فهرست مطالب

نشریه علوم باغبانی
سال سی و ششم شماره 4 (پیاپی 56، زمستان 1401)

  • تاریخ انتشار: 1401/11/01
  • تعداد عناوین: 15
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  • سیده فاطمه متولیان، بهرام عابدی*، یحیی سلاح ورزی، علی تهرانی فر صفحات 735-745

    از مشکلات عمده تولید انار که تقریبا در تمام مناطق انارکاری دنیا بخصوص در مناطق گرم و خشک شایع است، عارضه ترکیدگی میوه آن می باشد که بعد از کرم گلوگاه انار بیشترین خسارت را به باغ داران وارد می نماید. از سوی دیگر تحقیقات مختلف گویای این واقعیت می باشد که حلقه برداری بر ویژگی های کمی و کیفی میوه درختان مختلف تاثیر دارد؛ بنابراین آزمایشی به منظور بررسی تاثیر زمان حلقه برداری بر ویژگی های کمی، کیفی و همچنین شدت عارضه ترکیدگی دو  رقم ’شیرین پوست قرمز‘ و ’ملس‘ در شهرستان مهدی شهر استان سمنان انجام پذیرفت. حلقه برداری در سه زمان تمام گل، دو ماه پس از تمام گل و چهار ماه پس از تمام گل انجام گرفت. نتایج نشان داد حلقه برداری در زمان تمام گل و دو ماه پس از تمام گل توانست درصد ترکیدگی میوه را در هر دو رقم به طور چشمگیری نسبت به تیمار شاهد (عدم حلقه برداری) کاهش دهد. همچنین در بین دو رقم مورد مطالعه درصد ترکیدگی در رقم ’شیرین پوست قرمز ‘ بیشتر از رقم ’ملس‘ بود. علاوه بر این، حلقه برداری در زمان تمام گل و چهار ماه پس از تمام گل توانست میزان وزن، حجم میوه و میانگین وزن 100 آریل را افزایش دهد. از بین دو رقم مورد مطالعه در پژوهش نیز رقم ’ملس‘ نسبت به رقم ’شیرین پوست قرمز‘ میزان مواد جامد محلول و درصد اسید قابل تیتراسیون بالاتری نشان داد.

    کلیدواژگان: رقم شیرین پوست قرمز، رقم ملس، مواد جامد محلول، وزن میوه
  • بهزاد کاویانی*، مریم جمالی، محمدرضا صفری مطلق، علیرضا اسلامی صفحات 747-761

    گلابی یک درخت چوب سخت است که اغلب از بذر رشد می کند. تکثیر از طریق بذر زمان بر است و احتمال تغییرات ژنتیکی را افزایش می دهد. مناسب ترین روش تکثیر گلابی، استفاده از قلمه ساقه می باشد که سخت ریشه زا است. در این پژوهش از غلظت های 1000، 2000 و 4000 میلی گرم در لیتر ایندول بوتیریک اسید (IBA) و نفتالین استیک اسید (NAA) برای تسهیل ریشه زایی قلمه ساقه گلابی  رقم ’بارتلت‘ استفاده شد. نتایج نشان داد که کمترین زمان (59 روز) تا شروع ریشه زایی قلمه ها و بیشترین تعداد ریشه (16) در قلمه های تیمارشده با 1000 میلی گرم در لیتر NAA همراه با 2000 میلی گرم در لیتر IBA به دست آمد. این تیمار به عنوان بهترین تیمار برای ریشه زایی قلمه ساقه گلابی پیشنهاد می شود. بالاترین درصد ریشه زایی (66/57 درصد) در قلمه های تیمارشده با 4000 میلی گرم در لیتر IBA به دست آمد. بیشترین تعداد برگ (93/9) در قلمه های تیمارشده با 2000 میلی گرم NAA همراه با 4000 میلی گرم IBA مشاهده شد. در این پژوهش؛ حجم ریشه، طول ریشه، ارتفاع قلمه و وزن تر و وزن خشک قلمه ها نیز اندازه گیری شد.

    کلیدواژگان: اکسین، تنظیم کننده های رشد گیاهی، خانواده گل سرخیان، قلمه های خشبی، گیاهان میوه
  • رقیه راعی، وحید اکبرپور*، محمدعلی بهمنیار صفحات 763-776

    مدیریت کود یکی از عوامل اصلی در جهت رسیدن به کشاورزی پایدار محسوب می شود. از این رو نظام کشاورزی تلفیقی استفاده از مواد آلی همراه با مصرف بهینه کودهای شیمیایی را توصیه می کند. مدیریت تلفیقی کود دامی با کود شیمیایی روش مهمی برای افزایش تولید و حفظ باروری خاک می باشد. هدف از پژوهش حاضر بررسی نقش کود آلی پلت مرغی و سولفات روی در پرورش گیاه مرزه می باشد. آزمایش حاضر به صورت فاکتوریل در قالب طرح کاملا تصادفی با 3 تکرار انجام گرفت. فاکتور اول کود مرغی با چهار سطح (صفر، 3، 6، 9 تن در هکتار) و فاکتور دوم سولفات روی با چهار سطح (صفر، 50، 100، 150 میلی گرم در کیلوگرم خاک) بود. با توجه به نتایج به دست آمده، اثر کود آلی مرغی، سولفات روی و برهمکنش آنها بر بیشتر صفات مورد بررسی معنی دار بود. بیشترین ارتفاع بوته در تیمار کود آلی مرغی 9 تن در هکتار + سولفات روی 100 میلی گرم در کیلوگرم خاک مشاهده شد که نسبت به شاهد 26/79 درصد افزایش نشان داد و کمترین ارتفاع بوته متعلق به تیمار شاهد بود. کلروفیل کل در تیمار کود مرغی 6 تن در هکتار + 150 میلی گرم سولفات روی در کیلوگرم، افزایش قابل توجهی نسبت به شاهد داشت. بیشترین میزان نیتروژن برگ در تیمار کود مرغی 9 تن در هکتار + 50 میلی گرم سولفات روی در کیلوگرم با افزایش 03/82 درصدی نسبت به شاهد به دست آمد و عنصر روی با افزایش 75/222 درصدی در تیمار کود مرغی 9 تن در هکتار + 150 میلی گرم سولفات روی در کیلوگرم مشاهده شد. تیمار کود مرغی 6 تن در هکتار + 150 میلی گرم درکیلو گرم با 53/261 درصد افزایش نسبت به شاهد حاوی بیشترین درصد اسانس بود. نتیجه پژوهش حاضر نشان داد استفاده از نسبت های تلفیقی کود آلی مرغی و سولفات روی در بهبود صفات رویشی، عناصر در دسترس گیاه و درصد اسانس موثر واقع شده است.

    کلیدواژگان: اسانس، تغذیه، خصوصیات فیتوشیمیایی، سولفات روی، کود دامی، گیاه دارویی
  • معظمه شهابی، سمیه رستگار* صفحات 777-789

    یکی از عمده ترین مشکلات در مرحله پس از برداشت گل شاخه بریده نرگس رقم ’شهلای شیراز‘ (Narcissus tazetta L.cv. Shahla-e-Shiraz)، کوتاه بودن عمر پس از برداشت آن است که به طور عمده به دلیل پژمردگی و قهوه ای شدن سریع گلبرگ های آن می باشد. مطالعه حاضر به منظور بررسی تاثیر تیمار سدیم نیتروپروساید بر حفظ کیفیت و جلوگیری از فرآیند قهوه ای شدن گلبرگ های گل شاخه بریده نرگس انجام شد. آزمایش حاضر به صورت فاکتوریل در قالب طرح کاملا تصادفی با سه تکرار به صورت فروبری کوتاه مدت در سدیم نیتروپروساید در دو غلظت (25 و 50 میکرومولار) به مدت 24 ساعت برروی گل های شاخه بریده نرگس انجام شد. محلول ساکارز 2 درصد و همچنین آب مقطر به عنوان شاهد در نظر گرفته شدند. در این آزمایش شاخص های مختلف بیوشیمیایی و فیزیولوژیکی مورد بررسی قرار گرفت. بر اساس نتایج به دست آمده، بیشترین کیفیت ظاهری گل (03/3) و بیشترین محتوی نسبی آب گلبرگ (1/43 درصد) در پایان آزمایش در گل های تیمار شده با 25 میکرومولار سدیم نیتروپروساید مشاهده شد. کمترین میزان قهوه ای شدن (3/22 درصد) و تغییرات رنگ (ΔE) و بیشترین روشنایی رنگ گلبرگ ها (L*) (47/35) نیز در تیمار 25 میکرومولار سدیم نیتروپروساید مشاهده شد. تیمار 25 میکرومولار سدیم نیتروپروساید به طور معنی داری فعالیت آنزیم پلی فنل اکسیداز را به یک پنجم نسبت به شاهد کاهش داد. این غلظت همچنین تاثیر معنی داری در کاهش نشت یونی و حفظ پایداری غشای سلولی (3/73 درصد) نسبت به شاهد (5/69 درصد) داشت. نتایج نشان داد که غلظت مناسب سدیم نیتروپروساید با حفظ محتوی نسبی آب گلبرگ، کاهش نشت یونی وحفظ پایداری غشای سلولی و کاهش فعالیت آنزیم پلی فنل اکسیداز (PPO) نقش موثری در مهار فرایند قهوه ای شدن گلبرگ های گل شاخه بریده نرگس داشت.

    کلیدواژگان: پایداری غشاء، پس از برداشت، پلی فنل اکسیداز، فعالیت پراکسیداز، نیتریک اکسید
  • حمیدرضا کریمی*، نعیمه بی نیاز، علی اکبر محمدی میریک، مجید اسمعیلی زاده، زینب حاتمیان صفحات 791-802

    به منظور بررسی اثر پایه و پیوندک بر جذب عناصر غذایی در دو رقم انار’رباب نیریز‘ و ’خفر جهرم‘ پژوهشی به صورت آزمایش فاکتوریل در قالب طرح بلوک های کامل تصافی با دو فاکتور پیوندک در دو سطح (’رباب نیریز‘ و ’خفر جهرم‘) و پایه در چهار سطح (’پوست قرمز علی آقایی‘، ’گرچ داداشی‘ ،’گرچ شهوار‘و بدون پیوند) و با پنج تکرار به اجرا در آمد. نتایج نشان داد که برهمکنش پایه و پیوندک بر جذب عناصر تاثیرگذار است. بیشترین میزان فسفر (89/0 درصد ماده خشک)، پتاسیم (95/0 درصد ماده خشک) و کلسیم (59/2 درصد ماده خشک) برگ به ترتیب در نهال های پیوندی با پیوندک’رباب نیریز‘ روی پایه ’گرچ داداشی‘، پیوندک ’خفر جهرم‘ روی پایه ’گرچ داداشی‘، پیوندک’رباب نیریز‘ روی پایه’گرچ شهوار‘مشاهده شد. همچنین بیشترین میزان آهن (75 میلی گرم بر گرم وزن خشک)، منگنز (65 میلی گرم بر گرم وزن خشک) و مس (25 میلی گرم بر گرم وزن خشک) برگ به ترتیب در نهال های پیوندی با پیوندک ’رباب نیریز‘ روی پایه ’گرچ داداشی‘، پیوندک’خفر جهرم‘روی پایه ’گرچ داداشی‘و در هر دو پیوندک روی پایه’گرچ شهوار‘به دست آمد. بر اساس پژوهش فوق می توان بیان کرد که نوع پایه بر غلظت عناصر معدنی شاخساره انار تاثیرگذار است.

