Effect of Salicylic Acid Application on Growth and Development of Green Onions Grown Under Salt Stress

Abstract

Soil salinity negatively affects crop production and leads to loss of agricultural lands worldwide. In Iraq, poor agricultural practices, such as inadequate drainage facilities and low water quality, are known to be caused soil salinization. Onion (Allium cepa L.) is an economic crop that is consumed heavily as green or dry bulb onion. The cultivated area of green onion was statistically decreased in the Kurdistan region, Iraq, lately. Therefore, this study was conducted in the Directorate of Agriculture, Ankawa, Erbil, to examine whether salicylic acid (SA) mitigate the effect of salt stress and improve the growth and development of green onions. Two different concentrations of NaCl (20 and 40 mM) were injected around the base of each plant and after 24h, SA (0.5 and 1mM) was sprayed to the vegetative parts of each plant, evenly. The results showed that the short-term application of SA was reduced the impact of NaCl. The number of green leaves, leaf area, plant height, root growth, bulb diameter, plant weight and total yield (t. ha-1) was improved by the application of SA. It has been suggested the application of a commercial or SA analogue to the agricultural saline land may alleviate the salt stress and improve the product.