Mitigation of drought stress in spinach using individual and combined applications of salicylic acid and potassium

Drought stress is a major constraint impairing crops growth around the globe. It not only decreases the growth of crops but also converted cultivatable land into barren non-cultivatable area. The salicylic acid (SA) and recommended potassium (K) application have the potential to alleviate the adverse effects of drought stress on crops. Current greenhouse pot experiment was conducted to investigate the influence of various levels of SA and K on spinach growth under drought stress. There were three levels of SA i.e., 0 micro Molar (µM), 300 µM and 600 µM and K i.e., control (0), half recommended dose (34.5 mg / 5 kg soil) and full recommended dose (69.0 mg / 5kg). Results showed that drought stress significantly decreased shoot and root, lengths and dry weights, chlorophyll a and b, total chlorophyll and nutrients uptake. It also significantly increased electrolyte leakage in spinach leaves. However, application of SA600 + FK significantly enhanced shoot (33.3%) and root lengths (44.5%), dry weights of plants (58.1%), chlorophyll a (72.7%), chlorophyll b (115.7%) and total chlorophyll content (88.4%) in spinach under drought. More spinach growth, under drought conditions, subjected to SA600 and FK was linked with better root elongation and nutrients (N, P and K) uptake. In conclusion, co-application of SA and K has more potential to improve spinach growth under drought stress compared to their sole applications. However, SA600 and FK are more effective levels compared to SA300 and HK for the alleviation of native effects of drought in spinach. (author)