    کلیدواژگان: انار، پیوند، پتاسیم، کلسیم، منیزیم
  • داوود کاظمی، مریم دهستانی اردکانی* صفحات 803-815

    کیفیت نور دریافتی توسط برگ ها بر فتوسنتز گیاه تاثیر می گذارد. در پژوهش حاضر اثر طیف های مختلف نور بر کارایی فتوسنتز گیاه گل سنگ (Hypoestes phyllostachya) مورد بررسی قرار گرفت. در این تحقیق با استفاده از آزمون OJIP که از روش های دقیق محاسبه کارایی فتوسنتز در گیاه می باشد، اثرات طیف نور بر فتوسنتز تجزیه و تحلیل شد. آزمایش در بهار سال 99 در گلخانه تجاری با شش اتاقک رشد مجهز به نور معمولی گلخانه (شاهد)، 100 درصد نور آبی، 15 درصد نور آبی + 85 درصد نور قرمز، 30 درصد نور آبی + 70 درصد نور قرمز، 15 درصد نور آبی + 65 درصد نور قرمز + 20 درصد نور سفید و 30 درصد نور آبی + 50 درصد نور قرمز + 20 درصد نور سفید، روی دانهال های چهار برگی گیاه آپارتمانی گل سنگ در قالب طرح کاملا تصادفی انجام شد. پس از دو ماه قرارگیری گیاهان در زیر نورهای مختلف با دوره نوری 12 ساعت روشنایی و تاریکی با شدت نوری 250 میکرومول بر مترمربع بر ثانیه، پارامترهای بیوفیزیک فتوسنتزی بررسی شد. بیشترین میزان شاخص حداکثر کارایی کوانتومی فتوسیستم II و حداکثر فلورسانس متغیر نسبی (FM/F0) در تیمارهای نوری 15 درصد نور آبی + 65 درصد نور قرمز + 20 درصد نور سفید+ 70 درصد نور قرمز و 15 درصد نور آبی + 65 درصد نور قرمز + 20 درصد نور سفید حاصل شد. میزان جذب نور به ازای هر مرکز واکنش (ABS/RC) در گیاهان تحت تیمار نوری 30 درصد نور آبی + 50 درصد نور قرمز + 20 درصد نور سفید نور سفید و نیز شاهد بیشتر از سایر تیمارها بود. میزان گرفتن الکترون به ازای هر مرکز واکنش (TR0/RC) و انرژی اتلاف شده به ازای هر مرکز واکنش (DI0/RC) در گیاهان تحت تیمار نوری 30 درصد نور آبی + 50 درصد نور قرمز + 20 درصد نور سفید و نیز شاهد افزایش یافت. شاخص عملکرد بر پایه جذب انرژی نورانی در تیمار 30 درصد نور آبی + 70 درصد نور قرمز بالاتر بود به طوری که 25/74 درصد بیشتر از شاهد بود. نتایج پژوهش حاضر نشان داد که تیمارهای نوری ترکیبی مخصوصا 30 درصد نور آبی + 70 درصد نور قرمز بیشترین تاثیر را در افزایش کارایی فتوسنتز و نور آبی و شاهد کمترین تاثیر را داشتند.

    کلیدواژگان: فتوسنتز، فلورسانس کلروفیل برگ، کیفیت نور، طیف نور، نشاء
  • محمد اسماعیل نداف، ابراهیم گنجی مقدم*، غلامرضا ربیعی، عبدالرحمان محمدخانی صفحات 817-827

    این مطالعه، با هدف بررسی تاثیر اندازه و منشاء پیوندک روی ریزپیوندی گیلاس در مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی خراسان رضوی در طی سال های 1396-1394 انجام شد. این پژوهش در قالب آزمایش فاکتوریل بر پایه طرح کاملا تصادفی انجام شد. فاکتور اول: رقم در هفت سطح (’زرد‘، ’سیاه مشهد‘، ’دوم رس‘، ’بینگ‘، ’پیش رس‘، ’تکدانه ‘ و ’حاج یوسفی‘) و فاکتور دوم: نوع پیوندک در چهار سطح (ریزپیوندک با اندازه های دو و پنج میلی متری با منشاء درون شیشه ای و برون شیشه ای) بود. عملیات ریزپیوندی با ریزپیوندک هایی از نوک شاخه ارقام گیلاس روی پایه های ’گیزلا 6 ‘ به روش اسکنه انجام شد. گیاهان ریزپیوندی شده، ابتدا برروی محیط کشت MS حاوی یک میلیگرم برلیتر بنزیل آمینو پورین (BAP) و بعد از سه هفته، در محیط پرلیت با محلول غذاییMS  حاوی یک میلی گرم بر لیتر ایندول بوتیریک اسید (IBA) قرار گرفتند و سپس به بستر پرلیت:پیت موس (به نسبت یک :یک) منتقل شدند. نتایج نشان داد که در همه شاخص ها بین تیمارهای نوع پیوندک و اثرات متقابل رقم در نوع پیوندک، به جز زمان گیرایی پیوند، اختلاف معنی دار بود، اما تفاوت معنی داری بین ارقام (به جز رشد طولی پیوندک) وجود نداشت. در نوع پیوندک، ریزپیوندک های پنج میلی متری با منشاء درون شیشه ای دارای بیشترین درصد موفقیت پیوند (42 درصد)، تعداد برگ (7/3)، رشد طولی (3/6 سانتی متر) و زمان گیرایی پیوند (دو روز) بودند و در نهایت در بین تمام ریزپیوندهای موفق، درصد ریشه زایی، 41 درصد و درصد سازگاری، 3/25 درصد بدست آمد. در مجموع استفاده از ریز پیوندک های 5 میلی متری درون شیشه ای در همه ارقام گیلاس، برای ریزپیوندی روی پایه ’گیزلا‘ کارایی بهتری داشت.

    کلیدواژگان: آغازه ی برگی، سازگاری، عاری از ویروس، کشت بافت، نوک شاخه
  • زینب طوسی، سید جواد موسوی زاده*، کامبیز مشایخی، مهدی علیزاده صفحات 829-842

    جنین زایی رویشی، روش جدیدی برای ازدیاد گیاهان در شرایط درون شیشه ای است. کارآیی روش جنین زایی رویشی به شدت به ترکیبات محیط کشت بستگی دارد. مانند ساکارز که متداول ترین منبع کربوهیدرات است که درکشت بافت گیاهی استفاده می شود .ساکارز محصول نهایی فتوسنتز و قند اولیه منتقل شده در آوند آبکش اکثر گیاهان است. به منظور بررسی تاثیر غلظت های مختلف ساکارز بر جنین زایی رویشی مارچوبه (Asparagus officinalis L.) اکتاپلویید، آزمایشی با پنج تیمار ساکارز (3، 6، 9، 12 و 15 درصد) انجام پذیرفت. برای انجام این آزمایش ریزنمونه های مارچوبه حاوی یک جوانه در محیط B5 در فاز القایی جنین رویشی دارای هورمون 2, 4-D کشت شدند و بعد از دو هفته به فاز ظهور جنین منتقل گردیدند. در ادامه بعد از چهار هفته در مرحله ظهور جنین ها، تعداد جنین های رویشی تولیدشده در مراحل کروی شکل و قطبی در دو بزرگنمایی 20 و 40 میکرون، شمارش و عکس برداری شد و میزان تاثیر غلظت های ساکارز بر میزان رنگیزه های فتوسنتزی و خصوصیات فیتوشیمیایی اندازه گیری شد. نتایج به دست آمده نشان داد که اختلاف معنی داری بین غلظت های مختلف ساکارز از لحاظ تشکیل جنین های رویشی گیاه مارچوبه وجود دارد. در غلظت 9 و 15 درصد ساکارز به ترتیب بیش ترین و کم ترین تعداد جنین کروی و قلبی تشکیل شد. همچنین نتایج به دست آمده از تجزیه و تحلیل رگرسیون بیانگر آن بود که در غلظت 9 درصد ساکارز بیش ترین میزان رنگیزه های فتوسنتزی و نشاسته مشاهده شد. درنهایت در این پژوهش مشخص شد که بهترین غلظت موثر بر جنین زایی رویشی مارچوبه اکتاپلویید، غلظت 9 درصد ساکارز می باشد.

    کلیدواژگان: توفوردی، جنین زایی، رنگیزه های فتوسنتزی، کربوهیدرات
  • معصومه جعفری، علی اکبر شکوهیان*، اسماعیل چمنی، اکبر قویدل صفحات 843-855

    به منظور بررسی اثر اسید استیک بر pH محلول غذایی آهن (سکوسترین و نانو کود) و تاثیر آن بر ویژگی های کمی و کیفی توت فرنگی رقم ’دیامنت‘، این پژوهش به صورت کرت های دوبار خرد شده در قالب طرح بلوک های کامل تصادفی با 3 تکرار در ایستگاه تحقیقاتی دانشگاه محقق اردبیلی در طی سال های 1394 تا1396 به اجرا در آمد. تیمارهای آزمایش شامل محلول پاشی سطوح آهن (سکوسترین 25 گرم و نانو 1 گرم) درکرت هایی اصلی، سطوح اسید استیک (شاهد، 1، 2و 3 درصد) در کرت های فرعی و سطوح صابون کشاورزی مویان (شاهد و 5/7 درصد) در کرت هایی فرعی فرعی قرار گرفتند. نتایج این پژوهش نشان داد که اثر متقابل سه جانبه محلول پاشی اسید استیک با آهن همراه با صابون کشاورزی بر میانگین غلظت آهن برگ و تعداد میوه در سطح احتمال پنج درصد و در کلروفیل کل در سطح احتمال یک درصد معنی دار بود که بهترین نتیجه در صفت های ذکر شده از ترکیب تیماری 2 درصد اسید استیک با آهن سکوسترین همراه با 5/7 درصد صابون کشاورزی مویان حاصل شد. اثر متقابل دو جانبه اسید استیک و نوع آهن بر صفت های pH آب میوه، حجم میوه، وزن تر و خشک میوه در سطح احتمال پنج درصد و در عملکرد در سطح احتمال یک درصد معنی دار بودند. در صفت های حجم میوه، وزن تر میوه، وزن خشک میوه و عملکرد بهترین نتایج مربوط به ترکیب تیماری 2 درصد اسید استیک با کود آهن سکوسترین بود.،ولی در صفت pH آب میوه بهترین نتیجه از ترکیب تیماری 3 درصد اسید استیک با آهن سکوسترین بدست آمد. اثر متقابل دو جانبه عنصر آهنو صابون کشاورزی بر میزان مواد جامد محلول در سطح احتمال پنج درصد و اسیدکل میوه ی توت فرنگی در سطح احتمال یک درصد معنی دار بودند. در مورد صفت های مواد جامد محلول و اسیدیته قابل تیتراسیون، تیمار آهن سکوسترین و صابون کشاورزی مویان، بهترین نتیجه را داشتند. با توجه به نتایج حاصل از این بررسی، ترکیب تیماری 2 درصد اسید استیک با آهن سکوسترین همراه با 5/7 درصد صابون کشاورزی مویان به دلیل کاهش کشش سطح برگ موجب بهبود قدرت جذب آهن محلول غذایی و افزایش ویژگی های کمی و کیفی توت فرنگی توصیه می گردد.

    کلیدواژگان: کلروفیل، عملکرد، ویتامین ث
  • مهدی مرادی*، حسین نستری نصرآبادی، کمال قاسمی بزدی صفحات 857-867

    آویشن از مهمترین گیاهان دارویی است که کاربردهای وسیعی در صنایع دارویی، غذایی، آرایشی و بهداشتی دارد. پژوهش های سیتوژنتیکی، نقش مهمی در تعیین قرابت گونه ها ایفا می کند و به عنوان اولین تجزیه فیلوژنی و تکامل گروه های خویشاوند مطرح است. تعداد، اندازه و شکل کروموزوم از فاکتورهای مهم در بررسی تکامل هستند. در اصلاح ژنتیکی هر گونه گیاهی داشتن اطلاعات کافی در خصوص سطح پلوییدی و ویژگی های کاریوتیپی از مهم ترین نیازهای اولیه اصلاح گران می باشد. در این مطالعه ویژگی های کاریوتیپی برخی گونه های آویشن متعلق به بخش Serpyllum و زیر بخش Kotschyani مورد مطالعه قرار گرفت. در این مطالعه از سلول های مریستم ریشه چه و در مرحله متافاز میتوز برای بررسی ویژگی های کروموزومی و کاریوتیپی استفاده شد. بر اساس نتایج، عدد پایه کروموزومی در اکثر گونه ها 15=x و در برخی گونه ها 14=x بود. دو سطح پلوییدی (دیپلویید و تتراپلویید) در میان گونه های مختلف مشاهده شد. کروموزوم ها در اکثر گونه ها، به صورت متاسانتریک و ساب متاسانتریک بودند. بر اساس تقارن درون کروموزمی (A1 و TF) برخی جمعیت های گونهThymus eriocalyx  متقارن ترین و ابتدایی ترین کاریوتیپ و گونه های Thymus lancifolious وThymus fedtschenkoi نامتقارن ترین و کامل ترین کاریوتیپ را دارا بودند و بر اساس تقارن بین کروموزمی (A2) گونه Thymus eriocalyx دارای نامتقارن ترین کاریوتیپ بود. بر اساس جدول دوطرفه استیبنز اکثر جمعیت ها در کلاس 1A و 1B قرار گرفتند ولی در جمعیت های گونهT. lancifolious کلاس 2A و3B  نیز مشاهده شد. نتایج حاصل از این مطالعه می تواند برای درک بهتر جایگاه تاکسونومیکی و برنامه های اصلاح و اهلی سازی مفید باشد.

