pest overwintering stage and places. Spring rainfalls during emergence of the first generation reduced the trapped moth adults severely which have to be considered in the interpretation of the adult population fluctuation. The optimal spraying time could be adjusted based on the adults population fluctuation and type of the insecticide used. As usual, the insect growth regulators should be applied before egg laying or egg hatching. Contact and ingested insecticides (e.g., organophosphates, pyrethroids, and carbamates) should be applied after egg hatching to kill larvae as they emerge from eggs. Since the pesticides which are used in this region are mostly contact organophosphates or pyrethroids, the peak flights could be considered as the optimal spraying time. Since first generation emerge gradually and its population is high, optimizing the first chemical control is more critical and may decrease the necessity of next spraying. Due to spring rainfalls during May, any chemical spraying against the first generation should be done with considering the weather forecasting.
    Conclusions; In this region, European grapevine moth adults emerged from early April to late May (60 days), mid-June to late July (45 days) and early August to late September (45 days), respectively. Flight peaks of the moth generations occurred early May, early July and late August, respectively. The moth population was high especially in first generation which implies that control of first generation is necessary. Flying period of the first generation was much longer than that of the other two generations which makes the control of first generation population more difficult. However, the chemical spraying time could be adjusted based on the mentioned peak flights and type of insecticide which have to be applied in this region.
    Keywords: Flight peak, Flying periods, Grapevine moth, Population fluctuation
  • A. Dorpoor, M. Rastgoo, E. Izadi Darbandi, K. Haj Mohammadnia Ghalibaf Pages 61-73
    Introduction
    Increasing the environmental concerns emerged from the extensive use of herbicides have caused to work and introduce new approaches for their application by weed scientists. Nonetheless, weeds limit crop production especially when herbicides are removed from the weed management strategies. Optimizing herbicide doses, by increasing farmer’s knowledge about various options of herbicide application, is one of the most important strategies for reducing herbicide application. Tank-mixed herbicides, adjuvants, and split application of herbicide are more interesting, users friendly, and effective to implement this approach. Post-emergence herbicides require adjuvants to be tank-mixed or built into the formulation to enhance their performance. Utilizing these methods is very essential for crops which are very weak competiveness against weed, because of herbicides application is a common method in them. Sugar beet is an important crop grown in the most cultivation areas of Iran under cultivation about 82.5 thousand hectares over average yield 42 ton ha-1. This study was done to increase the performance of some post-emergence herbicides for controlling weeds in sugar beet using adjuvants, tank-mixed herbicide, as well as herbicide split-applied herbicide treatments.
    Materials And Methods
    A factorial experiment based on randomized complete block design with three replications was conducted at the research field of Ferdowsi University of Mashhad (985 m altitude, longitude 59˚ 28´ and latitude 36˚ 15´) in 2013. The factors included the method of herbicide application (full and split application), herbicides (chloridazon (5 Kg ha-1) plus desmedipham (6 L ha-1), desmedipham plus phenmedipham plus ethofumesate (3 L ha-1) and chloridazon (5 Kg ha-1) plus desmedipham plus phenmedipham plus ethofumesate (3 L ha-1)), and adjuvants (Non-adjuvant, Adigor (%1.5 v/v), Citogate (%0.2 v/v) and Ammonium sulfate (%0.5 v/v)). Furthermore, two control treatments were considered as weed free and weed infested for each replication. Herbicides were applied with a backpack sprayer equipped with 8002 flat fan nozzles that calibrated to deliver a spray volume of 400 L ha-1 at 275 kPa. Commercial sugar beet seeds, ‘005’ Monogerm provided from Improvement Research Institute of sugar beet, Karaj were planted on April 25 by hand to the depth 2 to 3 cm of the soil. Each plot consisted of four rows of sugar beet spaced 50 cm apart and 5 m long and density of sugar beet was 12 plants per m2. Seedbed preparation operations consisted of moldboard plowing, double disking and application of N at 69 kg.ha-1, P2O5 at 67.5 kg.ha-1 and K2O at 50 kg.ha-1 was done according to the soil test and the fertilizer recommendations. Irrigation was performed once a week. In order to determination of total weed biomass and density, weeds existing in the area 1×1 m2 were collected, counted and weighted. Also sugar beet root yield and biomass was recorded for same area. Data were subjected to ANOVA using the PROC GLM procedure in SAS Version 9.4 and means were compared using Fisher’s protected LSD test at the 0.05 level of significance. Drawing of figures were done by SigmaPlot Version 12.5. The relationship between sugar beet root yield and weed density and biomass were described with hyperbolic decay 2 parameters model.
    Results And Discussion
    In the experimental plots, we observed ten species of broadleaf weeds among which redroot pigweed (Amaranthus retroflexus L.), common lambsquarter (Chenopodium album L.), black nightshade (Solanum nigrum L.), purslane (Portulaca oleraceae L.), and field bindweed (Convolvulus arvensis L.) have higher relative frequency and density than others. The results showed that the highest sugar beet root yield, as value 110.29 ton ha-1, occurred in split application of chloridazon plus desmedipham with Adigor. Furthermore, the highest sugar yield obtained from the plots with split application of chloridazon plus (desmedipham plus phenmedipham plus ethofumesate) with Adigor at 16.10 ton ha-1. In split application of desmedipham plus phenmedipham plus ethofumesate without adjuvant, the lowest sugar beet root yield and sugar yield were recorded 50.07 and 7.57 ton ha-1, respectively. Full application of chloridazon plus (desmedipham plus phenmedipham plus ethofumesate) with Adigor with %17 sugar content, and split application of desmedipham plus phenmedipham plus ethofumesate Adigor with %11.74 sugar content had the highest and lowest, respectively. Split application of chloridazon plus desmedipham with Citogate and full application of chloridazon plus (desmedipham plus phenmedipham plus ethofumesate) with Citogate indicated completely weed control, and full and split application of desmedipham plus phenmedipham plus ethofumesate with ammonium sulfate had the lowest performance of weed control. The results of the regression analysis showed that the highest yield of sugar beet occurred when total weed density or biomass are zero (104.62 and 101.41 tonha-1 were estimated, respectively). Also, when weeds density and biomass increased to 24 plants m-2 or 479.13 g dry matter m-2, the root yield of sugar beet will be decreased by 50%.
