Genetic variability, correlation and path analysis of grain yield, grain quality and its associated traits in EMS derived M4 generation mutants of rice (Oryza sativa L.)

A study was conducted to assess the grain yield and its related yield components to establish a reliable selection criteria for evolving high yielding varieties in rice. The EMS derived M4 mutants of Anna(R) 4 rice cultivar was used for assessment of variability and association of yield and yield related traits. Phenotypic co-efficient of variation were invariably slightly higher than the genotypic co-efficient of variation, which indicated mild role of environment on the expression of these traits. However, moderate to high heritability estimates coupled with high genetic advance for the traits viz., number of grains per panicle, panicle weight and single plant yield renders the phenotypic selection more effective, since these traits were under the control of additive gene action. Association studies revealed that the number of grains per panicle, panicle weight and hundred grain weight showed positive significant correlation and direct effect towards grain yield in mutant population. The reduction of grain size and hundred grain weight ultimately increased the maximum number of grains per panicle.