    کلیدواژگان: آویشن، تاکسونومی، زیر بخش kotschyani، سیتوژنتیک
  • حسین ذاکری، زهرا رودباری* صفحات 869-883

    سیلیسیم عنصری ضروری برای رشد گیاه نیست اما نقش آن در بهبود عملکرد به واسطه کاهش تنش های محیطی و ماندگاری محصول بسیار حایز اهمیت است. از سویی در تولید سبزیجات گلخانه ای، سودآوری وابسته به عملکرد بالا و میزان کیفیت در واحد سطح می باشد که می تواند با مدیریت صحیح هرس ساقه افزایش یابد. لذا به منظور بررسی اثر محلول پاشی کود سیلیسیم از منبع کلات سیلیسیم در مراحل مختلف رشد گیاه و تربیت بوته در گیاه بادمجان، آزمایشی گلخانه ای در محیط خاکی به صورت کرت های خرد شده در قالب طرح بلوک کامل تصادفی در 3 تکرار در منطقه میناب اجرا شد. در این آزمایش، مصرف کود سیلیسیم به عنوان فاکتور اصلی در 4 سطح (صفر و 2 در هزار در فاز رویشی، 2 در هزار در فاز زایشی و 2 در هزار در دو فاز رویشی و زایشی) و نوع هرس به عنوان فاکتور فرعی نیز در 4 سطح (بدون هرس، هرس دوشاخه، هرس سه شاخه و هرس چهارشاخه) اعمال شد. نتایج نشان داد که شیوه تربیت بوته با تاثیر مثبت بر طول میوه، ارتفاع بوته، وزن میوه منجر به افزایش متوسط عملکرد بوته از 720 گرم به 1300 گرم در هر چین شد. همچنین محلول پاشی سیلیسیم از طریق افزایش غلظت سیلیسیم موجود در گیاه و تاثیر مثبت بر تعداد میوه در بوته سبب افزایش 64 درصدی عملکرد بوته نسبت به عدم محلول پاشی سیلیسم شد. درصد افت وزن میوه نیز از 10 درصد در شرایط بدون دریافت سیلیسیم به 1 درصد کاهش معنی داری یافت. اثر متقابل محلول پاشی با سیلیسیم در دو مرحله رویشی و زایشی و تربیت بوته به صورت چهار شاخه کاهش درصد آلودگی قارچی را به دنبال داشت. لذا مصرف سیلیسیم در دو مرحله رویشی و زایشی به ویژه در گلخانه های سنتی فاقد سیستم های تهویه مناسب همراه با هرس چهار شاخه قابل توصیه است.

    کلیدواژگان: افت وزن میوه، سبزیجات گلخانه ای، عناصر مفید، هرس شاخه
  • مهشید غفوری، فرهنگ رضوی*، مسعود ارغوانی، ابراهیم عابدی قشلاقی صفحات 885-901

    جلبک قهوه ای جزو زیست محرک هایی است که بدون اثرات مخرب زیست محیطی در تولید محصولات باغی و زراعی مورد استفاده قرار می گیرد. این پژوهش به منظور بررسی تاثیر تیمار جلبک قهوه ای به صورت محلول پاشی بر روی شاخه، برگ و میوه بر برخی خصوصیات کیفی و فعالیت آنتی اکسیدانی میوه کیوی رقم ’هایوارد‘ به صورت فاکتوریل (فاکتور اول: محلول پاشی جلبک قهوه ای در چهار سطح (صفر، 1، 2 و 3 گرم در لیتر) در سه زمان 110، 125 و 140 بعد از مرحله تمام گل؛ فاکتور دوم: زمان انبارمانی در 4 سطح صفر، 30، 60 و 90 روز پس از انبارمانی) بر پایه طرح بلوک های کامل تصادفی با سه تکرار انجام شد. میوه های تیمار شده به مدت 90 روز در شرایط انباری با دمای 1 درجه سلسیوس و رطوبت نسبی 90 درصد نگهداری شدند و به صورت ماهیانه مورد ارزیابی قرار گرفتند. نتایج بدست آمده حاکی از تاثیر معنی دار تیمار عصاره جلبک قهوه ی بر صفات مورد ارزیابی بود. تیمار عصاره جلبک قهوه ای موجب حفظ سفتی بافت میوه، ویتامین ث، ظرفیت آنتی اکسیدانی، فنل، فلاونویید کل و آنزیم فنیل آلانین آمونیالیاز (PAL) در مقایسه با تیمار شاهد شدند. تیمار 3 گرم در لیتر جلبک قهوه ای بهترین تاثیر را در بین تیمارهای اعمال شده در حفظ سفتی (40/40 درصد)، درصد کاهش وزن میوه (87/41 درصد)، اسید قابل تیتراسیون (37/25 درصد)، ویتامین ث (26/33 درصد) ظرفیت آنتی اکسیدانی (70/26 درصد) ، فنل کل (17/81)، فلاونویید کل (67/103 درصد) و فعالیت آنزیم PAL (75/153 درصد) نسبت به شاهد در 90 روز انبارمانی داشت. با توجه به اثرات مثبت تیمار عصاره جلبک قهوه ای بر حفظ کیفیت و افزایش ماندگاری میوه کیوی در طی دوره انبارداری، چنین به نظر می رسد که کاربرد این ترکیب در مقیاس وسیع به عنوان یک راهکار مناسب جهت افزایش کیفیت میوه کیوی رقم هایوارد قابل توصیه باشد.

    کلیدواژگان: آنزیم فنیل آلانین آمونیالیاز، ظرفیت آنتی اکسیدانی، فلاونوئید و فنل کل، محلول پاشی
  • مژده اسکو، عزیزاله خندان میرکوهی*، روح انگیز نادری صفحات 903-915

    جهت ارزیابی تاثیر سطوح مختلف نیترات آمونیوم بر شاخص های رشدی و فیزیولوژیکی گیاه سجافی (Chlorophytum comosum) آزمایشی بر پایه طرح بلوک های کامل تصادفی با 4 تیمار و 3 تکرار به اجرا درآمد. از چهار سطح مختلف نیترات آمونیوم (100 (به عنوان شاهد)، 200، 400 و600 میلی ‎گرم در کیلوگرم خاک) استفاده شد. تیمارها، ماهانه و به صورت چالکود اعمال گردید. صفات مورد بررسی شامل صفات مورفولوژیک (ارتفاع، تعداد برگ، تعداد دستک، وزن تر اندام هوایی، وزن خشک اندام هوایی، وزن تر ریشه، وزن خشک ریشه، حجم ریشه، عمق ریشه، طول ریشه، وزن گلدان، سطح برگ) و صفات فیزیولوژیک (کلروفیل کل، مقدار پروتیین کل، مقدار نیترات موجود در بافت و میزان پرولین) بود و همچنین آنالیز بسترکشت قبل از شروع آزمایش انجام شد. نتایج مقایسه میانگین نشان داد که اثر سطوح مختلف نیترات آمونیوم بر همه صفات مورد ارزیابی به جز وزن گلدان، عمق ریشه، طول ریشه و حجم ریشه معنی دار بود. با افزایش سطوح مختلف تیمار، ارتفاع، تعداد برگ، وزن تر اندام هوایی، وزن خشک اندام هوایی، وزن تر ریشه، وزن خشک ریشه و سطح برگ افزایش یافت. بیشترین میزان کلروفیل، پروتیین و نیترات بافت در تیمار 400 میلی گرم نیترات آمونیوم مشاهده شد و با افزایش کاربرد نیترات آمونیوم مقدار آنها کاهش یافت. بیشترین مقدار پرولین (20/11 میکروگرم بر میلی لیتر) در تیمار 600 میلی گرم نیترات آمونیوم و کمترین مقدار (57/3 میکروگرم بر میلی لیتر) در تیمار شاهد مشاهده شد. با توجه به نتایج بدست آمده تیمار 400 میلی گرم نیترات آمونیوم موجب افزایش شاخص های رشد و عملکرد و افزایش جنبه زینتی گیاه سجافی به عنوان یک گیاه برگ زینتی گردید.

    کلیدواژگان: پروتئین، شاخص های رشد، عملکرد، کلروفیل
  • محدثه پیری، زهره جبارزاده* صفحات 917-936

    امروزه اهمیت اقتصادی و ارزش گیاهان زینتی به‏ویژه گل های شاخه بریده در جهان افزایش پیدا کرده است و ماندگاری گل ها یکی از موضوعات مهم در تجارت گل های شاخه بریده است، بنابراین ارایه راه کارهایی که باعث بهبود کیفیت گیاهان و افزایش ماندگاری آن ها شود امری ضروری است. به این منظور در پژوهش حاضر تاثیر اسپرمیدین، اسیدسالیسلیک و سدیم نیتروپروساید بر رشد و کیفیت گل و همچنین عمرگلجای گیاه لیزیانتوس رقم ‘Mariachi Blue’ ، در قالب طرح کاملا تصادفی با 4 تکرار که هر تکرار شامل 2 گلدان بود در شرایط کشت بدون خاک، در گلخانه پژوهشی دانشکده کشارورزی دانشگاه ارومیه بررسی شد. تیمارهای مورد بررسی شامل اسپرمیدین در غلظت های 5/0، 1 و 2 میلی مولار، اسید سالیسلیک در غلظت های 5/0، 1 و 5/1 میلی مولار، سدیم نیتروپروساید در غلظت های 50، 100 و 200 میکرومولار و تیمار شاهد (محلول پاشی با آب مقطر) بودند. نتایج به دست آمده نشان دادند که تیمارهای مورد استفاده موجب افزایش معنی دار برخی شاخص های مورفولوژیکی، رنگیزه های فتوسنتزی و عمر گلجای نسبت به شاهد شدند. با توجه به نتایج حاصل، اسیدسالیسلیک باعث افزایش تمامی شاخص های اندازه گیری شده (به غیر از وزن تر گل) نسبت به شاهد شد. اسپرمیدین، طول ساقه، وزن تر برگ، وزن تر و خشک گل، طول و قطر گل، شاخص کلروفیل، کلروفیل b، کاروتنویید و عمر گلجای را نسبت به شاهد افزایش داد و سدیم نیتروپروساید نیز به غیر از سطح برگ، وزن خشک برگ، کلروفیل a و عمر گلجای در بقیه شاخص ها تاثیر مثبتی داشت. به طور کلی در این پژوهش، اسیدسالیسلیک و اسپرمیدین در غلظت 1 میلی مولار و  سدیم نیتروپروساید در غلظت های 50 و 100 میکرومولار موثرترین تیمارها در بهبود شاخص های رشدی، گلدهی و عمر گلجای گل لیزیانتوس بودند.

    کلیدواژگان: پلی آمین، تنطیم کننده رشد، قطر گل، میزان کلروفیل، نیتریک اکسید
  • مهناز کریمی*، فاطمه سلیمی، علی پاکدین پاریزی صفحات 937-948

    پژوهش حاضر به منظور ارزیابی اثر کندکننده های رشد و روش کاربرد آن ها در تولید گیاه پاکوتاه لیلیوم (رقم آیلاینر) انجام گرفت. آزمایش به صورت فاکتوریل در قالب طرح کاملا تصادفی با دو فاکتور شامل استفاده از کندکننده های رشد (سایکوسل؛ صفر، 1000 و 1500 میلی گرم در لیتر) و یونیکونازول؛ صفر، 5 و 10 میلی گرم در لیتر) و نحوه کاربرد این مواد (محلول پاشی برگ و غوطه وری سوخ) انجام شد. با توجه به نتایج به دست آمده اثر تیمارها و نحوه کاربرد آن ها بر بیشتر صفات مورد بررسی معنی دار بود، به طوریکه کمترین ارتفاع ساقه با 67 درصد کاهش نسبت به شاهد، در تیمار محلول پاشی یونیکونازول با غلظت 10 میلی گرم در لیتر به دست آمد. همچنین بیشترین کلروفیل کل در همین تیمار به روش غوطه وری ثبت شد. کوتاه ترین زمان تشکیل غنچه در تیمار سایکوسل با غلظت 1500 میلی گرم در لیتر مشاهده شد. غوطه وری سوخ ها در کاهش زمان تشکیل غنچه در مقایسه با محلول پاشی موثرتر بود. قطر گل در تیمار 1500 سایکوسل به روش غوطه وری در حداکثر بود اما با تیمار 1000 سایکوسل به روش غوطه وری و تیمار یونیکونازول 10 میلی گرم در لیتر محلول پاشی تفاوت معنی داری نداشت. فعالیت آنزیم کاتالاز نیز در گیاهان محلول پاشی شده بیشتر از تیمارهای غوطه وری بود. بیشترین میزان فعالیت این آنزیم با 23/54 درصد افزایش نسبت به تیمار شاهد در تیمار سایکوسل 1500 میلی گرم در لیتر مشاهده شد. همچنین بیشترین فعالیت آنزیم گایاکول پراکسیداز در گیاهان محلول پاشی شده با 1000 میلی گرم در لیتر سایکوسل به دست آمد که تفاوت معنی داری با تیمار 1500 سایکوسل در روش غوطه وری نداشت. لذا با توجه به اینکه تیمار یونیکونازول 10 میلی گرم در لیتر تاثیر معنی داری در مقایسه با دیگر تیمارها در کاهش ارتفاع نشان داد، بنابراین استفاده یونیکونازول با غلظت 10 میلی گرم در لیتر به صورت غوطه وری و محلول پاشی در تولید گیاه گلدانی لیلیوم توصیه می شود.