    Conclusion
    The results of this study showed that split application of chloridazon plus desmedipham with Adigor or Citogate, created the highest sugar beet root yield and appropriate weed control among all treatments. In contrast, split application of desmedipham plus phenmedipham plus ethofumesate without any adjuvant had the lowest performance of weeds control. It was concluded that the most important factor among the experiment factors was the type of herbicide or herbicide combination.
    Keywords: Adigor, Ammonium sulfate, Chloridazon, Citogate, Desmedipham
  • H. Zohdi, R. Hosseini, A. Sahragard, A. H. Mohammadi Pages 74-80
    Introduction
    The common pistachio psylla (CPP), Agonoscena pistaciae Burckhardt and Lauterer, 1989 (Hem.: Psylloidea: Rhinocolinae) is an important pest of pistachio trees. The presence of a large population of psyllid causes severe problems such as falling buds and leaves and therefore this pest causes heavy economic damage to farmers. Predators are the largest and the most diverse natural enemies of the CPP. They are offered as biological control agents against pistachio pests, especially CPP, although they are mostly general predators. Oenopia conglobata contaminata (Menteries) is one of the common psylla predators of pistachio orchard that have a significant role in biological control of Agonoscena pistaciae population. Despite the importance of this efficient predator, the limited study has been done on the effect of different hosts on the biological parameters of this lady beetle. In this study, the demographic parameters of this lady beetle by feeding on 4 different prey species, A. pistaciae , Aphis fabae Scopoli (Hem.:Aphididae), Aphis gossypii Glover (Hem.:Aphididae) and eggs of Ephestia kuehniella (Zell.)(Lep.:Pyralidae) were studied in the laboratory conditions (25 ± 2°C, relative humidity of %65 ±5 and photoperiod of 16 hours light and 8 hours of darkness).
    Materials And Methods
    Nymphs of CPP (A.pistaciae) and adults of O. conglobata contaminata beetles were collected on the pistachio leaves from a pistachio orchard. Aphids (A. fabae and A. gossypii) were reared on the bean and the cotton plants planted in a greenhouse. Eggs of E. kuehniella were prepared from insectarium of Kerman Plant protection management and rearing of E. kuehniella was done in the laboratory conditions in Kerman Agricultural and Natural Resoarce Research Center. Before starting the experiment, one generation of O. conglobata contaminata was reared in the laboratory on the different host separately. One hundred eggs of O. conglobata contaminata were used to determine the demographic parameters. After hatching of eggs, larvae was individually transferred to a plastic container (5*10 cm) and kept in a growth chamber. Every day the larvae were fed with the above mentioned host. Their growth and development were monitored daily and also mortality rate was recorded. In the experiments, fourth-instar nymph of the aphids and A. pistaciae were used. The raw data of the developmental time and female daily fecundity of O. conglobata contaminata individuals were analyzed based on the age-stage, two-sex life table using the computer program TWO SEX MS Chart.
    Results And Discussion
    Results showed that the maximum net reproduction rate (R0) and intrinsic rate of increase (rm) in psylla diet was 290.87 , 0.1559, respectively and the minimum of R0 and rm belong to eggs of E. kuehniella diet (61.68 and 0.1103). This result proves that psylla diet is the best food for O. conglobata contaminata and aphids diets were in the next ranks (R0 and rm in A.fabae and A.gossypii diets were 200.48, 0.140; 72.44,0.128, respectively). Results of mean generation time of O. conglobata contaminata that was rearing on different diets showed that there were significant differences among the different diets. Mean generation time of O. conglobata in Psylla, A.fabae, A.gossypii and egg of E. kuehniella diets were 36.31, 37.72, 33.34 and 37.30 days, respectively. Finite rate of increase (λ) of O. conglobata contaminata by feeding A.pistasciae, A.fabae, A.gossypii and E. kuehniella was determined 1.198, 1.150, 1.136 and 1.116, respectively.The results of this study can be compared with the result of Mokhtari and Samih (2014), Rounagh and Samih (2014) and Hassani et al. (2009). Life expectancy of female and male O. conglobata contaminata by feeding A.pistasciae, A.fabae, A.gossypii and E. kuehniella were 80.82,64.16; 81.02,68.76; 80.54,68.88 and 59.75, 62.11 days, respectively. Results also indicated that the psylla and A.fabae diets improved the demographics parameters and the life expectancy of O. conglobata contaminata.
    Conclusions
    The results illustrated that this predator by feeding on nymphs of A. pistaciae has the highest intrinsic rate of increase (rm) and with respect to the demographic parameters, it was the most suitable prey .The compare of O. conglobata contaminata -rm that rearing by CPP with A. pistaciae -rm proves that this predator can control of A. pistaciae in the field and this ladybeetle can be used in IPM of pistachio orchards. According to the difficulty of rearing CPP in laboratory conditions, aphids are suitable preys for mass rearing of O. conglobata contaminata in insectariums.
    Keywords: Agonoscena pistaciae, Aphis fabae, Aphis gossypii, Demographic parameters, lady beetle
  • R. Mohmad Alinejadi, Seeyed Gholamreza Moosavi Pages 81-91
    Introduction Weed control is an essential part of all crop production systems. Weeds reduce yields by competing with crops for water, nutrients, and sunlight. Weeds also directly reduce profits by hindering harvest operations, lowering crop quality, and producing chemicals which are harmful to crop plants. Results of researches have shown that good weed control within the first four to six weeks after crops are planted is critical in order to avoid a yield reduction by weeds. There are many cultural, mechanical, and chemical methods of weed control which are extremely effective if applied at the correct time. Fields that are kept free of weeds for the first four to six weeks after planting give the crop a "head start" which enables it to shade out or otherwise out compete weeds that emerge later in the season.
    Materials and Methods In order to study the effect of weeds interference on morphological traits, yield and yield components of three safflower cultivars, as well as weed species density and dry weight , a factorial experiment based on a randomized complete block design with three replications was conducted in factorial at the Agricultural and Natural Resources Center of South Khorasan province during 2012 growing season. Experimental treatments consisted of three safflower cultivars (Goldasht, Padideh and Golsefid) and six weed interferences (control or without weeds throughout the growing season, interference until stem elongation, branching, flowering, end of grain filling period and the end of growing season).. Measuring traits included the number of branches, head diameter, number of head per square meter, number of seed per head, seed weight, seed yield, biomass, oil percentage, and oil yield of safflower. Within weed species were identified, counted, clipped at ground level and oven-dried at 72 °C for 48 hours, then weighed to determine their dry matter. All data were subjected to analysis of variance using SAS statistical software and Duncan's multiple range procedure was employed at probability level of 5%.
