Waterlogging resistance in maize in relation to growth, mineral compositions and some biochemical parameters

Nine genotypes of maize were grown in polythene bags containing 1.50 kg of garden soil. Plants were subjected to waterlogging stress after 14 days of sowing. Observations pertaining to dry matter accumulation, leaf area, leaf rolling, leaf conductance, chlorophyll content, soluble protein content and superoxide dismutase (SOD) activity in leaves, and nitrogen, phosphorus, and potassium contents in various plant parts were determined in normal and waterlogged plants between 22 to 25 days of waterlogging treatment. Genotype CML-49 registered minimum reduction in dry matter accumulation and CML-80 the maximum. Accordingly they were classified as resistant and susceptible to waterlogging stress, respectively. The resistant genotypes registered lesser reduction in leaf area, chlorophyll content and leaf conductance under waterlogged condition compared to susceptible ones. SOD activity, nitrogen and potassium contents decreased but phosphorus and sodium contents increased under waterlogging condition. Resistant genotype maintained lesser reduction in SOD, N and K contents. It is suggested that high level of K, in resistant genotype is advantageous in maintaining plant water relation and leaf conductance, while relatively higher level of SOD prevents oxidative damages. It is observed that genotype which require low level of N for normal growth, tolerates waterlogging stress.