Salicylic acid: an effective growth regulator for mitigating salt toxicity in plants

Document Type : Review Paper

Authors

Department of Plant Ecophysiology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

Abstract

Salinity is a harmful environmental factor threatening plant growth and productivity through ionic and oxidative stresses. These detrimental effects of salinity could be modulated by some plant growth regulators. Salicylic acid (SA) as a phenolic molecule regulates growth and development and also induces crucial defense mechanisms in plants under salinity. This growth regulator can also improve some physiological and biochemical processes of salt-stressed plants such as reducing Na+ influx to the root cells and increasing essential nutrients uptake. Application of SA can also help plants to accumulate the toxic Na+ in vacuoles through enhancing the activities of H+-pum- stressed plants. Some reports indicate that salicylic acid counteracts salt-induced water deficit by elevating plant osmolytes including soluble sugars, proline, and glycine betaine. These essential roles as well as the effect of SA in the augmentation of chlorophyll and photosynthetic activities can potentially improve plant growth and productivity under saline conditions. The possible cross-talks of salicylic acid with other growth regulators are also important for promoting salt tolerance and the performance of plants under stressful conditions. 

Keywords


Article Title [فارسی]

سالیسیلیک اسید: یک تنظیم کننده رشد مؤثر برای کاهش سمیت نمک در گیاهان

Authors [فارسی]

  • سهیلا عبدلی
  • کاظم قاسمی گلعذانی
گروه اکوفیزیولوژی، دانشکده کشاورزی، دانشگاه تبریز، تبریز.
Abstract [فارسی]

شوری یک عامل محیطی مضر است که از طریق تنش­ های یونی و اکسیداتیو رشد و تولید گیاه را تهدید می­ کند. این اثرات زیان­بار شوری می­ تواند توسط برخی تنظیم کننده­ های رشد گیاهی تعدیل گردد. سالیسیلیک اسید (SA) به عنوان یک مولکول فنلی رشد و نمو را تنظیم کرده و مکانیسم ­های دفاعی حیاتی گیاهان را تحت تنش شوری القا می­ کند. این تنظیم کننده رشد می ­تواند برخی فرایند­های فیزیولوژیکی و بیوشیمیایی گیاهان تحت تنش شوری مانند کاهش ورود سدیم به سلول­ های ریشه و افزایش جذب عناصر غذایی ضروری را بهبود بخشد. کاربرد SA همچنین می­ تواند از طریق افزایش فعالیت پمپ­ های پروتونی به ذخیره سدیم سمی در واکوئل گیاهان کمک کند. این هورمون گیاهی ظرفیت آنتی­اکسیدانی (آنزیمی و غیر آنزیمی) گیاهان تحت تنش شوری را به طور قابل توجهی افزایش می­ دهد. برخی گزارش ­ها نمایانگر آن است که سالیسیلیک اسید از طریق افزایش محتوای اسمولیت ­ها از جمله قند­های محلول، پرولین و گلایسین بتائین با کمبود آب ناشی از شوری مقابله می­ کند. این نقش­ های اساسی و همچنین اثرات SA در افزایش کلروفیل و فعالیت­ های فتوسنتزی می­ تواند قابلیت رشد و تولید گیاهان را تحت تنش شوری بهبود دهد. روابط احتمالی سالیسیلیک اسید با سایر تنظیم کننده ­های رشد هم در بهبود تحمل شوری و عملکرد گیاهان در شرایط تنش ­زا اهمیت دارند.

Keywords [فارسی]

  • آنتی اکسیدان
  • تحمل شوری
  • سالیسیلیک اسید
  • فعالیت فتوسنتزی
  • کلروفیل
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