GENETIC VARIABILITY AND PRINCIPAL COMPONENT ANALYSIS OF YIELD CAUSATIVE CHARACTERS IN BRASSICA NAPUS L.

Abstract

Current study was conducted at Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan during 2019-20. Genetic variability, correlation (r) and broadsense heritability (h2 BS) were studied in ten diverse accessions of Brassica napus for analysis of yield causative characters. All the genotypes were found to be significantly different from each other for all studied traits which shows variability among genotypes. High values of phenotypic co-efficient of variance (PCV) and genotypic coefficient of variance (GCV) were observed for branches on the main stem, 1000-seeds weight (g), and the number of seeds per silique which is the sign of the presence of variability in these characters. The same characters depicted the higher heritability (>50) along with high genetic advance which was the indication of an additive type of gene action. The plant height showed significant positive association with branches on main stem (r = 0.73**), thousand (1000)-seeds weight (r = 0.90**), seed yield per plant (r = 0.66*) and oil content (r = 0.65*). The branches on the main stem showed a similar association with seed yield per plant (r = 0.91**) and 1000-seeds weight (r = 0.67*). The results revealed that branches on the main stem, seeds per silique and 1000-seeds weight were improved through mass selection. Principal component analysis revealed that the first four principle components (PCs) contributed up to 95% of total variation whereas, the first PC shared its maximum in total variation and selection from this PC could be exploited in further breeding programs.