Identification of drought tolerant and high yielding F₂ genotypes of rice under aerobic condition

Identification of F₂ segregants for high yield and drought tolerance was envisaged by growing 250 F₂ genotypes derived from Moroberekan/IR64, japonica/indica rice cross in an augmented design under low moisture stress aerobic condition. Estimates of phenotypic coefficient of variance (PCV), genotypic coefficient of variance (GCV), heritability in broad sense (H), genetic advance as per cent mean (GAM), skewness, kurtosis and Shapiro-Wilk W test for normality were computed for eighteen drought and grain yield related traits. In all the cases except for culm angle, PCV was higher than GCV indicating the influence of environment on the characters. High H coupled with high GAM was observed for grain yield traits; Grain yield plant⁻¹, biomass yield plant⁻¹ (BY), harvest index, productive tillers plant⁻¹ and drought traits; leaf rolling (LR), spikelet fertility, panicle exsertion and plant vigor (PV) and hence offered good scope for selection. F ₂ population has recovered maximum superior transgressive segregants for PV (73.2%), BY (65.5%), panicle length (49.8%) and test weight (49.8%). The population was skewed towards female parent (Moroberekan) for some traits and for some other traits it was skewed towards male parent (IR64) with platykurtic distribution. Chi square test fit the segregation of LR in 3 (rolled): 1 (unrolled) ratio. Based on LR plasticity 64 and 45 frequencies of F ₂ genotypes were classified as highly drought resistant and drought resistant. Ten F ₂ genotypes were selected for high yielding and drought tolerant genotypes by direct selection.