Interactive Effect of Salinity and Potassium on Maize Yield

A pot culture experiment was undertaken during January 2021, in the greenhouse of Institute of Agriculture Science (IAS), SOA Deemed to be University, Bhubaneswar, Odisha to study the interactive effects of salinity and potassium levels on biomass yield, accumulation and uptake of K and Na by maize. The experiment was conducted in 2-factorial CRD with three replications and twelve treatments consisting of two levels of irrigation water (SW0- normal water EC-0.5 dS m-1,SW1-saline water @ 8 dS m-1), two sources of K fertilizers (KCl and K2SO4), and three doses of K (K1-0,K2-60and K3-120 kg ha-1). The results showed that continuous application of saline water (8 dS m-1) increased the soil ECe ( Electrical Conductivity of a saturated soil Extract) by 182-360 % over normal water treatments. Application of K (120 kg ha-1) significantly decreased ECe by 29%, significantly increased the biomass yield (24%), K accumulation (14%), K uptake (41%) and decreased Na content ( 17% ) over K control. The K+/Na+ ratio in maize in saline treatments decreased by 64% over normal water. Application of K @120 kg ha-1 significantly increased the K+/Na+ ratio by 27% over K control. In saline stress environment, K+/Na+ ratio in plant fairly correlated with biomass yield (R2=0.73), K content (R2=0.79), and Na content (R2=0.89) in the plant. K+/Na+ ratio in soil failed to correlate well with biomass yield. K+/Na+ ratio in the plant can be considered as the best indicator in evaluating crop performance in saline soil.