تغییرات ویژگی‌های مورفوفیزیولوژی و عملکرد اسانس برگ و گل سرخارگل (Echinacea purpurea (L.) Moench) با کاربرد برگی سدیم نیتروپروساید (SNP) تحت تنش خشکی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی سابق کارشناسی ارشد، گروه علوم باغبانی، دانشگاه آزاد اسلامی واحد علوم و تحقیقات، تهران، ایران

2 استادیار، بخش تحقیقات گیاهان دارویی، مؤسسه تحقیقات جنگل‌ها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران

چکیده

تنش خشکی یکی از محدود کننده‌ترین عوامل محیطی در رشد و تولید گیاهان محسوب می‌شود. سدیم نیتروپروساید (SNP) به­عنوان یک تولیدکننده نیتریک‌اکساید (NO) در کاهش تنش اکسیداتیو ناشی از تنش‌های غیرزیستی نقش دارد. به­منظور بررسی اثر محلول‌‌پاشی SNP بر رشد، عملکرد و برخی ویژگی‌های بیوشیمیایی گیاه دارویی سرخارگل در شرایط تنش خشکی، آزمایشی در قالب طرح کرت‌های خردشده در پایه بلوک‌های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی مؤسسه تحقیقات جنگل‌ها و مراتع کشور-کرج در سال­های زراعی 95-1394 طراحی و اجرا شد. تیمارهای آزمایش شامل دو عامل SNP در چهار سطح (صفر، 100، 200 و 400 میکرومولار) و تنش خشکی در سه سطح ]30 (شدید)، 60 (متوسط) و 90 (شاهد) درصد ظرفیت زراعی[ بود. در مرحله گلدهی کامل گیاه، ارتفاع بوته، تعداد شاخه جانبی، برگ و گل، ماده خشک اندام‌های هوایی گیاه و نیز بازده اسانس برگ و گل اندازه‌گیری شد. ­همچنین، نمونه‌گیری از برگ‌ها برای اندازه‌گیری محتوای نسبی آب (RWC) و کلروفیل، فعالیت آنزیم‌های آنتی‌اکسیدانی سوپر‌اکسید ‌دیسموتاز (SOD) و پراکسیداز (POD)، محتوی مالون‌دی‌آلدهید (MDA)، پرولین و فنل کل هم انجام شد. بر اساس نتایج آزمایش، بیشترین مقدار صفات مورفولوژیک اندازه‌گیری­شده و وزن خشک شاخساره مربوط به محلول‌پاشی SNP ‌با غلظت ۲۰۰ میکرومولار تحت شرایط عدم تنش خشکی (شاهد) بود. بیشترین مقدار RWC با میانگین 9/78 درصد در رطوبت 90 درصد ظرفیت زراعی (شاهد) و سطح 200 میکرومولار SNP به‌دست آمد. هم‌چنین غلظت‌های بالاتر SNP مصرفی (200 و 400 میکرومولار) در تنش متوسط (60 درصد ظرفیت زراعی)، توانست با افزایش فعالیت آنزیم‌های SOD و POD و کاهش محتوی MDA موجب تحمل تنش خشکی شود. بیشترین مقدار پرولین (7/16 میکرومول بر گرم وزن تر) و فنل کل (4/127 میلی‌گرم گالیک­اسید بر گرم ماده خشک) هم مربوط به غلظت 400 میکرومولار SNP بود. در مجموع می‌توان گفت که کاربرد SNP در غلظت‌های بالاتر، تحت شرایط تنش خشکی، ضمن ­اینکه می‌تواند موجب تعدیل خسارت تنش شود، افزایش ترکیبات مؤثره گیاه را نیز می‌تواند در پی داشته باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Changes in morpho-physiological characteristics and the leaf and flower essential oils yeild of coneflower [Echinacea purpurea (L.) Moench] with sodium nitroprusside (SNP) foliar application under drought stress

نویسندگان [English]

  • Shaghayegh Mousavi 1
  • Samaneh Asadi-Sanam 2
  • Maryam Pezhmanmehr 1
1 Former M. Sc. Student, Department of Horticulture Science, Faculty of Agriculture and Natural Resources, Islamic Azad University, Tehran, Iran
2 Assistant Professor, Department of Medicinal Plants, Research Institute of Forests and Rangelands, AREEO, Tehran, Iran
چکیده [English]

Drought stress (water scarcity) is one of the most limiting environmental factors in plant growth and production. Sodium nitroprusside (SNP) as a nitric oxide doner compound (NO) plays an important role in reducing the oxidative stress caused by abiotic stresses. In order to investigate the effect of SNP foliar application on some biochemical characteristics, growth and yield of Echinacea purpurea Moench L. under drought conditions, an experiment was conducted in a split plot design in a completely randomized block design with three replications at the Research Institute of Agriculture, Institute of Forest and Rangelands, Karaj, Iran, in 2015-2016. The experimental treatments included SNP factor at four levels (0, 100, 200 and 400 µM) and drought stress factor at three levels [30% field capacity (severe), 60% field capacity (moderate), 90% field capacity (control)]. At full flowering stage, plant height, number of lateral branches, leaf and flower number, dry weight of shoots and percentage and yield of shoot essential oil were measured. Also, leaves sampling was performed to measure relative water content (RWC), chlorophyll content, the activity of superoxide dismutase (SOD) and peroxidase (POD) enzymes, malondialdehyde (MDA), total phenol and proline contents. Results showed that the hieghest amount of morphological triats and shoot dry weight were related to 200 µM SNP concentration under non drought stress (control) condition. The highest amount of RWC was obtained (97.9%) in 90% moisture treatment (control) and 200 µM of SNP. Also, higher concentrations of SNP (200 and 400 µM) under moderate stress (60% of crop capacity), could increase the plant drought stress tolerance by increasing the SOD and POD enzymes activity as well as reducing MDA content. The highest amount of proline (16.7 µmol/g fr wt) and total phenol (127.7 mg GAE/g dry matter) were also related to 400 µM SNP treatment. In general, SNP foliar application especially at 200 µM concentration under drought stress conditions could modify drought stress damage, and increase active ingredient of the plant.

کلیدواژه‌ها [English]

  • Antioxidant Enzymes
  • essential oil content
  • Foliar Application
  • nitric oxide
  • oxidative stress
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