INTERGENOTYPIC VARIABILITY STUDY IN ADVANCED LINES OF Brassica rapa

Abstract

An experiment was carried out with 58 genotypes of Brassica rapo including three commercially cultivated varieties as check to study their intergenotypic variability. eon-elation, path co-efficient analysis and genetic divergence considering 10 different morphological characters at the experimental farm of SAl!. l)haka during November 2007 to March 2008. Significant variation was observed among all the genotypes for all the characters studied except thousand seed weight. High CICV value was observed for number of secondary branches per plant. High heritability values along itli high genetic advance in percentage of mean were obtained for days to 50% flowering. number of secondary branches per plant, seeds per siliqua. and siliqua length. Highly significant positive association of seed yield per plant was observed with number of primary branches per plant, number of secondary branches per plant. number of siliquae per plant. Path analysis showed that, yield per plant had the highest direct effect on flumL)Cr of primary branches per plant, number of siliquac per plant, number of secondary branches per plant and number of seeds per siliqua. By using different multivariate analysis techniques all the genotypes were grouped into 6 clusters. PCA. PCO and ('V.A analysis gave almost similar result. Cluster II and III had maximum (13) and cluster IV had minimum (6) number of genotypes. The highest inter cluster distance was observed between cluster Ill and Vi and the lowest between cluster 11 and IV. highest intra-cluster distance was observed in cluster VI. Plant height, number of secondary branches per plant and seeds per siliqua contributed maximum towards divergence. Considering diversity pattern, genetic status and other agronomic performances. line 39 and line 44 from cluster I; line 42 from cluster H; line 2, line 43 and line 45 from cluster V: line 50. Line 52, line 54 and line 58 from cluster VI- might he selected as suitable parents in future hybridization program.