GENETIC DIVERSITY, CORRELATION AND PATH CO-EFFICIENT ANALYSIS IN SOYBEAN (Glycine max (L.) Merrill)

Abstract

A field experiment was conducted during December, 2011 to April. 2012 to study the genetic variability, correlation, path coefficient analysis and genetic diversity for quantitative traits in soybean ((ilycine max (L.) Merrill ) with 28 genotypes in randomized complete block design with three replications. The genotypes were placed in a field experiment conducted at the research farm of Shcr-e-Bangla Agricultural University. Dhaka- 1207. Analysis of variance for each trait showed significant differences among the genotypes. Phenotypic coefficients of variation (PCV) was close to genotypie coefficients of variation ((;CV) for all the characters except pod length and seeds per pod indicating that environment had influence on the expression of these characters. High heritability associated with high genetic advance percent of mean was observed for plant height, number of branches per plant, pods per plant, seeds per plant and hundred seed weight which indicated that selection for these characters would be effective. Seed yield per plant had highly significant positive genotypic and phenotypic association with plant height, branches per plant, pods per plant, pod length, seeds per pod, seeds per plant and hundred seed weight revealing that selection based on these traits would ultimately improve the seed yield. Path coefficient analysis revealed that seeds per plant and hundred seed weight had the highest positive direct effect on seed. Hence, thrust has to be given for these characters in future breeding programme to improve the yield in soybean. Multivariate analysis based on II characters indicated that the 28 genotypes were grouped into five distant clusters. The maximum contribution of characters towards diversity was observed by days to first flowering, number of pods per plant and seeds per pod. Thus, these traits may be given high emphasis while selecting the lines for hybridization. The inter cluster distance was maximum between cluster II and cluster IV. The highest intra cluster distance was found in cluster V. From the results it can be concluded that the following genotypes viz., F-85-1 1347 (04). LG-92P-12-18 (08). RI4174-75 (023) and MTD45 I (G28) were identified as potential genotypes for higher seed yield in soybean.