Potassium nutrition improves the maize productivity under water deficit conditions

Water scarcity at critical growth stages reduces the maize productivity; however, potassium (K) nutrition can ameliorate its adversities to a certain extent. This study was conducted to evaluate the role of K nutrition in improving the productivity of maize hybrids NK-8441 and P-32B33 under water deficit (50% field capacity) at stem elongation (BBCH-36) and tasseling (BBCH-59) stage by withholding irrigations. Both the hybrids viz. NK-8441 and P-32B33 were fertilized or not with 60 kg K ha^-1 as basal application. Water deficit both at BBCH-36 and BBCH-59 stages reduced the productivity of both maize hybrids due to decrease in yield related traits. However, K application improved the grain yield of tested hybrids both under stress and optimal water conditions. Application of K also improved the root system in both tested maize hybrids. Although, K nutrition improved the net income from both tested hybrids; however, benefit-cost ratio was improved only in case of hybrid P-32B33. In crux, drought stress, particularly at BBCH-59 stage, reduced the yield of both tested maize hybrids. However, K nutrition helped in mitigating the damaging effects of drought due to well-developed root system, and accelerated the yield and net income.