    Results and Discussion Results showed that all measured traits except head diameter, weeds density and dry weight were significantly differed among cultivars. Number of head per square meter, seed and biological yield, oil percentage and oil yield in the Padideh cultivar was higher than two other cultivars whilst its seed yield had no significant difference with Golsefid cultivar. Interference treatments showed a significant effect on head diameter, number of seed per head, seed and biological yield, oil yield, weeds density and dry weight . Safflower seed yield decreased considerably by extending of weeds interference duration so that interference until flowering, end of grain filling period and the end of growing season were obtained 19.3%, 28.3% and 51.4% compared to control (296.37 g m-2), respectively. Also, weed interference until the end of growing season of safflower reduced oil yield in comparison to control by 35.6%. Simple correlation analysis, revealed seed yield was positively correlated with all the traits except seed weight and oil percentage. The highest weed density (98.7 plants per m2) was observed in interference until stem elongation. Also, increasing of interference duration caused decreased weed density per unit area., So that, weeds dry weight per unit area was increased until the end of grain filling stage, despite the decline in weed density. The results of our study demonstrated that extending of weed interference duration until the end of growing season led to reducing of safflower cultivars yield. Also, Padideh cultivar had the highest oil percentage and oil yield, 25.7%and 70.5 g m-2, respectively.
    Conclusions The study of weed populations and their dry weight per unit area showed that weed dry weight has increased with increasing of weed interference period, in spite of decreasing of their density. The results revealed that the presence of weeds throughout the growing season reduces the yield of safflower cultivars while the level of decline was different in cultivars. Therefore, yield of Padideh cultivar in the presence and absence of weeds was more than two other cultivars. The highest seed yield was recorded from weed control treatments of early growth. In general, weed control in safflower should be done in branching or stem elongation stage.
    Keywords: oil percentage, competition, Branching, head, dry weight
  • R. Amini, H. Abdi, A. Dabbagh Mohammadi Nassab Pages 92-104
    Introduction
    Corn (Zea mays L.) is cultivated widely throughout the world and has the highest production among the cerealsafter rice and wheat. In Iran the total production of corn in 2013 was more than 2540000 tons. Weeds are one of the greatest limiting factors to decrease corn yield in Iran as the average yield loss due to weeds in the fields of Kermanshah in 2009 was 17.32 %. The herbicides are the main weed control method in conventional cropping systems but their application has been increased herbicide resistant weeds and environmental pollution. Integrated weed management combines all applicable including chemical and non-chemical methods to reduce the effect of weeds in the cropping systems. Thus, Weed control strategies such as tillage, mulch, cover crops and intercropping could be used for integrated weed management of corn. Previous studies showed that crop residues such as rye (Secale sereal L.), wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and clover (Trifolium sp.), cover crops and living mulch could inhibit weed germination and growth. Therefore the objective of this study was evaluating the effects of some integrated weed management treatments on weed characteristics, yield components and grain yield of corn.
    Materials And Methods
    In order to evaluate the effect of some weed management treatments on corn (Zea mays L.) yield an experiment was conducted in 2014 in Ravansar, Kermanshah, Iran. This study was arranged based on randomized complete block design with 10 treatments and three replications. The weed management treatments were including 1-chemical control followed by mechanical control (application of nicosulfuron at a dose of 80 g.a.i.ha-1 cultivator 40 days after emergence) 2- chemical control followed by mechanical control (application of 2,4-D〣 at a dose of 675 g.a.i.ha-1 cultivator 40 days after emergence) 3- cultural control followed by mechanical control (planting hairy vetch (Vicia villosa) in the fall 狩涊 40 days after emergence)4- mechanical control (cultivator 25 and 40 days after emergence) 5- cultural control (intercropping of corn with chickpea (Cicer arietinum L.) at density of 200000 plants.ha-1 6- cultural control followed by other cultural control (planting hairy vetch in the fall 詻庭쫨Ꚙ of corn with chickpea) 7- chemical control followed by cultural control (application of glyphosate at a dose of 2050 g.a.i.ha-1 before planting詻庭쫨Ꚙ of corn with chickpea) 8- cultural control (straw mulch application in the fall in amount of 2625 kg.ha-1) 9- cultural control (straw mulch application in the spring in amount of 2625 kg.ha-1) 10- hand weeding during whole season. Also the weed infested treatment was used as control. Sixty days after corn emergence, the weed sampling was done with 1×0.5 (0.5 m2) quadrate in each plot and weed density was recorded. The samples were dried in 75 ºC oven for 48 hours thenweed dry matter was measured. The plant height and leaf number per plant were measured in all plots. Corn was harvested at economic maturity and grain yield and yield components of corn and weed biomass were measured. The analysis of variance of data was performed using SPSS v.16 and Duncan's multiple range procedure was employed at probability level of 5%.
    Results And Discussion
    Results indicated that different weed management treatments had significant effect on weed density and dry matter, corn plant height, leaf number per plant, number of kernel rows per ear, number of kernels per row, number of kernels per ear and corn grain yield (p≤ 0.01). The lowest weed dry matter were obtained in 2, 4-D MCPA cultivator treatment (72 g.m-2) and the highest one observed in intercropping with chickpea (440 g.m-2) and mulch application in the fall (441 g.m-2). The highest value of plant height, number of kernel rows per ear, number of kernels per row and number of kernels per ear were observed in 2,4-D MCPA cultivator, nicosulfuron cultivator and hairy vetch cultivator treatments. The highest corn grain yield was obtained in 2, 4-D MCPA cultivator (8.37 ton.ha-1), nicosulfuron cultivator (6.5 ton.ha-1) and hairy vetch cultivator (6.3 ton.ha-1) treatments, respectively. Also, the lowest grain yield was obtained in mulch application in the fall (1.95 ton.ha-1), intercropping with chickpea (1.96 ton.ha-1) and hairy vetch intercropping with chickpea (2.1 ton.ha-1) that were not significantly different with weed infested treatment. Generally we can conclude that application of cultivator with herbicides had the highest efficacy in weed management of corn.
