Genetic variability and association analysis of advanced lines and cultivars following intervarietal and interspecific crosses in blackgram.

Genetic variability, heritability, genetic advance and correlation coefficient were analyzed for morphological, yield and yield contributing traits in 34 blackgram genotypes including one mungbean genotype and two check varieties namely, Pant U-31 and Pant U-40. The range of variability was high for days to maturity (84.3–90.3), plant height (41.5–65.3) and days to 50% flowering (33.3–40.0). The GCV and PCV estimates were highest for grain yield/plant (GCV=17.10%, PCV=35.95%) and lowest for days to maturity (GCV=1.66%, PCV=2.08%). Highest heritability was observed for 100-seed weight (93.4%) followed by days to 50% flowering (65.7%) and days to maturity (64.0%). High heritability estimates suggested that large amount of phenotypic variance was attributable to the genetic variance. High genetic advance coupled with moderate heritability estimates for 100-seed weight and grain yield/plant suggested role of both additive and non-additive gene action on the characters. Correlation coefficient anlaysis revealed that genotypic correlation coefficients were in general superior in magnitude to their corresponding phenotypic correlation coefficients. Days to maturity showed highly significant positive genotypic correlation with days to 50% flowering, whereas days to 50% flowering had negative genotypic and phenotypic correlation with grain yield/plant, suggesting that caution should be exercised not to lose yield while breeding for earliness.