Interrelationship of genetics parameters for quantitative and physiological traits in rice under irrigated and drought conditions

High estimates of heritability, genetic advance, genotypic and phenotypic coefficients of variation (GCV and PCV) recorded for apparent contribution rate (h2:98.79, 92.23, PCV: 50.23 and GCV: 49.93) under irrigated condition while, apparent contribution rate, grain yield plant-1 and biological yield plant-1 under drought condition emerged as ideal traits for improvement through selection procedures. Grains panicle-1, spikelet fertility and membrane thermo stability with high heritability and genetic advance and moderate GCV and PCV appear as good indices for selection under stress condition. The very strong positive association of grain yield plant-1 was observed at both levels with biological yield plant-1 (rp=0.963, rg=0.997 in irrigated and rp=0.906, rg=0.946 in drought condition) under both the conditions followed by harvest index (rp=0.592, rg=0.613). Path-coefficient analysis identified biological yield plant-1, harvest index and grains panicle-1 as most important direct yield component while, biological yield plant-1 emerged as most important indirect yield component under irrigated condition. In drought condition, biological yield plant-1 was found to be most important direct yield contributor and harvest index, grains panicle-1, spikelets panicle-1, spikelet fertility, plant height and apparent contribution rate as direct components of secondary importance, while biological yield plant-1 was most important indirect yield attribute.