Genetic variability and association studies of some quantitative characters in winter rapeseed (Brassica napus L.)

Information of the variability and the extent and type of relationship of some quantitative characters in rapeseed is important for an efficient breeding program. In addition, the association between seed yield and quality characters, oil and protein content, is of major interest. 10 winter rapeseed genotypes were evaluated for variation, genetic and phenotypic correlations and broad sense heritability for seed yield, yield and quality characters for 2 years. The results revealed significant differences for all yield and quality characters indicated the presence of sufficient genetic variability for effective selection. Variability, broad sense heritability, genetic advance were maximum for oil yield, seed yield followed by protein yield. In addition, very strong correlations were estimated among them. Simultaneous selection regarding seed yield would be an effective way to increase oil yield and protein yield. Plant height was associated with seed yield, oil yield, protein yield, number of pods on main stem and pod length. In conclusion, plant height, pod length, oil yield and protein yield were efficient characters as selection criteria.