Effect of water stress on growth, yield and yield components of rice (Oryza sativa L.) genotypes

This study aimed to examinate effects of drought stress on rice agronomical traits and identify rice genotypes and elite lines that are tolerant to drought. Twenty genotypes consisting of seventeen inbred lines, two parental lines (IR64 and B6144F-MR) and drought tolerant variety APO were evaluated in a split plot design with four replications in experiment with and without water stress. Analysis of variance results indicated that the effects of genotype and drought stress were highly significant for day to 50% flowering, panicle leaf length, panicle leaf width, plant height, panicles number per m2, 1000 grains yield and grains yield. Genotype, drought stress, and Genotype × drought interaction was highly significant for day to 50% flowering, plant height and grains yield. Number of tillers m2, panicle leaf length, plant height, 1000 grains weight, biomass and grains yield were decreased with increasing water stress level; however, day to 50% flowering and panicles number per m2 were increased. Responses of the rice genotypes in water stress varied significantly. There had been different degree of reduction to the yield contributing characters for the stress. From the findings of this study genotypes APO, IRB-MR-412 and B6144F-M showed best drought tolerant level, as these genotypes gave significantly higher yield than the other genotypes under study.