Salicylic acid role on soybean (Glycine max L.) growth in drought stress

Abstract

Salicylic acid (SA) is an endogenous plant growth hormone responsive to drought stress. Therefore, this study was conducted to assess the exogenous SA impact on soybean (Glycine max L.) growth under drought stress conditions. An alcohol-carbohydrate, mannitol, at seven concentrations (0, 20, 25, 30, 35, 40, and 45 g/L) was used to determine the drought condition. The SA supplement in MS medium (0.5; 1.0; 1.5 and 2.0 mg/L) and the seed pretreatment with SA (2, 4, 6, and 8 mg/L) were used. Results showed that applied treatments significantly influenced soybean growth in drought stress condition. The supplement of 1.0 mg/L SA into medium and the seed pretreatment with 6.0 mg/L SA performed superior to improving the seedling growth under the drought stress. The SA presence not only improved the relative water content of leaves but also increased content of chlorophyll a and photosynthesis intensity.