    کلیدواژگان: ارتفاع گیاه، بازدارنده های رشد، فعالیت آنزیمی، گلدهی، کلروفیل
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  • S.F. Motevalian, B. Abedy *, Y. Selahvarzi, A. Tehranifar Pages 735-745
    Introduction

     Major problems of pomegranate production, which is common in almost all of the world's pomegranate growing areas, especially in warm and dry regions, is the splitting of fruit, which is the most damaging to gardeners after pomegranate fruit moth. On the other hand, different studies indicate that girdling affects the quantitative and qualitative characteristics of different fruit trees. In the gird, the trunk skin must be completely removed so that the upper to lower skin relationship is completely cut off. The raw material that is absorbed by the root and rising through the xylem is transformed into a sap in the leaf, and in the return path through the phloem, it hits the barrier and accumulated above the wound site. Due to this process, sugar and plant hormones and starch reach the upper part of the wound girdling in trees for various purposes, such as raising the percentage of fruition of the plant, increasing size and increasing the quality and accelerating the fruition is done.

    Material and Methods

     An experiment was conducted to investigate the effect of girdling time on quantitative and qualitative properties of two red peel sweet and tart varieties in the Mahdi Shahr city, Semnan province. The girdling was taken at three full bloom days, two months after full bloom and four months after full bloom. To do a girdling, a double-edged knife was plunged into the trunk, and the ring-like cutting was done around the trunk. So that the layer of bark was cut from the trunk with a diameter of less than 2 to 3 mm continuously and separated from the trunk completely, so that the relationship between the top and the bottom was cut off. To evaluate qualitative and quantitative traits, 3 fruits were selected from the northern, southern and middle parts of each tree and transferred to the laboratory for measuring morphological and physiological traits. Physiochemical traits including pH, titratable acidity content, total soluble solids and morphological traits including weight, volume, average weight of 100 aryls and percentage of fruit juice, Ariel seed weight percentage, and split percentage were investigated.

    Results and Discussion

     The results indicated that girdling at full bloom and two months after full bloom significantly reduced the percentage of fruit blooming in both cultivars compared to the control (non-girdling) treatment. Also, among the studied cultivars, percentage of splitting in red peel was higher than that of sour-sweet. In addition, girdling at full bloom and four months after bloom was able to increase weight, volume, and average weight of 100 aryls. Among two studied cultivars, sour-sweet showed higher soluble solids content and titratable acid percentage than red peel. It can be stated that photosynthetic materials in the crown of the tree are blocked by conducting a loop on the branch of the plant and prevent the transfer of these materials to the root. This allows the carbohydrates from photosynthesis to be transferred to fruits that are growing. As a result, the fruit grows more and subsequently increases its weight, volume, and number of aryls. In addition, the growth of root is reduced as a result of girdling and water, mineral salts, as well as growth regulators to the canopy and terminal meristem of the plant are slowed down, thereby significantly decreasing vegetative growth to be seen in the tree. Subsequently, with decreasing vegetative growth in the tree, the carbohydrate which is produced in the leaves is allocated to the growing fruits. This also increases the weight and volume of fruit in the tree. Since the girdling treatments are associated with meiosis (in full blooming stage) and in the stage of the growing of fruits cells (4 months after full bloom), it can be justified to enhancement of the weight and reduction of splitting percentage in the fruits of trees which is girdled. The main reason for this difference is the tension entered into the girdled trees at the interval between the application of the treatment and the wound healing.

    Conclusion

     According to the results of this study, it was found that the process of girdling results in weight and volume enhancement of the fruit. In addition, the quantitative and qualitative traits investigated in the experiment were different in the two cultivars of red peel sweet and sour-sweet. In addition, girdling was effective on the pomegranate splitting, which is one of the important issues in the plantation of this fruit. However, the timing of the girdling at the full bloom and the four months after full blooming had the greatest effect on reduction of the severity of this complication.

    Keywords: Pomegranate, Splitting, Trunk girdling
  • B. Kaviani *, M. Jamali, M.R. Safari Motlagh, A.R. Eslami Pages 747-761
    Introduction

     Pears have a high nutritional and economic value worldwide. One of the major problem in growing pear cultivars is their late fertility on seed bases. To solve this problem, using asexual propagation methods can lead to the production of root trees. Cuttings are commonly used for proliferation either softwood, semi-hardwood or hardwood. Clonal propagation is considered proper in rapid propagation of shrubs and trees species. Adventitious root formation in stem cuttings is a crucial physiological process for vegetative propagation of many plant species. Rooting ability of tree species through stem cuttings is affected by several factors particularly plant growth regulators. Rooting of pear stem cuttings is time consuming. Auxin is effective in stimulating root formation on cuttings. The most widely used auxins in rooting of stem cuttings are indole-3-butyric acid (IBA) and naphtaleneacetic acid (NAA). Of these two auxins, IBA is the most widely used root promoting chemical, because it is nontoxic over a wide range of concentrations. Applied concentration is an important factor. Typically, a concentration of 2000 to 4000 ppm will result in good rooting for most shrubs and trees.

    Materials and Methods

     In this experiment, pear (Pyrus communis) was used as mother plants. Stem cuttings were used as plant materials in this experiment. The effect of different levels of indolebutyric acid (IBA) and naphthalene acetic acid (NAA) was studied on the rooting of pears in a factorial experiment based on a randomized complete block design with 16 treatments and 4 replications. The experimental treatments included IBA and NAA at the rates of 0, 1000, 2000 or 4000 mg L-1. Rooting percentage, rooting time, root number, root length, root volume, plant height, leaf number and fresh and dry weights of cuttings were measured after about 130 days.

    Results and Discussion

     The results showed that the highest rooting (3.56 per seedling) was observed in cuttings treated with 4000 mg L-1 IBA. Also, the highest root number was obtained from the treatment of 1000 mg L-1 NAA and 2000 mg L-1 IBA with an average number of 0.16 roots per plant. According to the means comparison for the simple effect of IBA on the rooting time, the highest rooting time was related to the application of 4000 mg L-1 IBA.  The results revealed that plants treated with 4000 mg L-1 NAA and 2000 mg L-1 IBA grew the longest roots. Also, ANOVA showed that among the applied factors, only the simple effect of IBA was significant on root volume. Means comparison for the simple effect of IBA on root volume showed that the highest was related to the application of 2000 mg L-1 IBA. According to the means comparison for the interactive effect of IBA × NAA on cutting fresh weight, the highest fresh weight was, on average, 8.36 g in plants treated with 4000 mg L-1 NAA and 2000 mg L-1 IBA. As well, means comparison the effect of IBA × NAA on cutting dry weight showed that the highest dry weight was 15.9 g related to the application of 4000 mg L-1 NAA × 2000 mg L-1 IBA. It was also observed that 2000 mg L-1 NAA × 1000 mg L-1 IBA was related to the longest cutting with an average length of 2.82 cm. Finally, plants treated with 4000 mg L-1 NAA and 2000 mg L-1 IBA produced the highest number of leaves (15.9 g, on average). One of the effective factors in the success of vegetative propagation of plants with stem cuttings, especially woody plants with hard-rooting stems, is the production of more roots in a short time. Plant growth regulators, including auxins, play an important role in this regard. The effect of auxins on the percentage and number of roots produced on stem cuttings has been shown by many researchers on various plants, including plants with hard-rooting cuttings particularly in trees. The most widely used auxins in this regard are IBA and NAA, respectively. The individual or combined effect of auxins for successful rooting depends on a number of factors, including plant type, cuttings type, cuttings size, cuttings age, and the time of year the cuttings were removed. In the present study, the combined effect of IBA and NAA had the greatest effect on most of the measured traits.

    Keywords: Auxin, Fruit plants, Hardwood cuttings, Plant growth regulators, Rosaceae family
  • R. Raei, V. Akbarpour *, M.A. Bahmanyar Pages 763-776
    Introduction

     Fertilizer management is one of the main factors in achieving sustainable agriculture. Therefore, the integrated agricultural system recommends the use of organic matter along with the optimal use of chemical fertilizers. This method is a balanced way to improve the physical and chemical properties of the soil, which leads to improved growth and increased plant yield. Organic fertilizers, especially livestock manures, have higher levels of organic matter than chemical fertilizers, and can be considered as sources of nutrients, especially nitrogen, phosphorus and potassium. One of these organic fertilizers is poultry manure, which in addition to having macro and micro elements (manganese, iron, copper, and boron) is one of the cheapest fertilizers compared to other fertilizers used. It is also richer in terms of nitrogen than other animal fertilizers. Soil fertility is the factor that change the amount of active substances and essential oils. Micronutrients such as zinc, although needed in small amounts by plants, play an important role in plant growth and development. The application of zinc sulfate fertilizer improved the quantitative and qualitative attributes of basil, peppermint, sage, and rosemary. Researchers stated that the application of a combination of chemical fertilizers and poultry manure has increased the yield of garlic essential oil. Therefore, in recent years, integrated plant nutrition management has been discussed. Integrated plant nutrition management is based on the simultaneous application of organic, chemical, and biological fertilizers. Because organic fertilizers alone can’t provide the needs of high-yielding plants. Combined application of organic, chemical, and biological fertilizers can improve the physical and chemical conditions of the soil and increase organic carbon and nutrients.  Savory is an aromatic medicinal plant from the mint family. This plant has a lot of essential oils and is very important in the food, pharmaceutical, and health industries. The aim of this study was to investigate the role of poultry manure and zinc sulfate in the cultivation of savory.

    Materials and Methods

     The present experiment was performed as a factorial in a completely randomized design with 3 replications. The factors consisted of poultry manure with four levels (0, 3, 6, and 9 t.ha-1) and the second factor zinc sulfate with four levels (0, 50, 100 and 150 mg.kg-1 soil).

    Results and Discussion

     According to the obtained results, the effect of poultry manure, zinc sulfate, and their interaction on most of the studied traits was significant. The highest height was observed in the treatment of poultry manure of 9 t.ha-1 + zinc sulfate in 100 mg. kg-1 soil, which showed an increase of 79.26% compared to the control, and the lowest height belonged to the control treatment. The total chlorophyll in the chicken manure treatment of 6 t.ha-1 + zinc sulfate in 150 mg. kg-1 had a significant increase compared to the control. The highest amount of leaf nitrogen was obtained in the treatment of poultry manure of 9 t.ha-1 + 50 mg.kg-1 with an increase of 82.03% compared to the control. Zinc element was observed with a 222.75% increase in poultry manure treatment of 9 t.ha-1 + 150 mg.kg-1. Poultry manure treatment of 6 tons per hectare + 150 mg.kg-1 with 261.53% increase compared to the control contained the highest percentage of essential oil.

    Conclusion

     The results of the study showed that the use of combined ratios of poultry organic fertilizer and zinc sulfate has been effective in improving vegetative attributes, available plant elements, and essential oil content.

    Keywords: Essential oils, Medicinal plants, Nutrition, Organic manure, Phytochemical traits, Zinc sulfate
  • M. Shahabi, S. Rastegar * Pages 777-789
    Introduction

     Narcissus (Narcissus tazetta) has high demand in flora markets due to its beauty, having a multi-floret flowerhead and delicate fragrance. The appearance quality and vase life of cut flowers decreased after harvest due to flower senescence, loss of petals turgor, reduced water absorption, transpiration, fresh weight loss, and reduced water potential which reduces the economic and ornamental value of flowers at the consumer. One of the important reasons for the poor postharvest quality of Narcissus tazetta is the loss of turgor and their high sensitivity to browning of the petals. Browning mechanisms are chemically divided into enzymatic and non-enzymatic browning reactions. Enzymatic browning, which causes important reactions and discoloration, is one of the important factors affecting the quality and shelf life of fresh produce. Previous studies have shown that the activity of polyphenol oxidase (PPO) and peroxidase (POD) is positively correlated with browning during the postharvest storage of fruits and vegetables. Nitric oxide (NO) is recognized as a biological messenger in plants. It is a highly reactive gaseous free radical. Optimum NO levels could delay the climacteric phase of many tropical fruits and prolong the post-harvest shelf life of a wide range of horticultural crops by preventing ripening and senescence. Nitric oxide also could prevent the activity of PPO, phenylalanine ammonialyase (PAL) and POD, and keep the highest activity of superoxide dismutase (SOD).