    Conclusion
    Among the weed management treatments application of 2,4-D MCPA cultivator, nicosulfuron cultivator and hairy vetch cultivator treatments had the most efficiency in corn weed management. This result indicates the importance of cultivator in corn weed management and also it should be used 40 days after corn emergence for high efficacy in weed control. The treatments of intercropping with chickpea and straw mulch had no enough efficacy in corn weed management and should be integrated with other methods. Using non-chemical methods in corn weed management may be causes yield loss but reduces application of herbicides and environmental pollution that is consistent with sustainable agriculture.
    Keywords: Intercropping Cultivator, Hairy vetch, Mulch, Nicosulfuron
  • Sh. Mehdi Karami, Z. Badehian, A. Ahmadi, F. Jafari Asl Pages 105-116
    Introduction
    There are seven species and sub-species of Acer sp. in the Northern forest of Iran. One of the most important diseases of this tree in all over the world is tar spot. Two species of fungi, which cause this disease, are Rhytisma acerinum and R. punctatum from the category of Ascomycetidae. Studies on the Acer platinum sp. show that causative agent of this disease is R.punctatum which cause the early fall and make leaves turning yellow especially in the plant nurseries and forested areas. Therefore, investigating the use of antibiotics in treating this disease in the forest areas is necessary. The objective of the current research was to use Oxytetracycline, Amikacin and Erythromycin in Controlling mycelial growth and spore germination of R. acerinum as Pathogen in tar spot disease at Acer velutinum Boiss in vitro.
    Materials And Methods
    To control the disease of Maple tar spot in the condition of light and darkness, the medium containing oxytetracycline, Amikacin and Erythromycin were used. Four different dosage of 50, 100, 200, 500 microliter, of oxytetracycline 10% in the light and dark conditions in 100cc of distilled water and Amikacin 5% in four different dose of, 100, 200, 400 and 1000 microliter, light and dark conditions in 100 cc of distilled water and for erythromycin 5% four different dose of, 100, 200, 400 and 1000 microliter in 100 cc of distilled water in light and dark conditions each in three repetitions of medium were prepared. In this step, to evaluate the effect of light on the rate of the growth of mycelium and fungal colonies of R. acerinum, for each of the treatments with the different dosage, half of the repetitions were under the light condition and another half in dark condition (incubator). Then, after the growth, radiant growth was measured over one week. To investigate the fungi spore germination, above steps, were performed, as well.
    Results And Discussion
    The results showed that among the mentioned antibiotics with different dosages, oxytetracycline with the dosage of 200 micro liter had the minimum effect on the coefficient of AUFGC. The results clarify that the effect of light and light-material on the coefficient of AUFGC and growth were not significant but the effect of the material on the coefficient of AUFGC and growth had a significant difference. Moreover, the results showed that growth of fungal and mycelia threads at the treatment of oxytetracycline with the dosage of 200 microliters in the medium were destructed and other dosages of this antibiotic (50, 100 and 500 microliters) were not effective in controlling the disease. According to the results, oxytetracycline 200 under light condition and dark condition had the maximum effect in preventing the mycelia growth of the fungi and the treatment of oxytetracycline with the dosages of 50, 100 and 500 microliters and erythromycin with the dosages of 100 and 200 microliters in dark condition had the least effect on the prevention of the mycelial growth of the fungi. Overall, the mycelial growth of the pitch stain disease, in addition to the witness treatment, in the mediums containing the antibiotics with the dosages of 50, 100 and 500 microliters had the most growth. Light or dark had not significant effect on the mycelia growth of the fungi or on the prevention of fungi growth but in controlling the germination of the spores, the treatments of light, material, and light-material showed a significant difference. In controlling the germination of the spores in addition to the oxytetracycline with the dosage of 200 microliters, other antibiotics also were effective at the same level regarding the compare means. Moreover, light or dark condition was effective in germination of the fungi spores so that in light condition, the spores of R. acerinum had more germination.
    Conclusion
    Regarding the acquired results, it can be concluded that using antibiotics in controlling the disease of Maple tar spot can be effective and oxytetracycline with the dosage of too in 200 cc distilled water had the maximum effect on controlling R. acerinum. Although, using the antibiotics is effective in controlling the fungi, no need to say that other pre-treatments such as conservation of the trees and keeping the hygienic environment for these trees also is recommended for controlling of these diseases. However, the result of this study can be useful for the management of the forests and related organizations.
    Keywords: Pathogenic fungi, Tar spot, AUFGS coefficient, forest management
  • M. Babaei, S. Saeedipour Pages 117-123
    Introduction Interference weed with crop is a major concern for production in croplands particularly where modern agricultural practices such as mechanical weeding and the application of herbicides are limited. At present, the aim of weed management is to keep weed population at an acceptable level rather than to keep crop totally free of weeds. Among the weed control methods, the chemical control is the easiest one of the recent origins, as well the most successful alternative method.
    Materials and methods Field experiments were conducted at Shoushtar Branch, Islamic Azad University, Iran (32 0 3´ N, 480 50´ E) during winters of 2012-2013 in order to evaluate the effect of sulfosulfuron and sulfosulfuron plus metsulfuron-methyl at 30 and 45 g a.i. ha-1, respectively, and wheat seed rate at 180, 200 and 220 kg ha-1 on weed control. Experiments were carry out in a randomized complete block design with a factorial arrangement and four replicates. The plot size was 6 m × 2 m. The soil was a clay loam texture, pH 7.4 and 0.6 % organic matter content. In the experimental site, the 30-year average annual rainfall is 321.4 mm, daily average annual air temperature is minimum and maximum 9.5 °C and 46.3 °C, respectively. Wheat cv. Chamran was planted in the first fortnight of November. Seedbed preparation consisted of moldboard plowing, disking and leveling. A basal fertilizer rate of 125 kg ha-1 N (form of urea (46% N)), 75 kg ha-1 P2O5 (diammonium phosphate (18% N; 46% P2O5)), and 60 kg K2O ha-1 (sulfate of potash (50% K2O)) was applied. The whole P and K and half of N were applied at sowing. The remaining half of N was top dressed with the irrigation at the booting stage.
