Evaluation of genetic variation within Brassica juncea Genotypes using biochemical and morphological markers

Genetic variability among 59 Brassica juncea genotypes was assessed, based on morphological and biochemical markers. The traits studied were days to 50% flowering, days to maturity, plant height, seeds/siliqua, siliqua/plant, test weight, seed yield/plant, protein content, oil content, glucosinolate content and fatty acid composition and SDS-PAGE of seed protein. Data on morphological, chemical and SDS-PAGE markers were analyzed using NTSYS-PC and the multivariate statistical procedures: cluster analysis (UPGMA) and principal component analysis. Analysis of variance for morphological traits reflected significant differences among genotypes. Phenotypic Coefficient of Variation (PCV) for different characters ranged from 3.055 to 36.521%. Brassica juncea genotypes could be classified, based on morphological traits, into six clusters and 94.59% of the variance among the genotypes was explained by four PCAs. Based on quality traits they were clustered into five groups as 90.09% of variance was explained by four principal components. Protein content, palmitic acid, stearic acid and linoleic acid had higher variances. Based on the SDS-PAGE pattern all genotypes were classified into five clusters. The greatest genetic dissimilarity was between LG-2005-4-7 and PLEM-2005-7, showing their potential to be suitable parent in a crop improvement program.