Alleviation of salinity effects by exogenous applications of salicylic acid in pearl millet (Pennisetum glaucum (L.) R. Br.) seedlings

Abstract

Experiments for the study of alleviation of salt stress effects by exogenous applications of salicylic acid (SA) in pearl millet (Pennisetum glaucum (L.) R. Br.) seedlings were conducted in soil filled earthen pots
having size 12 inches with 7 kg soil. Three treatments comprising, control (T₀), 50-mol m^-3 NaCl (T₁) and T₂ are having NaCl (50 mol m^-3) + SA (50 mg l^-1). Pots were arranged in completely randomized design (CRD) with 6 replicates. NaCl significantly reduced the plant and root lengths, plant fresh and dry weights. In contrast, NaCl did not show any adverse effect on plants treated with NaCl plus SA. Salicylic acid
treated pearl millet plants under NaCl salinity strongly reduced accumulations of Na⁺, K⁺, Ca²⁺ and Cl⁻ and glycinebetaine (GB) and total soluble carbohydrates (TSC) as compared to NaCl treatments. Higher N and relative water contents (RWC) was noted in T₂ (NaCl + SA) but it reduced in T₁ (NaCl) as compared to control. It was concluded that SA could be used as a potential growth regulator to improve salt tolerance in plants.

Keywords: Exogenous, salicylic acid, growth, ion contents, salt tolerance, pearl millet