Genetic variability, cause and effect analysis for yield components and phosphorous content in rice (Oryza sativa L.) genotypes

Abstract

Thirty rice genotypes were evaluated for ten morphological traits along with phosphorous content in shoot and grains to examine the nature and magnitude of variability, character association and path coefficient. Among all traits, single plant yield exhibited the highest estimate of PCV and GCV followed by shoot phosphorous content, number of productive tillers per plant, number of tillers per plant, number of filled grains per panicle and hundred grain weight indicated that choice of these traits would be valuable. High heritability jointly with high genetic advance as percent of mean were observed for hundred grain weight, days to 50 per cent flowering, number of filled grains per panicle, plant height, single plant yield, shoot phosphorous content, number of productive tillers per plant, number of tillers per plant and grain phosphorous content indicated that these characters were governed by additive gene action. Hence genetic improvement through selection for these traits may be more helpful. Shoot P content showed negative non-significant association and grain P content had nonsignificant positive connection with grain yield. Reduced shoot P content is related to increased P use efficiency for grain production. Hence these traits may be useful for developing genotypes tolerant to phosphorous deficiency. Path coefficient analysis revealed that the highest direct effect on grain yield per plant was exerted by number of productive tillers per plant followed by plant height, grain P content, days to 50% flowering, hundred grain weight and shoot P content showing its more accountability for higher grain yield.