    Materials and Methods

    Narcissus (Narcissus tazetta L. cv. Shahla e-Shiraz) cut flowers at their commercial maturity stage (Goose-neck) were harvested from a production field in Farse province and. then they were transported to the laboratory. Healthy and uniform cut flowers with the same number of buds, a similar size and growth status were selected. Cut flowers were subjected to pulsed treatment of sodium nitroprusside for 24 hours on two levels (25 and 50 μM) and then kept in containers. Samples were stored at 20 ± 2 °C, relative humidity of 70-60%, with light cycle of 12 hours light and 12 hours dark. In this experiment, various physiological and biochemical indices including apparent quality (wilting index), cell membrane stability index (%), petal relative water content (%), color index and browning using a colorimeter, relative weight using digital scale (g), flower diameter, PPO and POD were examined. 

    Results and Discussion

    Sodium nitroprusside treatment reduced the browning process by reducing the activity of POD and PPO enzymes. The effect of sodium nitroprusside was concentration-dependent. Sodium nitroprusside maintains membrane stability by protecting the membrane and preventing lipoxygenase activity and scavenging free radicals that have attacked the membrane. Sodium nitroprusside-maintained flower diameter due to its role in eliminating free radicals, delaying the aging process and maintaining flower quality. Discoloration and browning reactions of cut flowers reduce their appearance quality, leading to economic loss. The browning of the petals due to senescence is one of the important factors limiting the vase life of narcissus. It has been shown that PPO and POD are the key enzymes for the oxidation of the phenolic substrate (especially simple phenols) and the production of the brown compounds. It has also been suggested that the stability index of the cell membrane, which represents the ion leakage of the tissues, is diminished extremely as the longevity is increased. Another effective factor in determining the quality and vase life of cut flowers is the water-holding ability and water balance of the cut flowers petals. Changes in the cut flower fresh weight could also be regarded as one of the most important postharvest physiological disorders that affected the quality, vase life and commercial value of the cut flowers. Fresh weight loss, which is one of the most important reasons for the wilting of the flowers, is due to the less water uptake and more respiration rate.

    Conclusion

     Sodium nitroprusside treatment maintained the quality of Narcissus tazetta L. cv. Shahla e-Shiraz by increasing the relative water content of the petals and maintaining the cell stability index, as well as reducing the activity of browning enzymes (PPO and POD).Of course, the concentration used was very important.The best results were observed at lower concentrations (25 μM) of sodium nitroprusside.

    Keywords: membrane stability, Nitric oxide, peroxidase activity, polyphenol oxidase, Postharvest
  • H.R. Karimi *, N. Biniyaz, A.A. Mohammadi Mirik, M. Esmaeilizade, Z. Hatamean Pages 791-802
    Introduction

    Pomegranate (Punica granatum L.) from the family Punicaceae, is an important and exportable fruit crop in Iran. At present, Iran is the leading producer of this fruit followed by India, Turkey and Spain. As the main area under pomegranate cultivation in Iran are located in arid and semi-arid adjacent to desert regions. Low irrigation water quality, lime induced Fe chlorosis, soil salinity, nutrient imbalance and soil-borne diseases are the most limiting factors in this areas. Currently about 760 genotypes and cultivars of pomegranate have been identified, collected and growth in Pomegranate Research Institute in Yazd province, central Iran. In rich collection, it is likely that some genotypes are tolerant to adverse environmental conditions but neglected due to their low quality fruits. These genotypes could be evaluated and used as potential rootstocks. ‘Rabab-e-Neyriz’ is one of the most important pomegranate cultivar that is planted in parts of western south of Iran to gather ‘Khafr-e-Jahroom’ cultivar. Fruits in ‘Rabab-e-Neyriz’ cultivar are big with dark red color arils. In the last decades, there has been a tremendous towards using grafted/budded plants in fruit orchards. Moreover, the available reports indicate that rootstock could affect the tolerance of scion to soil borne diseases, lime-induced Fe-deficiency chlorosis and salinity stress that they can control with grafting on tolerance rootstocks. There are inadequate formations on the effects of rootstock on scion of pomegranate. The aim of the study was effects of three rootstocks; ‘Gorj-e-Dadashi’, ‘Gorj-e-Shahvar’ and ‘Post Ghermaz-e-Aliaghai’ on nutrient concentration of two pomegranate cultivars; ‘Rabab-e-Neyriz’ and ‘Khafr-e-Jahroom’; as scion.

    Material and MethodsIn

    order to investigate the interaction of rootstock and scion on nutrient uptake in two pomegranate cultivars ‘Rabab-e-Neyriz’and ‘Khafr-e-Jahroom’, research was performed in the form of a factorial experiment in complete randomized blocks design with scion factors at two levels (‘Rabab-e-Neyriz’and ‘Khafr-e-Jahroom’) and the rootstock on four levels (‘Post Ghermaz-e-Aliaghai’, ‘Gorj-e-Dadashi’, ‘Gorj-e-Shahvar’and without graft) with five repetitions. Omega grafting method was used to production grafting plants. One year grafting plants were planted on farm with 2.0 m apart within rows and 4.0 m apart between rows. Non grafting cuttings of scions that rooted same time with rootstocks were planted in farm as control. In the first summer leaf samples were collected to determine macro and micro elements. 

    Results and Discussion

    The results showed that the interaction of rootstock and scion is effective on the uptake of elements. The concentration of elements in the scion varied depending on the type of graft combination. The highest levels of phosphorus, potassium, and calcium of leaves were observed in the grafting plants of ‘Rabab-e-Neyriz’ scion on ‘Gorj-e-Dadashi’ rootstock, ‘Khafr-e-Jahroom’ scion on ‘Gorj-e-Dadashi’ rootstock, and ‘Rabab-e-Neyriz’ scion on ‘Gorj-e-Shahvar’ rootstock, respectively. Also, the highest amounts of iron (75 mg/g dry weight), manganese (65 mg/g dry weight), and copper (25 mg/g dry weight) were obtained from the grafting plants of ‘Rabab-e-Neyriz’ scion on ‘Gorj-e-Dadashi’ rootstock, ‘Khafr-e-Jahroom’ scion on ‘Gorj-e-Dadashi’ rootstock and, in both scions on ‘Gorj-e-Shahvar’ rootstock compared to non-grafted plants.  

    Conclusion

    The results of this research have shown that the amount of nutrients in the leaves of grafted pomegranate cultivars is not only influenced by the rootstock, but also by the genetics of the scion. The concentration of mineral elements in the scion is mainly related to the characteristics of the root system of rootstock, including the lateral and vertical expansion of the root, which increases the absorption of water and minerals. Due to the weaker root system, the ‘Post Ghermaz-e-Aliaghai’ has a lower concentration of mineral elements in the cultivars grafted on this rootstock. According to the results of the present study, the reason for the higher nutritional elements in plants grafted with the rootstocks of ‘Gorj-e-Dadashi’ and ‘Gorj-e-Shahvar’ can be attributed to the greater growth power of these roots  and their extensive root system. He attributed that wider research is recommended in this field.

    Keywords: Calcium, Grafting, Magnesium, Pomegranate, Potassium
  • D. Kazemi, M. Dehestani Ardakani * Pages 803-815
    Introduction

     Different aspects of light including intensity, quality (spectra), and duration (photoperiod) can influence plant growth and development. The growth and development of ornamental plants are also influenced by light intensity and quality. Energy saving in greenhouse production has received much attention lately. One reason for the interest in utilizing light quality to modulate plant growth and morphology is the recent development of light-emitting diodes (LEDs) as a lighting source in greenhouse production. Such small diodes can easily be placed close to the canopy and can be used to apply a narrow-band light spectrum to the plants. Specific requirements for light spectral distribution for specific processes like morphogenesis, photosynthesis, chlorophyll and anthocyanin synthesis have been determined in different species. The aim of the current study was to investigate the biophysical properties of chlorophyll fluorescence of Hypoestes phyllostachya plants in response to different light spectra

    .Materials and Methods

     Research experiments were conducted on Hypoestes phyllostachya in a completely randomized design with six treatments of different light quality and three replications. The seeds were planted in plugs and in a mixture of 70% peat moss and 30% perlite. Seedlings were grown in natural greenhouse (control) and LED (100% Blue, 15% Blue +85% Red, 30% Blue +70% Red, 15% Blue +65% Red + 20% White and 30% Blue +50% Red + 20% White). Since the main goal of the study was to compare the effect of LED light quality with sunlight in conventional greenhouse conditions. The LED treatments were applied from fourth month old seedlings until five weeks in a growth chamber with the light/dark regime of 15/9 hours, 23±5°C temperature, and 65±5% relative humidity. While, their pots in the greenhouse with 55±5 mol.m-2.d-1 DLI, 21±5°C average daily temperature and 65±5% relative humidity (Data logger 8808 temp. + RH) were regarded as the control treatment. After five weeks, the fluorescence chlorophyll was measured.Selected leaves were dark-adapted prior to the measurements and OJIP protocol was applied using a fluorometer (FluorPen FP 100-MAX, photon system instruments, Drasov, Czech Republic). The fluorescence measurement was performed using a saturating. FluorPen software was used to extract data from the original measurement. Data extracted were used to analyze the following data according to the equations of the JIP test: fluorescence intensities at 50 μs (F 50 μs, considered as the F0), 2 ms (J-step denoted as FJ), 60 ms (I-step, FI), and maximum fluorescence intensity (FM, FP). The JIP-test was used to quantify the amount of energy that flow via the PSII. Performance index was measured on the absorption basis (PIABS, a multi-parametric expression). Probability that a trapped exaction promote an electron in electron transport chain (ETC) beyond the primary acceptor Quinone (QA−), maximum quantum efficiency of PSII (FV/FM), specific energy fluxes per reaction center (RC) for energy absorption (ABS/RC), trapped energy flux (TR0/RC), electron transport flux (ET0/RC) and dissipated energy flux (DI0/RC) were calculated according. Finally, the data were statistically analyzed with SAS (9.4) software package, and the means were compared by LSD test at p < 0.05 level.  

    Results and Discussion

     Fast Chl fluorescence induction curves (OJIP) was the main parameters used for the screening of different light treatments. OJIP test is shown to be a proxy to detect PSII bioenergetics and indicates changes in the status and function of PSII reaction centers, antenna, as well as in donor and acceptor sides of PSII. The maximum quantum yield of PSII (FV/FM) and relative maximal variable fluorescence (Fm/F0), significantly increased in 15% Blue +85% Red, 30% Blue +70% Red, 15% Blue +65% Red + 20% White. PIABS, one of the OIJP test parameters that provide valuable awareness about photosynthtic performance, considerably decreased under control and 30% Blue +50% Red + 20% White treatment. Unlike PIABS, ET0/RC did not show a significant difference under different treatments. The specific energy fluxes per RC for energy absorption (ABS/RC) significantly increased under control and 30% Blue +50% Red + 20% White treatment. TR0/RC increased in plants under control and 30% Blue +50% Red + 20% White treatment. Treated plants under 15% Blue +85% Red and 30% Blue +70% Red showed the lowest in dissipated energy flux (DI0/RC).  During an ideal condition without any additional stress, the total PSII pool can be completely inactivate and retrieve without a detectable photoinhibition.Conclusion When plants exposed to 100% Blue and 30% Blue +50% Red + 20% White treatments as well as in control plants, FM/F0, FV/FM and PIABS significantly decreased.  Also ABS/RC, TR0/RC and DI0/RC, significantly increased.

    Keywords: Photosynthesis, Leaf chlorophyll fluorescence, light quality, Light spectra, Plantlet
  • M.E. Naddaf, E. Ganji Moghadam *, Gh. Rabiei, A. Mohammadkhani Pages 817-827
    Introduction

     Sweet Cherry (Prunus avium) belongs to the Rosaceae family, which due to vegetative propagation problems, in vitro propagation is recommended to increase mass and disease-free production. Micropropagation has many advantages over other vegetative methods. Although the most suitable organ that preserves the genetic characteristics of the cultivar is bud meristem, plant regeneration from meristem culture is difficult in many species of woody plants, so micro-grafting is a suitable technique to overcome these problems. The aim of this study was to investigate the effect of scion size and origin of commercial sweet cherry cultivars interact with micrografting on the vegetative rootstocks.

