Salicylic acid but not jasmonic acid improved canola root response to salinity stress

Abstract

We evaluated the effect of foliar sprays of 1 mM salicylic acid and 0.5 mM jasmonic acid on root growth of canola (Brassica napus, Cultivar: Ocapi) under different levels of salt stress (0, 40, 70, 100 mM NaCl) as a practical means to reduce water-stress. Salinity decreased the primary and lateral root length and weight, root diameter, density, shoot dry weight, shoot/root ratio and root water content, but increased the Root length/ Root weight ratio. Jasmonic acid increased the lateral root growth, but reduced the primary root growth and shoot dry weight and did not alter the root water content under different levels of salt stress. Salicylic acid had no effect on lateral root growth, but increased the primary root length, weight, diameter and root density in plants. These enhancements by salicylic acid increased the water content in root tissues and caused considerable improvement in canola growth.