    Results and Discussion As the crop population brings competition for limited resources with the weeds, we tested different seeding rates to increase crop plant density as a measure to control weeds. The weed population was significantly affected by seed rate. In general, there was an inverse relationship between weed density (p
    Keywords: Crop weed competition, Grain yield, Seed rate, Weed dry weight
  • N. Heidarzadeh, E. Mahdikhani Moghadam, M. Pachenary Pages 124-130
    Introduction
    Nematodes (Phylum Nematoda) are considered as one of the most abundant and diverse animals on earth. They are found in terrestrial, freshwater, brackish, and marine environments and play important ecological roles in soil ecosystems. The order Tylenchida includes the largest and economically most important group of plant-parasitic nematodes so they have always received ample taxonomic attention. Many plant parasitic nematode species are important pests of fruit trees. They damage the plant by directly attacking roots and subsequently predisposing them to secondary infections by bacteria, fungi by causing replant and pre-plant problems of orchards and also by transmission of viruses. Plant parasitic nematodes feed on a plant root system, ability to take up water and minerals and to transport nutrients to the shoot. This restricts root growth reduce plant vitality and inhibits shoot growth, the combination of which results in decreased in quality and yield. The economically most important species belong to the genera Meloidogyne, Pratylenchus, criconemella, Logidorus, Xiphinema, Trichodorus and Paratrichodorus and are widely distributed in fruit orchards throughout the world. Nematode species are classically defined on the basis of these qualitative and quantitative characters. Although morphological information might help species diagnostics, these characters are homoplasious features in many cases and do not adequately consider the possibility of convergent evolution. As a result, new species descriptions are increasingly supported by molecular evidence. However, the study of morphology remains a critical necessity as morphology is the primary interface of an organism with its environment with key implications for development and ecology. Therefore, a more robust phylogeny based on a combination of morphological and molecular approaches is needed to clarify important relationships within Tylenchomorpha. The purpose of the present investigation was the identification of plant-parasitic nematodes of fruit trees based on morphological and morphometrical characters in Northern Khorasan province.
    Materials And Methods
    In order to investigate the biodiversity of plant parasitic nematodes of fruit cultivation in Northern Khorasan Province, 70 soil samples were collected during 2011-2012. Nematodes were extracted by centrifugal flotation technique and transferred to glycerin according to the modified De Grisse method (1969). The permanent slides were prepared from the extracted nematodes. The nematodes were identified by light microscopy, based on morphological and morphometrical characters. Measurements and drawings were performed using a drawing tube attached to an Olympus BH2 light microscope. The ratios and the morphometric symbols used in morphometric tables of each specimen. Nematodes were identified based on morphological and morphometrical characters using identification keys.
    Results And Discussion
    In this study, 17 species from 13 genera belonged to sub order Tylenchina were identified as follows: Aphelenchoides richardsoni, Aphelenchus avenae, Basiria graminophila, Boleodorus thylactus, Ditylenchus filimus, D. medicaginis, Filenchus cylindricaudatus, F. thornei, Geocenamus tenuidens, Helicotylenchus digonicus, H. pseudorobustus, Heterodera schachtii, Merlinius brevidens, Pratylenchus neglectus, P. thornei, Tylenchorhynchus latus, Zygotylenchus guevarai.
    Among these species, Pratylenchus neglectus, Merlinius brevidens and Boleodorus thylactus were more frequent, respectively. Ditylenchus filimus is reported for the first time from Iran. D. filimus is characterized by low and striated head, stylet 7-9 µm, median bulb muscular, glandular bulb offset, posterior vulva( V=81-85), PUS=0.5-1.1, tail conical with very sharp and pointed terminus.
    Conclusion
    In this study, 17 species from 13 genera belong to suborder Tylenchina were identified. Among these species, Pratylenchus neglectus, Merlinius brevidens and Boleodorus thylactus had the most frequency respectively. Ditylenchus filimus is reported for the first time from Iran.
    Keywords: Fruit trees, Northern Khorasan Province, Plant parasitic nematode
  • M. Shahiri Tabarestani, K. Rahnama, M. Jahanshahib, S. Nasrollanejada, M. H. Fatemi Pages 131-141
    Introduction
    Fungi release wide spectrum of secondary metabolites that belong to several chemical groups with different biochemical origins. These materials produce as intermediate and end products of diverse metabolic pathways. The profile of the secondary metabolites for a known species or strain will vary depending on the substrate, the duration of incubation, the type of nutrients, temperature and other environmental parameters. Trichoderma spp. are well-known producers of secondary metabolites with different biological activities. The secondary metabolites with antibiotic activity can be classified into two main types. Low molecular weight and volatile metabolites which are involved in complex Trichoderma plant-pathogen interactions. They belong to various structure classes such as alcohols, ketones, alkanes, furans, simple aromatic compounds, isocyanate compounds, volatile terpenes, some polyketides, butenolides, and pyrones. All of them are relatively nonpolar compounds with a significant vapor pressure. These volatile organic compounds (VOCs) in the soil environment could be traveled over distance and affect the physiology of the pathogens. They also enhance growth and systemic resistance in plants. These VOCs have been evaluated for T. atroviride, T. harzianum, T. viride, T. longibrachiatum, T. pseudokoningii and T. aureoviride. High molecular weight metabolites (like peptaibols) are polar metabolites which act directly by contact between Trichoderma species and competitor organisms. Due to potent separation and highly sensitive detection, gas chromatography-mass spectrometry (GC-MS) is the main method for detection of the fungal VOCs. Mass spectrometric detection offers the possibility to identify individual volatiles from complex mixtures. Structure characterization and confirmation of identity are usually achieved by comparison of mass spectra with library spectra and the determination of chromatographic retention indices. Due to the capacity of Trichoderma species in crop protection and promoting vegetative growth, they are marketed as biopesticides, biofungicides and biofertilizers. The identification of molecules with such biological activities can support the development of new biopesticides and biofertilizers based on Trichoderma metabolites. The aim of this study was to investigate antifungal effects and chemical composition of secondary metabolites produced by Trichoderma atroviridae(6022) against Macrophomina phaseolina and Sclerotinia sclerotiorum.
    Materials And Methods
    Antifungal effects of isolate 6022 against M. phaseolina and S. sclerotiorum were evaluated under invitro condition by dual culture technique, volatile (Dennis & Webster 1971) and non-volatile (Vinal 2006) metabolites. Volatile metabolites tests were done in 4 cases: Co-culture, 24, 48 and 72 hour cultures. For considering non-volatile metabolites of this isolate, different concentrations of culture filtrate and mycelial mass have been prepared in (autoclaved) potato dextrose agar (PDA), individually. Secondary metabolites were extracted via 4 processes by using of organic solvents (Siddiquee 2012), Headspace technique (Stoppacher 2010) and soxhlet water bath distillation methods for mycelial mass (Dubey 2011) and identified by using the GC-MS device with nonpolar column (DB-5).