    Materials and Methods

     In this study, factorial experiment was used as a test unit in a completely randomized design (CRD) with two factors in five replications and ten seedlings per replication. The first factor was cultivar in seven levels (B: Bing, D: Dovomres, H: Haj Yousefi, P: Pishres, S: Siah- Mashhad, T: Takdaneh, Z:  Zard) and the second factor was scion type in four levels (M1R1: 2 mm in vivo explant, M2R1: 5 mm in vivo explant , M1R2: 2 mm in vitro explant and  M2R2: 5 mm in vitro explant). To prepare the scion, 1.5 to 2 cm long explants were isolated from shoot tips and then disinfected with 75% ethanol and 20% Sodium hypochlorite. After rinsing with distilled water, the shoot tips with 2 and 5 mm length were extracted for in vivo explants. In vitro explants were obtained from shoo tips that was previously established in MS culture medium with supplement of 1 mg.l-1 of BAP. The meristems were prepared in 2 and 5 mm and used as in vitro explant.  5 cm length in vitro shoots of sweet cherry ‘Gisella 6’ was used as rootstock. Micro-grafting was performed according to the standard method for sweet cherries. Micro-grafted plantlets were transferred to MS medium supplemented with 1 mg.l- l BAP, and kept under low light (100 lux) condition for one week, then  transferred to growth chamber at 27.1 °C photoperiods 16/8 hrs light/darkness (1500 lux). In order to induce root, grafted plantlets were transferred to Perlite: MS medium supplement with 1 mg.l- l IBA. After rooting, plants were placed in polyethylene pots containing perlite: peatmoss (1:1) for acclimation. Micro-grafting success indices were recorded in each of the micro-grafted plantlets. The data were analyzed by SAS statistical software (9.1) and the means were compared by Duncan's multiple range test (1 and 5 % of probability levels).

    Results and Discussion

     The results showed that in all indices there was a significant difference between scion types and cultivar scion type interactions except grafting time, but there was no difference between cultivars (except longitudinal growth of scion). Among the scion types, the 5 mm in vitro scion (M2R2) had the highest micro-grafting success rate (42%), number of leaves (3.7), longitudinal growth (6.3 cm) and taken grafting time (two days). Finally, in successful micro-grafted plants, ‘Pishres’ cultivar had better results in rooting (32.8%) and ‘Zard’ cultivar in acclimation (3.4%) traits. Probably the presence of leaves led to better nutrient supply and surface contact, so it mostly improved the success of micrografting technique. In this study, micro-grafting success indices were lower than previous reports using seedling rootstocks. This might be due to difficult grafting operations, poor rootstock-scion communication, low physiological activity, and high in vitro oxidase activity. In the type of scion, micro-grafting success rate of 5 mm in vitro scions (include leaf primordia), was better than 2 mm scions (without leaf primordia). These results were consistent with most reports in sweet cherries and other stone fruit that were more successful in micro-grafting using larger in vitro explant.

    Conclusion

     Based on our results, it can be concluded that the micro-grafting method in sweet cherry micro-propagation is a fast practical method with high potential for production and regeneration of healthy orchards, which is also possible for other cultivars. In micro-grafting success, in vitro explants are preferable to explants taken directly from in vivo mother trees, and the use of larger explants for scion is recommended due to the presence of leaf primordia in micro-grafting success. However, smaller-size explants are more likely to produce healthy plants.

    Keywords: Acclimation, Leafy primordia, Shoot tips, Tissue culture, Virus-free
  • Z. Toosi, S.J. Mousavizadeh *, K. Mashayekhi, M. Alizade Pages 829-842
    Introduction

     Asparagus, scientifically named Asparagus officinalis. L is a perennial plant belonging to the Asparagaceae family. Asparagus is a large genus in this genus that has about 200 species. The most important species for agricultural purposes is A. officinalis. Somatic embryogenesis is the formation of an embryo from an-asexual cell in vitro that similar to a seed embryo, is able to develop into a complete seedling. Somatic embryogenesis is a complex molecular and biochemical process based on cellular potentiogenicity and a model in the study of plant growth. In this unique process of embryogenesis, the growth cells acquire the capacity for embryogenesis under conditions of cellular stress. Sucrose is the predominant sugar in plants for energy production and facilitates vital functions. Sucrose is converted to glucose and glucose. Sucrose is the most common source of carbohydrates used in plant tissue culture.

    Materials and Methods

     The present study was performed in the tissue culture laboratory of the horticulture department of Gorgan University of Agricultural Sciences and Natural Resources in 1399 and 1400. Native Iranian asparagus seeds with octaploid ploidy level were used in this experiment. B5 medium containing 2, 4-D with a concentration of 2 mg /l was used to induce the embryo. Concentrations of 3, 6, 9, 12 and 15% in liquid medium were used to evaluate the effect of sucrose. The pH of the culture media were adjusted to 5.7. After the induction phase, the samples entered the realization phase and the subculture were cultured in the previous environments but with the aim of emerging the embryos (realization phase) while the hormone was removed from them. After 4 weeks in the embryonic development stage, the number of globular and bipolar embryos was observed using a computer-connected stereoscope at 20 and 40 micron magnifications.

    Results and Discussion

    The results obtained from this study showed that there is a significant difference between different concentrations of sucrose in terms of embryogenesis formation at different stages of embryogenesis. According to the presented results, change in sucrose concentration caused a change in the formation of embryos and the highest number of spherical embryos was observed with a significant difference (p <0.001) in 9% sucrose concentration. According to the comparison results, the concentration of 9% sucrose showed the highest amount of bipolar embryo among other different concentrations. Statistical results of photosynthetic pigments and anthocyanins showed that there was a significant difference between different concentrations of sucrose. As shown in Figures 2 and 3, the highest levels of chlorophyll a, b, total and carotenoids were observed at a concentration of 9% sucrose and the lowest amount of chlorophyll a at concentration of 12% and total chlorophyll and carotenoids at concentration of 3%. Also, the results obtained from regression analysis showed that the highest amount of photosynthetic pigments and starch was observed in 9% sucrose concentration. Finally, in this study, it was found that the best concentration affecting the vegetative embryogenesis of octaploid asparagus is 9% sucrose. 

    Conclusion

     Carbohydrates are the main constituents of the plant and are most used in tissue culture medium, especially sucrose for growth and differentiation. It is noteworthy that high concentrations of sucrose are not only nutritional but also change the osmotic pressure in the culture medium. The relationship between glucose status and embryonic formation has been proven. In the meantime, the capacity of sucrose to support embryonic growth is greater, so that increasing sugars such as sucrose increase the potential for embryogenesis. According to the results of the present study, 9% sucrose in B5 culture medium showed an important role in chlorophyll production and caused photosynthesis and carbohydrate metabolism in this medium to increase, and as a result, the amount of sugar and its accumulation in culture explants. Increased in this medium and eventually caused the emergence of embryos with photosynthetic pigments in the resulting seedlings. Increasing the level of sucrose also prevents rapid germination and helps the development of the root system.

    Keywords: 4-D, Carbohydrate, embryogenesis, Photosynthetic pigments
  • M. Jafari, A.A. Shokouhian *, E. Chamani, A. Ghavedal Pages 843-855
    Introduction

     Iron has a significant effect on the quantity and quality of agriculture products. Factors affecting the absorption of this element increase its efficiency. Meanwhile, the pH of the nutrient solution plays an important role in the absorption of iron. Iron is one of the essential elements for plant growth and plays an essential role in chloroplasts. Due to iron deficiency, the activity of several enzymes such as catalase, cytochrome and oxidase and ferroxin is significantly reduced. The amount of iron in the soil is high, but plants only absorb two-capacity of soluble soil, which is negligible compared to the total iron. Soil environmental conditions affect the amount of iron by the plant, so it is difficult to control the uptake of iron by the plant. It has the highest ability to absorb iron and manganese at pH less than 6. For this reason, acetic acid was used to stabilize the pH of the solution. Acetic Acid is a polar solvent and an organic compound. The use of inexpensive organic acid and citric acid in agriculture, despite its positive effects on calcareous soils and their reasonable price is still not common in Iran. Acetic acid has a carboxylic group and therefore has all the properties of an acid.

    Materials and methods

     This experiment was carried out in the form of double split-split plot in a completely randomized block design on a strawberry plant of diamant cultivar in the research station of Mohaghegh Ardabili University during the years 2015- 2017. Factors included Acetic Acid (0, 1, 2 and %3), iron in two levels (Sequestrin 25gr and Nano 1gr) along with two levels of agricultural soap agents (0 and % 7/5) as foliar spraying. Foliar application of pH nutrient solution from the three-leaf stage of plant (mid-April) to the end of May a total of five times 10 days apart in both years. Two weeks after the last foliar application (June of the second year) plant growth indices including, total chlorophyll, number of fruits per plant, fruit pH, total acidity, soluble solids, fruit volume, fruit fresh weight, fruit dry weight, and leaf iron content and fruit yield per plant was measured.

    Result

     The results of this study showed that the three-way interaction of foliar application of Acetic Acid with iron with agricultural Soap on the average concentration of leaf iron and number of fruits at the probability level was %5 and in total chlorophyll at the %1 probability level was significant, the best result in the mentioned traits was the combination of treatment of Acetic Acid %2 with Sequestrin iron with soap Moyan (%7/5). The interaction effect of Acetic Acid and iron type on traits of fruit pH, fruit volume, fruit fresh and dry weight at %5 probability level and in yield at %1 probability level were significant. Fruit volume, fruit fresh weight and fruit dry weight and yield showed the best results due to treatment combination of %2 Acetic Acid with Sequestrin iron fertilizer. But for fruit pH trait, the best results were related to the treatment of Acetic Acid %3 on the leave of Sequestrin iron. The Interaction of the iron and agricultural Soap was significant on the amount of soluble solids at %5 probability level and the total acidity strawberries fruit was significant at %1 probability level. In the case of soluble soild and Acidity, Sequestrin iron treatment and agricultural soap had the best results. According to the results of this study, the combination %2 Acetic Acid with of iron fertilizer Sequesterin in combination with agricultural soap Moyan (%7/5) due to the reduction in leaf area tensions improves the obsorption of iron and the quantitative and quality characteristics strawberries.

    Conclusion

     Based on the findings of this research, it can be concluded that Acetic acid %2, has better result on the absorption of iron fertilizer, along with agricultural soap (% 7/5) application than other treatments and qualitative traits of strawberry fruit. In treatment %2 Acetic acid most measured traits such as total chlorophyll, leaf iron, fresh weight, fruit dry weight and yield has shown a significant increase. Acetic acid by reducing the pH of the cell sauce and increasing the activity of the reductase enzyme increase the iron solubility and easily provides the iron to the plant. Due to the pH alkalinity of most soils in Iran, the use of Acetic acid in iron nutrient solution on the absorption of iron Sequestrin in combination with % 7/5 of agricultural soap due to having a hydrophilic head and a hydrophobic with %40 to %50 increase in effective of foliar fertilizers. As a result, with more absorption it can be an advanced approach to better absorption of iron by plant and increase the quantity and quality in the product.

    Keywords: Chlorophyll, vitamin C, yield
  • M. Moradi *, H. Nastari Nasrabadi, K. Ghasemi Bezdi Pages 857-867
    Introduction

     The Genus Thymus is one of the most important genera of the Lamiaceae family. According to Jalas (1971), Thymus is divided into eight sections: Micantes, Mastichina, Piperella, Teucrioides, Pseudothymbra, Thymus, Hyphodromi, and Serpyllum. About 18 species exist in some areas of Iran and most of them belong to Serpyllum Section and kotschiani Subsection. Chromosomal information is an important key for taxonomy, phylogeny, evolution, genetics and breeding in thyme. Therefore, this work was carried out to study the cytogenetic characteristics of genus Thymus belonging to the Subsection Kotschyani for breeding purposes and taxonomy.

    Materials and Methods

    Seeds were collected from 5 wild populations and germinated on wet filter paper at 20 oC. One cm long roots were pretreated with 8-hydroxyquinolin and then washed in distilled water and fixed in carnoy solution for 24 hours. Hydrochloric acid (1N) was applied for 7 min to hydrolyze the roots. Staining was done by orcein for 24 h at room temperature. Stained roots squashed in one drop of 45% acetic acid and examined by a ZEISS Axiophot compound microscope. Cells in metaphase stage were photographed with a D450; Canon Inc. Japan digital camera. Ten well prepared metaphasic cells were selected and some chromosomal characteristics such as total chromosomal length (TL), long arm length (L), short arm length (S), the arm ratio (AR) [LA/SA], and centromeric index (CI), were measured using Micro Measure ver. 3.3 software. The following karyological parameters were determined: total chromosome form (TF%), intrachromosomal asymmetry index (A1) and interchromosomal asymmetry index (A2). Karyotypic characteristics have been determined using the symmetry classes of Stebbins (SC). Karyotype formula was determined from chromosome morphology based on centromere position in accordance with the classification of Levan.

