Path Coefficient Analysis in upland Rice Accessions

The simple correlation coeffiicients between yield and its component characters may sometimes be misleading as it does not provide the magnitude of associations. Splitting the total correlation into direct and indirect effects of various causes give more meaningful interpretation to the cause of association between the dependent variable like yield and independent variables like yield contributing traits. The phenotypic path-coefficient analysis in fourteen quantitative traits of upland rice (Oryza sativa L.) showed that the total number of grains per panicle had maximum direct effect on the grain yield per plant followed by spikelet fertility percentage. The filled grains per panicle and total number of grains per panicle exhibited high positive and significant association with grain yield per plant, due to high direct and indirect effect of total number of grains per panicle on grain yield per plant. Some other traits like leaf length, leaf width and panicle length showed negative direct effect on grain yield per plant, but overall showed positive indirect effect through other traits resulting the positive association with grain yield per plant. Therefore, selection based on filled grains and total number of grains per panicle would be more effective as they are contributing more for yield improvement.