    Results And Discussion
    In dual culture test, isolate 6022 inhibited the mycelial growth of the pathogen, then over ran and sporulated on the mycelia. The related results for the volatile test in 24, 48, 72h and Co-cultures, indicated that the antagonist inhibited the mycelial growth of the pathogen and production of sclerotia in culture media (PDA). Results of the non-volatile test (in different concentrations) showed significant inhibitory effects on mycelial growth and production of sclerotia. After extraction and GC separation, the constituents of mixtures can be detected via mass spectrometry (MS) by comparison of mass spectra with library spectra searching. According to mass spectra library, 61 compounds such as some alkanes, alkenes, phenolic, alcoholic, terpenoid and aromatic compounds have been detected by 4 processes that among them, alkanes had the highest frequency. Many important compounds with the antifungal effect such as iso-amyl-alcohol, 2-ethyl-1-hexanol, 1-pentanol, stearic acid, palmitic acid, bis (2-ethylhexyl) phthalate, di-n-octyl phthalate have been identified. So, inhibitory effects of isolate 6022 are related to these compounds.
    Conclusions
    Secondary metabolites of the biocontrol fungus Trichoderma have been involved in different biological processes such as biocontrol or communication between fungi and their living environment. These fungi have antibiotic activity against plant pathogenic fungi, so the requirement for monitoring Trichoderma VOCs profiles has been offered. The results showed that isolate 6022 has the potential for controlling above mentioned pathogens so it can be the suitable alternative for chemical toxins. This method is simple for extraction of the secondary metabolites, under laboratory conditions and studied in Iran for the first time.
    Keywords: GC-MS, Macrophomina phaseolina, Sclerotinia sclerotiorum
  • Shahla Faramarzi, Roozbeh Farhoudi Pages 142-151
    Introduction Allelopathy means any process involving the secondary metabolites (allelochemicals) produced by plants, algae, bacteria, and fungi (excluding animals) that influences the growth and development of agricultural and biological systems, with positive or negative effects. Plants produce secondary metabolites and in certain circumstances, these can act as phytotoxins, inhibiting or promoting some biochemical or physiological processes in the other plants or organisms. Toxicity of allelochemical compounds include effects on growth, chlorophyll content, photosynthesis, transpiration, stomatal conductance, relative growth rate, and oxygen uptake in many crops. Furthermore, the influence of allelochemicals on alpha amylase, oxidase, sucrose synthase activity and malon dialdehyde concentration were analysed. The role of numerous plant secondary metabolites is still unclear, and this raises curiosity for both plant physiologist and ecologists. Inhibitory effects on germination and establishments of crops caused by residues of either crops or weeds have lead to investigation of the release of toxic compounds from such residues. This present study was designed to evaluate the allelopathic potential of milk thistle for controlling common cocklebur in vegetables.
    Materials and Methods In order to investigate the effect of milk thistle aqueous extract on growth and enzyme activities of common cocklebur seedlings, two separate experiments were carried out in randomized complete design and randomized complete block designs with five and four replications, respectively, in spring 2012 in seed technology laboratory and greenhouse of Azad University, Shoushtar branch, Shoushtar, Iran. Milk thistle aqueous extract concentrations were involved (0, 5, 10 and 15% (v/v)) in petridish and (0, 10, 20 and 30% (v/v)) as spraying on common cocklebur seedlings under greenhouse conditions. Whole plants of milk thistle were gathered from medicine plant farm of Azad University. Then, their flowers were cut and their shoots were dried in 60 °C and grinded. For preparing aqueous extract 100 g powder of milk thistle dissolved in 1000 ml distilled water and maintained at 20 °C. The solution was filtered and cleared. The aqueous extract was considered as stock and other aqueous extracts were prepared from it. After application extract concentration in petridish and pot, seedling fresh weight, activity of sucrose synthase, alpha amylase, catalase enzymes and malon dealdehyde concentration of common cocklebur were measured. Statistical calculations were accomplished through the SPSS software and graphs were drawn by the Excel software.
    Results and Discussion Results showed that fresh weight of common cocklebur seedlings were affected by milk thistle extract. Milk thistle extract reduced alpha amylase enzyme activity and seedling growth of common cocklebur. In addition, increase in aqueous extract of milk thistle resulted in reduction and increase in catalase and malon dialdehyde concentration in cocklebur seedling; respectively. The minimum alpha amylase enzyme activity (2.1 nM/g seed/min) and seedling fresh weight (0.32 g) were observed in 15% aqueous extract. Malon dialdehyde concentration of cocklebur seedlings was 0.4 (nM/g FW) in 15% aqueous extract of milk thistle. Catalase enzyme activity was the lowest (1.4 nM H2O2/mg Protein/min) and the greatest (27 protein absorption/60s) in 15% aqueous extract of milk thistle. In greenhouse experiment, also, with increasing aqueous extract of milk thistle was reduced seedling fresh weight, catalase and sucrose synthase enzyme activities. Catalase and sucrose enzyme activities were 1.8 (nM H2O2/mg Protein/min) and 2 (nM/ mg protein/min) at 30% aqueous extract of milk thistle. Futhermore, increase in aqueous extract of milk thistle resulting in increase cell memberane destruction and malon dialdehyde concentration in cocklebur seedling tissue. The lowest (0.0029 nM/g FW) and greatest (0.93 nM/g FW) malon dialdehyde concentration was at 30% aqueous extract.
    Conclusions In this study, with increasing the amount of milk thistle extract, values of measured traits including fresh weight, sucrose synthase and catalase enzymes of cocklebur seedlings compared to control treatment (distilled water) have a decreasing trend, but malon dialdehyde concentration of cocklebur seedlings had increased compared to the control. The destruction of cell membranes under the influence of cocklebur allelopathic compounds can be one reason for the reduced growth of weed seedlings. Reduced sucrose synthase activity, led to reduced production of sucrose that was associated with reduced seedling growth. The present study confirmed that milk thistle can be used as an allelopathic plant for weed suppression in agroecosystems through its release of allelochemicals. Knowledge about the challenges related to the demonstration of allelopathy, as an ecological significant mechanism, is important in the assessment of ecological effects of allelopathic plants.