    Results and Discussion

     This study reports the chromosome number and meiotic behavior of 31 populations belonging to 8 species of Thymus Subsect. kotschyani from Iran. In most species of this subsection, the base number of chromosome x = 15 and two diploid and tetraploid ploidy levels with chromosome number of 2n = 30 and 60 were observed. Only in T. migricus species, the base number of chromosome x = 14 was reported with two levels of diploid and tetraploid ploidy and chromosome numbers of 2n= 28 and 56. The chromosomes were mostly metacentric (m) or sub-metacentric (sm) in all species Among the various species with basic number of x= 15, the highest percentage of TF and the lowest amount of A1 were observed in populations belonging to T. eriocalyx (T7) indicating that this species has the most symmetric karyotypes. The lowest percentage of TF and the highest amount of A1 are in population of T. lancifolious (27) and T. fedtschenkoi (T28) species; this shows that the species has the most asymmetric karyotype among the species of this subsection. The highest amount of A2 was observed in T. eriocalyx (T7) species, indicated the asymmetry between chromosomes and chromosomal length. The difference in the number of chromosomes, ploidy levels and karyotype asymmetry in the populations and different species may be related to different environmental conditions in their habitat, pollination system (cross pollination) or polyploidy (Aneuploidy) in this genus.

    Conclusion

     The results showed that basic chromosome number in most species is 15 (x= 15). Two ploidy levels (diploid and tetraploid) were observed among different species. Chromosomes in most species, were metacentric and sub-metacentric. Based on intra- chromosomal symmetry (A1 and TF) T. eriocalyx species (T7) has the most symmetric and most primitive karyotype and the species T. lancifolius (T27) and T. fedtschenkoi (T28) have the most complete and the most asymmetric karyotypes. Also based on inter- chromosomal symmetry, (A2) T. eriocalyx (T) species has the most asymmetric karyotype.

    Keywords: Cytogenetic, Karyotype, Subsec. Kotschyani, taxonomy, Thymus spp
  • H. Zakeri, Z. Roudbari * Pages 869-883
    Introduction

        Silicon (Si) is not an essential element for the growth of plants, but its role in improving the yield by reducing the environmental stresses and crop durability is very important. Despite the abundance of Si in the soil, the amount of dissolved Si available for herbal absorption might be limited. Therefore, using this useful element through foliar application can be effective in the growth of the plants such as eggplant. On the other hand, profitability is dependent on the high yield and quality per unit area in producing greenhouse vegetables.

    Materials and Methods

        To study the effect of foliar application of Si fertilizer from the source of Khazra Chelated Silicon (commercial brand, contains 2% chelated silicon for plant at pH 3 to 11 and no silicate in the form of salt) in different stages of the growth of eggplant and bush pruning in hybrid eggplant, a greenhouse experiment was conducted in a soil environment as a split-plot in a randomized complete block design with 3 replications in Minab region. In this experiment, the consumption of Si fertilizer as the main factor at 4 levels (0 and 2 per thousand in the vegetative phase, 2 per thousand in the reproductive phase and 2 per thousand at the two vegetative and reproductive phases) and the type of pruning as a sub-factor in 4 levels (two-branch training system, three-branch training system, four-branch training system and no training system) were applied. Eggplant seeds were transplanted in an environment containing sphagnum in November and then at four-leaf stage they were transferred to the main field in December. The distance between the rows was one meter and the distance between the plants in the row was 45 cm. After positioning the plant in the greenhouse and reaching the appropriate growth, pruning and foliar application of Si fertilizer began and in the treatment without fertilizer, spraying with pure water was used. Silicon fertilizer was sprayed on the eggplant leaves according to the instructions recommended by the manufacturer every eight days.  Once the eggplants reached a suitable reproductive growth and started fruiting, fruit thickness, fruit length, the weight of each fruit, the number of the fruits on each plant, and finally the yield of each plant were recorded in each pick. To evaluate the effect of Si on the durability of eggplant after picking, 3 fruits harvested from each treatment were first weighed by a digital scale, and then kept at room temperature for 2 weeks and after two weeks, the weight of each fruit was measured again. Based on two recorded weights, the percentage of fruit weight loss was calculated. Furthermore, to evaluate the effect of silicon fertilizer and plant pruning on resistance to fungal diseases, scores, from 1 to 9, were given to the plants in each treatment. Plants without any fungal infection were assigned a score of 1, and completely infected plants were assigned a score of 9.

    Results and Discussion

        The results showed that pruning improved the fruit length, the plant height, the fruit weight in each plant, and the plant yield and reduced the percentage of fungal infection in the plant. Moreover, the silicon foliar application positively affected the number of the fruits in each plant and increased the durability of fruits after harvesting. Silicon foliar application in the two vegetative and reproductive stages together and plant pruning in a four-branch way resulted in maximum plant yield, improved crop quality, and improved greenhouse management. The intensity of fungal infection was affected by different levels of silicon, plant pruning, and the interaction of the two factors at a probability level of five percent. Comparison of interaction averages showed that pruning and foliar application in vegetative and reproductive stages together significantly reduced fungal infection in the greenhouse. The highest intensity of fungal infection was related to plants without pruning and lack of silicon. Pruning improves airflow and modulates humidity in the plant canopy and as a result eliminates the proper conditions for fungal growth. Silicon also prevents fungal penetration into plant cells by depositing in the plant cell wall and strengthening plant tissue, and as a result inhibits fungal growth in the plant. Marschner (2012) reported that silicon would increase resistance to fungal and bacterial diseases and pests. Plant diseases are a major threat to agricultural production because they cause a serious loss of yield and quality of the crop. Numerous studies have reported that Si is effective in controlling diseases caused by fungal and bacterial pathogens in various plant species. Furthermore, given that one of the challenges for producers to deliver high-quality crops to the target market is their durability after harvesting, it seems that silicon foliar application at the two vegetative and reproductive stages might be effective to overcome such a challenge. Choosing a training system depends to a large extent on the ease of work in the greenhouse, the production system, and the superiority of the production rate. On the other hand, a significant increase in yield and crop quality was reported for barley, rice, sugarcane, tomato, cucumber, soybean, and bamboo due to Si consumption during the growth. Another important feature of silicon is that it increases plant damage under biological and non-biological stress conditions as well as resistance against stress.

    Conclusion

        According to the results, four-branch training system of eggplant and also silicon foliar application in the two vegetative and reproductive phases of greenhouse eggplant improved the yield components and increased the durability after harvesting. Pruning the plant into four branches also improved yields. Therefore, using silicon with four-branch training system is recommended, especially in traditional greenhouses without proper ventilation systems.

    Keywords: Branch pruning, Greenhouse vegetables, Post-harvest shelf life, useful elements
  • M. Ghafouri, F. Razavi *, M. Arghavani, E. Abedi Gheslaghi Pages 885-901
    Introduction

     Nowadays, the application of chemical compounds is limited due to their harmful effects on human and the environment health. The benefits of seaweeds as sources of organic matter and fertilizer nutrients have been known to agriculture for centuries, especially in coastal areas extracts of these seaweeds have been used for decades as foliar- and soil-applied treatments in crop production systems due to the presence of a number of plant growth-stimulating compounds. Unlike chemical fertilizers, extracts derived from seaweeds are biodegradable, non-toxic and non-hazardous to humans, animals and birds. Therefore, it is required to find a safe compound that is utilized in the postharvest technology of fruit and vegetables. Pre-harvest application of nutrient solutions such as seaweed increases the quality and quantity of crop and also enhance their storage life and marketability. Various researchers reported that aqueous extracts of seaweed increased the yield and quality of tangerine and orange, strawberry, grape, apple, and watermelon fruit. Thus, the aim of the current study was to investigate the effect of pre-harvest foliar application of Seaweed extract on quality and quantity values, antioxidant properties, and storage life of kiwifruits.

    Material and Methods

     This experiment was carried out on 10-year-old kiwifruit vines, in a commercial orchard located in Gilan Province. Vines were selected with uniform size in terms of growth, yield and fruit load, then sprayed with seaweed extract at four levels of 0, 1, 2 and 3 g.l-1 as a foliar spray and control vines only received water. Foliar spraying was performed in three stages, (110, 125 and 140 days after full bloom stage) and Tween 20 was used as a surfactant. This experiment was designed as factorial based on randomized complete block design with three replications. The fruits were harvested in November with soluble solids content (TSS) of 6.5-6.2% and then transferred to the post-harvest physiology laboratory of the University of Zanjan. The treated fruits were stored for 90 days at 1 ° C with 90% RH. Sampling was done at harvest time and after 30, 60 and 90 days of storage and some quantity and quality traits such as weight loss, tissue firmness, TSS, ascorbic acid, total phenol and flavonoids, antioxidant capacity and the activity of superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL) enzymes were evaluated.

    Results and Discussion

     The ANOVA results showed that seaweed extract, storage time, and interaction of seaweed extract × storage time had a significant effect (p≤0.01) on evaluated traits. All treatments maintained the antioxidant capacity, total phenol and flavonoids content and PAL activity at a higher level compared with control. The amount of fruit tissue firmness, TA and ascorbic acid decreased by increasing the storage time, and at the third month of storage, the lowest amount was observed in the control fruit. Also, comparing the interaction of the mean of treatments and storage time showed that pH, weight loss, TA, TSS, antioxidant capacity, total phenol, flavonoids and PAL enzyme activity increased by increasing the storage time. At the end of the storage time, the highest level of TSS, weight loss and pH were observed in the control fruit. The lowest antioxidant capacity (48.14 %) was observed in the control treatment at harvest time and the highest antioxidant capacity was observed in 3 levels of brown algae extract treatment at the end of storage period. Comparison of means showed that at the first 30 days of storage, the highest PAL enzyme activity was observed in the treatment of 3 g / l of brown algae. PAL enzyme activity significantly increased after the experiment. At the end of storage period, the lowest PAL enzyme activity was observed in control fruit. Treatment of 3 g / l brown algae had higher PAL activity. PAL, as a key enzyme in phenylpropanoid metabolism, catalyzes the conversion of phenylalanine to trans-cinnamic acid, which is the first step in the biosynthesis of phenylpropanoids and leads to the production of secondary metabolites such as lignin, phytolaxoids, and flavonoids. The direct and positive relationship of this enzyme with the synthesis of phenols and flavonoids has been discovered in the fruits of blood orange, strawberry and blueberry. The results of the comparison of the mean showed that the total phenol and flavonoids increased by increasing the storage time. The lowest phenol (23 mg GAE.100 g-1 FW) was observed in control fruit at harvest and the highest (8.88 mg GAE.100 g-1 FW) content of total phenol was observed in 3 levels of brown algae extract at the third month of storage. Plants release phenolic compounds in response to some messenger compounds that play an important defense role. Studies show that there is a positive relationship between total phenol content and their antioxidant activity. Flavonoids are also polyphenolic compounds and are the most important secondary compounds of plants. Under oxidative stress, in plants, the activity of propanoid pathway increases, especially the pathway of flavonoids biosynthesis. Flavonoid compounds are abundant in plants and show antioxidant activity. Seaweed extract enhances the antioxidant capacity of the fruit and thereby inhibits oxygen-free radicals Treatment of 3 g/l seaweed extract had the best effect among the treatments applied in maintaining firmness, fruit weight loss, TA, antioxidant capacity, total phenol and flavonoids and PAL enzyme activity. All three levels of seaweed extract increased the amount of total phenol, flavonoids and antioxidant capacity all over the storage time, but no significant difference was observed among the treatments levels. Based on the results, the application of 3 g/l seaweed extract effectively increased the antioxidant capacity and PAL enzyme activity during 90 days of storage time. As a result, seaweed extract treatment had positive effects on maintaining the quality and increasing the shelf life of kiwifruit during 90 days of storage.

    Conclusion

    Seaweed extract is one of the natural compounds and compatible with human health and nature has medicinal and nutritional value that can increase the shelf life and maintain fruit quality in the postharvest period. In summary, foliar application of seaweed extract has a significant effect on fruit firmness, total soluble solids, total acid, vitamin C, phenol and total flavonoids, total antioxidant activity and the enzyme phenylalanine ammonialyase. The appropriate treatment for kiwifruit cultivar ‘Hayward’ is introduced. Among the applied treatments, 3 g/l of seaweed extract had the best effect on firmness (40.40%), fruit weight loss percentage (41.87%), titratable acid (25.37%), vitamin C (33.26%), antioxidant capacity (26.70%), total phenol (81.17%), total flavonoids (103.67%) and PAL enzyme activity (153.75%) compared to the control in 90 days of storage.

