Genetic variability analyses for yield and physiological traits in groundnut genotypes

Abstract

Twenty different groundnut genotypes were evaluated in a randomized block design with three replications during kharif 2012 to study the variability parameters, heritability, genetic advance, correlation coefficient and path analysis for ten characters. Analysis of variance revealed highly significant differences among genotypes for all the traits except SCMR45DAS indicating that adequate variability was found in the genotypes studied for these characters. The characters like 100 kernel weight, SCMR75DAS, SLA75DAS and rust had high heritability with high genetic advance as per cent of mean and medium genotypic coefficient of variation indicating greater role of additive gene effects on these traits. While pod yield had moderate GCV and heritability along with high genetic advance as per cent of mean revealed that this character is also governed by additive gene effects and selective would be effective even in the early generation. Days to maturity, shelling outturn and SLA45DAS had moderate heritability accompanied with low GCV and genetic advance indicating these traits are governed by non-additive gene effects. Selection may be practiced in later generations for improving these traits. The results on genotypic correlation coefficients revealed that pod yield had significant highly positive correlation with days to maturity, 100 kernel weight, and SCMR45DAS while it was negative and significant for days to flower initiation and rust. SCMR45DAS and SCMR75DAS had highly significant negative correlation with SLA45DAS and SLA75DAS. SLA45DAS had highly significant negative correlation with rust. Therefore, SCMR value could be used to identify genotypes with low SLA and rust resistant genotype. Path analysis indicated that 100 kernel weights had high positive direct effect with highly significant positive correlation with pod yield. Hence this character may be effective for selection of high pod yield.