    Keywords: Antioxidant, Alpha amylase, Catalase, Malon dialdehyde, Sucrose synthase
  • A. Khatami, M.T. Alebrahim, M. Mohebodini, R. Majd Pages 152-165
    Introduction Potato is globally the fourth important food crop after rice, wheat, and maize and is cultivated in several countries worldwide like Iran. Weeds are the most important restriction factor for crop development in agricultural systems and the absence of weed control lead to crop yield reduction between 10 to 100 percent and this reduction could be a serious threat for a growing world population to be considered. Rimsulfuron is a sulfonylurea herbicide for control of weeds in potato, corn, wheat, barley and canola. It can be used as pre or post emergence in potato. These herbicide act through inhibition of enzyme acetolactate synthase (ALS), which catalyzes key reactions in the biosynthesis of basic branched-chain amino acids that are essential components of the growth process in plant cell division such as valine, leucine, and isoleucine
    Materials and methods In order to study rimsulfuron (Titus 25% DF) effect on weed biomass as a postemergence herbicide, a field experiment was carried out in the farm located 3 km out the city of Ardabil during 2014. The factorial experiment was performed based on randomized complete block design with three replications. Potato cultivar was Agria (common cultivar in Ardabil). The first factor was rimsulfuron doses with six levels (5, 10, 20, 30, 40 and 50 gr a.i. / ha), and the second factor was time of application based on different potato growth stages, (Potato emergence, stoloning and tuber bulking). Also two treatment (with and without weeding) were considered as control. Tubers were hand sown on 22th May in rows 75 cm apart and 20 cm in the rows at 10 cm depth. Rimsulfuron was applied by backpack sprayer fitted with 8001 flat fan nozzles. Three weeks after treatment, weed sampling was carried out by a quadrate sized 0.375 m2. Tubers were harvested from two center rows to determine total tuber yield per hectare. Two models fitted to the data were three parameter logistic and three parameter sigmoid.
    Data were analyzed using SAS 9.1 and MSTAT-C. Analysis of variance was used to test the significance of variance sources, and Duncan’s Multiple range test (P ≤ 0.05) was used to compare the differences among treatments.
    Results and Discussion Results showed that the maximum reduction percent of redroot pigweed (Amaranthus retroflexus L.), field bind weed (Convolvulus arvensis L.), lambsquarter (Chenopodium album L.), total weed biomass and density achieved by 40 and 50 gr a.i. / ha application. So that 40 and 50 gr a.i. /ha of rimsulfuron compared to control reduced weed density up to 49.47and 55.38 % and biomass up to 89.97 and 94.63 %, respectively. Also results showed that 40 and 50 gr a.i. /ha of rimsulfuron compared to control reduced biomass of redroot pigweed 89.91 and 95.50 %, Field bind weed 84.28 and 94.79 % and lambsquarter 92.75 and 96.87 percent respectively. That there was not statistically significant difference between 40 and 50 gr a.i. /ha of rimsulfuron.
    Among rimsulfuron application times, potato emergence stage reduced total weed density and biomass 36.45 and 68.04 %, respectively which is compared to control (weedy). Rimsulfuron application at potato emergence stage reduced biomass of redroot pigweed and lambsquarter 62.51 and 71.08 percent respectively. However it had no significant effect on biomass of Field bind weed.
    The results showed that potato tuber yield was 46.31 and 45.96 ton/ ha while rimsulfuron applied 40 and 50 gr a.i. / ha. Among rimsulfuron application times, potato emergence stage had total tuber yield 47.58 ton/ha.
    Conclusion Results showed that the maximum reduction percentage in weed density and biomass was observed for treatments in which were used 40 and 50 gr a.i. / ha application. Application of rimsulfuron at potato emergence reduced weed density and biomass and increased total tuber yield. Itproves the effectiveness of the rimsulfuron for potato emergence without damage. Furthermore the effective dose of rimsulfuron for 50 percent reduction in biomass of redroot pigweed, field bind weed and lambsquarter were 14.36, 12.26 and 10.17 g a.i. /ha, respectively. The results also showed that rimsulfuron application 40 and 50 gr a.i. /ha increased total tuber yield by 19.90 and 20.51% respectively. Application of 40 and 50 gr a.i. / ha at potato emergence stage produced maximum total tuber yield per hectare. The result of this study showed that 40 and 50 gr a.i. /ha rimsulfuron application at potato emergence assessed as the best treatment to control weed and increase total yield.
    Keywords: Broad leaf weeds, Dose response, Tuber yield, Weed biomass, Weed density
  • N. Amanifar Pages 166-171
    Introduction
    Polystigma amygdalinum Sacc (Cannon sp nov.) causes almond leaf blotch and is reported from various countries. The pathogen is widely distributed in the Mediterranean region and often causes premature defoliation of its host. Based on morphology, P. amygdalinum has been assumed to be a member of the order Phyllachorales and is consid¬ered to be a close relative of the genus Phyllachora, but phylogenetic analyses indicated that P. amygdalinum did not group with Phyllachora species (Phyllachorales) which have been thought to be its close relative. Polystigma amygdalinum show to be a relative of Trichosphaeriales and Xylariales and placed in the Xylariomycetidae. Almond leaf blotch is the most important disease on the leaf in almond (Prunus dulcis) in Iran. Ascospores are believed to be the only inoculum of this pathogen. Ascocarp initials develop in infected leaves in contact with, or in close proximity to, filamentous spore-bearing bodies, which are the first to appear. Environmental factors were affected ascocarp formation and development in P. amygdalinum. Mature ascocarps were formed in leaves from July to October (leaf fall). Ascocarps were produced under field conditions in infected leaves buried in soil at the depths of 0 to 40 cm with maximum mature ascocarp formation at 5 cm and minimum at the soil surface. Based on the appearance of disease symptoms under natural and greenhouse conditions the incubation period was estimated about to be 40-45 and 35-40 days respectively. The peak of ascospore discharge was 2-3 weeks after petal fall and was dependent on rain fall. Various chemicals were applied to control P. amygdalinum on almond. Spraying with Mancozeb and Bordeaux mixture is the most effective with four applications after petal fall in East Azerbaijan. Over a 4-year study period, it was found that ascospore discharge began at flowering and continued for 4-5 weeks in Maharloo of Fars Province. The maximum discharge occurred at petal fall. The incubation period was estimated to be 4-5 weeks under experimental conditions. Although the mature ascospores could produce short germ tubes in distilled water or water agar, the fungus could not be cultured or grown on conventional media from either ascospores, pycnidiospores or stromatic tissues under laboratory conditions. Of several systemic and non-systemic fungicides evaluated under field conditions, triforine at 100-400 µg /ml was most effective. Other fungicides which significantly reduced leaf infection were, in order of efficacy, copper oxychloride (2000µg/ml), copper hydroxide (2000 µg/ml), Bordeaux mixture (10000 µg/ml) and mancozeb (2000 µg/ml). Carbendazim and thiophanate methyl (500 µg/ml) increased the level of infection. One application of the fungicide at petal fall and then at two at 14-day intervals were found to be effective in reducing the disease. Two applications of Bordeaux mixture at 2 and 4 weeks after petal fall was found to be the most efficient control treatment in Chahar Mahal and Bakhtiari. A single spray two weeks after petal fall also reduced the disease significantly.