    Keywords: antioxidant capacity, Foliar spraying, phenylalanine ammonia-lyase enzyme, total phenol, flavonoids
  • M. Osku, A. Khandan Mirkohi *, R. Naderi Pages 903-915
    Introduction

     The genus Chlorophytum (also known as spider plant) which is mainly cultivated as an ornamental plant for its slash and colored leaves, specifically distributed in the pantropic regions. It is a perennial rhizomatous plant with often short and indistinct rhizomes, while with thicker or slightly fleshy roots. The roots of these species are considered as one of the important phytochemical components. the use of Chlorophytum comosum as a contaminant accumulator has already been documented in the literature.This plant is a soil conditioner and can absorb lead, cadmium, Se and As while its leaves accumulate mercury. It is also able to absorb toxic organic pollutants such as formaldehyde and benzene and is also able to retain CO2. Leaf surface morphology has been shown to affect the ability of a particular plant to retain contaminants. Chlorophytum comosum introduced as a plant that requires high nitrogen. Nitrogen is an essential macro element for the growth and development of plants which involved in many physiological reactions and it is one of the elements that plants need in all their activities. The effect of N form on plant growth depends on plant species and nitrogen level of the soil. Plants absorb both ammonium (NH4+) and nitrate (NO3-) from soil solution, and these two mineral forms are their most important sources of nitrogen to supply the plant demand. Absorption of ammonium by plants requires less energy than absorption of nitrate. It seems that most plants have the best performance in a certain ratio of nitrate to ammonium (NO3-/NH4+ ratio). This ratio seems to regulate the distribution of absorbed nitrogen between the branches and roots. It may also vary between species. The optimal ratio may also depend on the environmental conditions such as pH, light intensity, and root zone temperature. This study was performed to determine the effect of different levels of ammonium nitrate on growth, yield factors and ornamental aspects of the spider plant as a desired ornamental product. The use of ammonium nitrate to meet the houseplants demand considering the supply of both types of nitrogen sources, increases the yield and quality of these plant. However, despite the importance of the nitrogen in the performance of this ornamental plant (Chlorophytum comosum), the desired amount of nitrogen for its growth and quality has not yet been reported. Therefore, the present study was conducted to investigate the effect of different levels of ammonium nitrate on the growth and physiological characteristics of spider plant to find the best level of application of ammonium nitrate fertilizer as an easily available source to increase the growth and visual quality of this plant.

    Materials and Methods

     This research was conducted based on randomized complete block design (RCBD) with four treatments and three replications.  Treatments include four levels of ammonium nitrate of 100 (control), 200, 400, 600 mg-1 kg of soil. Treatments applied first at the substrate preparation process and then was applied in the one third depth of each pot, monthly. Desired factors such as morphological characteristics (plant height, leaf number, stolon number, fresh weight, dry weight, root fresh weight, root dry weight, root volume, root depth, root length, pot weight, leaf area) and physiological characteristics (total chlorophyll, total protein, texture nitrate and proline) were evaluated. Also soil analysis was performed before starting of the experiment. Statistical analyses of the data for examined traits were performed using SAS software and comparisons of means using Duncan's multiple range test, at 5% probability level.

    Result and Discussion

     The results indicated that the application of ammonium nitrate fertilizer significantly improved most of the studied traits. Supplying ammonium nitrate fertilizer at desired level meet the nitrogen demand of Spider plant during the growth and improved production of biomass. The plant height, leaf number, fresh weight, dry weight, root fresh weight, root dry weight, and leaf area were increased by increasing ammonium nitrate level. Nitrogen fertilizers play an important role for increasing plant yield by expanding shoots and producing sufficient carbohydrates. In addition to plant growth, they also affect plant morphology. Maximum amount of protein, nitrate of tissue and total chlorophyll observed in 400 mg-1kg of ammonium nitrate level. Nitrogen is one of the essential elements that plays an important role in the production of chlorophyll and protein, therefore the use of nitrogen fertilizers leads to synthesis of chlorophyll and protein at higher level. The highest amount of proline (11.20 μg-1 mL) was measured at 600 mg-1kg of ammonium nitrate level and the lowest (3.57 μg-1 mL) in the control, because with high consumption of nitrate, the plant needs more water and nitrogen is a structural component of proline. Accumulation of proline helps the plant to survive and recover after drought stress.

    Conclusion

     According to the results of our experiment, application of nitrogen fertilizer had a positive effect on growth, and consequently led to increase the plant vegetative yield. Treatment of 400 mg-1kg of ammonium nitrate level increased growth and yield factors and the ornamental aspect of Spider plant as a desired ornamental crop. Application of 400 mg-1kg of ammonium nitrate level are recommended to access an acceptable quantitative and qualitative yield in this plant.

    Keywords: Chlorophyll, Growth traits, Protein, yield
  • M. Piri, Z. Jabbarzadeh * Pages 917-936
    Introduction

     Lisianthus (Eustoma grandiflorum) from Gentianaceae family is from wild flowers of north and west America. Lisianthus, a relatively new floral crop to the international market, quickly ranked in the top ten cut flowers worldwide due to its rose-like and blue flowers. It is also widely used as a flowering potted and bedding plant. Lisianthus ‘Mariachi Blue’ is cultivated as a cut flower. Salicylates have very beneficial effects on plant growth and development. The effect of phenolic compounds in many biochemical and physiological processes including photosynthesis, ion adsorption, membrane permeability, enzyme activity, flowering, stimulation of plant resistance systems, heat production and plant development has been proven. The most famous member of this group is salicylic acid, which as a simple phenolic compound, is naturally produced by plants. Salicylic acid (SA) is considered to be plant signal molecule that plays a key role in plant growth, development, and defense responses. Polyamines (PAs) are ubiquitous and biogenic amines that have been implicated in cellular functions in living organisms. In plants they have been implicated in a wide range of biological processes including cell division, cell elongation, senescence, embryogenesis, root formation, floral initiation and development, fruit development and ripening, pollen tube growth and plant responses to biotic and abiotic stress. Sodium nitroprusside is a nitric oxide releasing agent. Nitric oxide is a gaseous free radical that can disperse very rapidly through cell membranes due to its gaseous nature and medium shelf life, without a carrier. Nitric oxide (NO) is an unstable environmentally-friendly gas radical that is used to protect the postharvest longevity of different horticultural crops. In addition to controlling harvested crop senescence, NO is involved in many plant processes, e.g., germination, growth and development, photosynthesis, pigment synthesis, defensive system, and many others. In the present study, we investigated the effects of foliar application of salicylic acid, spermidine and sodium nitroprusside on some morpho-physiological characteristics and vase life of lisianthus flowers ‘Mariachi Blue’.

    Materials and Methods

     This study was conducted based on a completely randomized design with 10 treatments, 4 replications which each replication containing 2 pots. The treatments were included spermidine at concentrations of 0.5, 1 and 2 mM, salicylic acid at concentrations of 0.5, 1 and 1.5 mM, sodium nitroprusside at concentrations of 50, 100 and 200 μM and control (without any application of growth regulators) as foliar application at intervals of 15 days for 2 months. Plant characteristics including leaf area, stem length, fresh and dry weight of leaves and flower, number of buds, flowers’ length and diameter, photosynthetic pigments and vase life were assayed. To perform analysis of variance and compare the mean of the studied traits, SAS software version 9.1 was used. The means were compared using the Tukey multi-domain method at a probability level of 1%. Also, Excel (2016) software was used to draw the chart. 

    Results and Discussion

     The results obtained from analysis of variance in this study showed that the effect of growth regulators used in the study was significant at the level of 1% probability on all morphological traits measured, photosynthetic pigments and vase life of lisianthus flowers. Mean comparison graphs showed that salicylic acid, spermidine and sodium nitroprusside had a positive effect on some morphological traits, photosynthetic pigments and vase life compared to control. It can be concluded that, salicylic acid caused to increase all parameters except the flowers’ fresh weight compared to control. Spermidine increase stem length, leaf fresh weight, flowers’ fresh and dry weight, length, and diameter, chlorophyll index, chlorophyll b, and carotenoid and vase life of flowers. Also, sodium nitroprusside had beneficial effects on all parameters in this research except leaf area, leaf dry weight, chlorophyll a and vase life of flowers. Salicylic acid plays an important role in regulating some physiological processes of plants such as growth and development, ion uptake and transport, stomatal conductivity, and membrane permeability, which is effective in plant photosynthesis and with increasing photosynthesis, plant growth rate increases. Polyamines such as spermidine are involved in a wide range of developmental stages including cell division, embryogenesis, root growth, and flowering. Sodium nitroprusside is involved in the most important plant processes such as photosynthesis, respiration, growth and cell division. Probably, these growth regulators, due to their effect on plant growth, flowering, as well as photosynthetic pigments, have caused the increment of plant biomass and vase life.

    Conclusion

     In the present study, the effect of salicylic acid, spermidine and sodium nitroprusside on some growth and flowering characteristics, photosynthetic pigment and vase life of Eustoma grandiflorum ‘Mariachi Blue’ was assayed. According to the results of the present study, it can be concluded that these growth regulators improved growth indices, flowering parameters, photosynthetic pigment and vase life of flowers. According to the results, the appropriate concentrations for salicylic acid were 1 mM, for spermidine, 1 mM and for sodium nitroprusside were also 50 and 100 μM.

    Keywords: Chlorophyll content, Flower diameter, Growth regulator, Nitric oxide, Polyamine
  • M. Karimi *, F. Salimi, A. Pakdin Parizi Pages 937-948
    Introduction

     Plant size control is one of the most important factors in the production of ornamental plants. Plant size can be limited by a variety of methods, including genetic control, environmental conditions, and the use of plant growth retardants. Lily (Lilium sp.) is one of the most important cut flowers with different species and cultivars. Some lilies can grow up to one meter in height. Usually the appropriate height of the stem for pot use is 40-30 cm, which is achieved by using growth regulators. This study aimed to investigate the role of uniconazole and cycocel to control height, quantitative and qualitative characteristics of Lilium.

    Materials and Methods

     This study was carried out in a factorial experiment based on completely randomized design. Uniconazole (0, 5 and 10 mg L-1) and cycocel (0, 1000 and 1500 mg L-1) were the first factor and application methods of the above compounds (immersion application and foliar application) was the second factor. Disease-free bulbs (with a circumference of 15 cm) Lily (Longifiorum × Asistic cv. Eyeliner) was purchased from Saei Gol Company in Tehran. To apply the immersion treatment, the bulbs were immersed in a solution of cycocel (CCC) and uniconazole (UN) for 7 minutes before planting. Then they were planted in plastic pots. In foliar spraying treatments, the bulbs were first planted in pots and when the stem height reached 10 cm, they were sprayed with CCC and UN. Water was used for control treatment. Leaf number, plant height, total chlorophyll, total phenol, flower diameter, enzyme activity (PPO, GPX or CAT) and time of budding were measured. Analysis of variance was performed using SAS software and mean comparisons were analyzed by the least significant difference test.

    Results and Discussion

     The effect of growth retardant, the application method and their interaction was significant on stem height. The shortest plants were observed in foliage application of 10 mg L-1 UN which was not significantly different from the concentration of 10 mg L-1 UN in immersion method. The mechanism of growth retardants is to inhibit the biosynthesis of gibberellins. Therefore, they act as anti-gibberellins to reduce plant height. Uniconazole inhibits the biosynthesis of gibberellins by blocking kaurene oxidase, a P450 enzyme. The largest diameter of lily flowers was observed in immersion application of 1500 mg L-1 CCC however, there was no significant difference between flower diameter of mentioned treatment with immersion method of 1000 mg L-1 CCC and foliar application of 10 mg L-1 UN. Growth retardants increase endogenous cytokinin levels, resulting in increased cell division and improved flower growth and flower diameter. The effect of growth retardant on number of leaves was significant. The highest numbers of leaves were observed in 1000 and 1500 mg L-1 CCC. The effect of growth retardant, the application method and their interaction was significant on chlorophyll and phenol contents. The highest chlorophyll content was observed in immersion application of 10 mg L-1 UN. Growth retardants appear to increase chlorophyll content due to increased cytokines. The results of this study showed an increase in total phenol in plants treated with uniconazole 10 mg L-1. Growth retardants have been reported to increase phenol content by increasing plant resistance to environmental stresses. Catalase enzyme activity was significantly affected by growth retardant. The highest activity of CAT enzyme was related to CCC at 1500 mg L-1. The effect of growth retardant and their interaction was significant on GPX enzyme activity. The highest enzyme activity was obtained in plants sprayed with 1000 mg L-1 CCC. Growth retardants have been reported to increase enzyme activity, causing plant resistance to environmental stresses and delaying lipid peroxidation and membrane degradation.

    Conclusion

     Considering that one of the most important goals in the present study was the production of dwarf lilium, it can be said that uniconazole 10 mg L-1 (foliar application and immersion) had a significant effect in controlling stem height compared to other treatments. The effect of this treatment on other traits such as flower diameter, total chlorophyll and total phenol was also significant. The time of budding, leaf number and activity of CAT and GPX enzymes was better in cycocel treatment with a concentration of 1500 mg L-1. Therefore, the use of uniconazole can be recommended for the production of dwarf plants, considering that it works better in two important traits, including controlling stem height and increasing flower diameter. It is also suggested that since the cycocel treatment was effective in increasing enzymatic activity, the effect of this treatment on plant resistance to environmental stresses should be investigated.

    Keywords: Chlorophyll, Enzyme Activity, Flowering, Growth inhibitors, Plant height