Genetic diversity for agro-morphological traits in rice germplasm

Abstract

Nature and magnitude of agro-morphological variation in 25 rice germplasm lines was studied with the help of Mahalanobis D2 statistics. Notable genetic variability in all the traits studied indicated existence of sufficient variation among the germplasm lines. Variance estimates revealed that genotypic variance contributed maximum to phenotypic variance suggesting that such variation can be exploited through selection and hybridization. Based on D2 values, 25 lines were grouped into six clusters. Among the six clusters, cluster IV consists of 9 lines, forming the largest cluster followed by cluster V (7 lines), cluster VI (5 lines), II (2 lines) while I & 3 had 1 line each. Inter cluster distances were found to be higher than intra cluster distances depicting wide diversity among the lines under study. The contribution of various characters towards the expression of total genetic divergence indicated that number of effective tillers/plant contributed a maximum level (21.86%) followed by days to 50 percent flowering (12.19%) and grain yield (11.40%). The variation present in the germplasm lines can be exploited through selection and hybridization.

Keywords

• rice germplasm
• variability
• dendrogram
• genetic divergence