    Materials And Methods
    During 2012-13, the efficiency triforin (Saprol® 30%) (500 µg /ml) with three timing of applications, in comparison with Bordeaux mixture (10000 µg /ml) on two local cultivars (Sefid and Mamaee), was tested in a completely randomized block design, in along Zayanderood of Chahar Mahal and Bakhtiari province.
    Results And Discussion
    According to the results, two applications of triforin at two and four weeks after petal fall, a single spray four weeks after petal fall and two applications of Bordeaux mixture were found to be the most efficient control treatment in both cultivars, respectively. All applications of fungicides on both cultivars reduced the disease significantly. Infectivity percent and disease severity on Mamaee cultivar were more than Sefid. In general, it can be said Triforin was more effective in terms of decreasing infectivity percent and disease severity in comparison with Bordeaux mixture.
    Conclusion
    The results of this study, previous researches and surveys in Chahar Mahal and Bakhtiari province and other parts of Iran show that some of the almond cultivars cultivated in the country are susceptible to P. amygdalinum, so the only method to manage this disease is using the chemical control on these cultivars. Two applications of fungicides at two and four weeks after petal fall was found to be the most efficient control treatment in Chahar Mahal and Bakhtiari, these results are recommended for all regions of Iran.
    Keywords: Almond red leaf blotch, timing application
  • S. Goudarzvande Chegini, H. Abbasipour, J. Karimi, A. Askarianzadeh Pages 172-178
    Introduction
    The tomato leafminer (TLM), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is an important pest on tomato, potato and other Solanaceous with a great economic importance. Tomato borer can be regarded as a serious threat to tomato production in Iran. TLM larvae cause losses of up to 100% by attacking tomato leaves, flowers, stems, and especially fruits. TLM larvae act as leaf miners, and in high numbers, they can totally destroy the plant foliage; TLM infestation can destroy crop production early on by infesting both developing and ripe fruits. Management of the pest can be problematic, particularly when the infestation pressure is high. One of the main tools in its management is the use of conventional synthetic insecticides, however, this overreliance on the use of synthetic insecticides quickly leads to problems of insecticide resistance. The use of natural compounds such as plant essential oils is considered as alternatives to chemical pesticides due to their lower toxicity on the non-target and low persistence in the environment. In recent years essential oils of medicinal plants have received much attention as pest control chemical agents. The discovery of active compounds that are less persistent will be beneficial for both the environment and agricultural product consumers.
    Materials And Methods
    The egg, 2nd larval instars, and adult of TLM were used to determine the fumigant toxicity of the C. cavi. The essential oil of aerial parts of C. cavi, was extracted by hydrodistillation using a modified Clevenger-type apparatus. Conditions of extraction were: 50g of air-dried sample, 1:12 plant material/water volume ratio and 4h distillation. The obtained oil was dried over anhydrous sodium sulfate and stored in the refrigerator at 4°C until used. The fumigant toxicity of essential oil on larvae 2nd (inside leaf) and egg were tested in macro plastic container volume 1800 ml, The vials were contained leaves containing larvae mines with ten larvae (2nd instars) or 20 eggs, separately. Fore 2nd larvae (outside leaf) and adults bioassay experiments in glass vial volume 600 ml that contained ten larvae (2nd instars) or 10 adults, separately. No. 1 Whatman filter paper disks attached to the undersurface of vials. Filter papers were impregnated with series of pure concentrations of essential oil ranging from 20-100 µl L-1 air, 3-7 µl L-1 air, 0.1-1 µl L-1 air and 0.5-1 µl L-1 air were used in the main bioassay tests for the egg, 2nd larval instars (inside leaf and outside leaf) and eggs, respectively and each concentration and control included three replicates. The mortality was recorded for 2nd larvae and adults after 48 hours. Experiments were carried out at 27±2°C and 65±5% R.H. The rate of mortality was recorded after 48 hours. The type and amount of constituents of the essential oils were analyzed by GC/MS.
    Results And Discussion
    Results showed that the essential oil of C. cavi had high mortality on the different stage of TLM after 48 hours exposure. There was no mortality in controls. The essential oil showed strong adulticidal, larvicidal and ovicidal activity. The results showed that by increasing oil concentration, the mortality was increased. Based on Probit analysis, the LC50 values for egg, 2nd larvae inside the leaf, 2nd larvae outside leaf and adults were 44.24, 4.652, 0.335 and 0.624 µl L-1 air, respectively. The major constituents of C. carvi was Benzaldehyde, 4- (1- methyl ethyl) – (c) (21.26%)
    Conclusions
    Essential oil extracted from C. carvi proved to be very toxic different stage of TLM. On the basis of these LC50 values, larvae (outside leaf) and adults were much more susceptible than eggs and larvae (inside leaf). It should be noted that C. carvi showed remarkable insecticidal activity without any apparent phytotoxicity for leaves of tomato plants. The results showed that the caraway essential oil has high potential in controlling tomato leaf miner and will have purely to be advised for the safeguarding of the environment and the health of the user. Especially that application of synthetic insecticides arise development of resistance and pollution of the environment. In summary, results indicated that these essential oils have good fumigant toxicity on TLM.
    Keywords: Clevenger, Lethal dose, Medicinal plants