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The Indian bean is a well-known legume and green vegetable crop in India. An attempt was made to analyze the diversity pattern in selected recombinant inbred lines (RILs) of determinate type of Indian bean using principal component analysis (PCA) and D2 statistics. Data from eleven yield component traits were used to carry-out the analysis. Clustering of lines was performed using modified (sequential) tocher method, and results were also compared with original tocher method. PCA analysis showed that first three principal components collectively accounted for 68.92% of total variation among the genotypes and had eigenvalues >1. The lines were grouped into five clusters using modified tocher method for cluster analysis, which has been shown to be superior to tocher method. Cluster-I and cluster-IV showed the highest inter-cluster distance (124.92) and crossing between genotypes from these two clusters was suggested to get desirable segregants. The study also suggested that PCA and D2 analysis can be used alternatively to assess the genetic diversity pattern among genotypes. [ABSTRACT FROM AUTHOR]

The experiment was carried out to determine the genetic variability parameters and character associations for eleven quantitative traits in Indian bean genotypes. It revealed a significant amount of variability present among these genotypes. Seed yield per plant had high Genotypic coefficient of variation (GCV) and Phenotypic coefficient of variation (PCV) values, showing the potential for improvement by selection. Racemes per plant, pods per raceme, pods per plant, and pod weight had moderate GCV and PCV values. There was high heritability combined with a high genetic advance for pod weight and seed yield per plant. Plant height, pods per plant, and pod weight were significantly and positively associated with seed yield per plant. Pods per plant had the most positive direct effect on seed yield per plant, followed by racemes per plant, plant height, pod weight, pod length, and seeds per pod. Therefore, selection for such traits is advised to bring about improvement in Indian beans. [ABSTRACT FROM AUTHOR]

Seven genotypically diverse lines of mungbean were crossed in diallele fashion to identify genotypes with high general combining ability and specific cross combinations with high specific combining ability for yield and yield attributes in rabi season excluding reciprocals. The analysis for combining ability revealed significant mean sum of squares due to general and specific combining ability for all the characters studied indicating importance of both additive as well as non-additive gene effects involved in the expression of all the characters. Higher magnitude of general combining ability variances for most of the traits except for number of branches per plant, pod length, number of seeds per pod and harvest index pointed out the preponderance of additive component of the genetic variance in the expression of the characters under study. The good general combiners for yield attributing traits were Co-4, GBM-1 and Meha and the best specific cross combinations having the highest SCA effect for yield and yield attributing traits were Co-4 x Meha, Co-4 x GBM-1, Rm-9-126 x Rm-9-134, GBM-1 x Meha and Rm-9-133 x GBM-1. This cross combinations could be utilized for further breeding programmes for the development of rabi mungbean varieties with chilling tolerant ability or photo-thermo insensitivity, so as to exploit potential of rabi mungbean in rice fallows of heavy rainfall zone. [ABSTRACT FROM AUTHOR]

Twenty one crosses resulting from 7 × 7 diallel excluding reciprocal were studied to know the magnitude of heterosis over better parent and standard variety for yield and its attributing characters in rabi mungbean. The highest heterosis to the extent of 37.23% over the check Co-4 and 82.20% over the check GBM-1 was observed in cross combination Co-4 × Meha for seed yield per plant, which also exhibited high heterosis percentage for yield and yield components. The promising hybrids viz. Co-4 × Meha, Co-4 × GBM-1, GBM-1 × Meha and Rm-9-129 × Co-4 were identified which have great potential to exploit the hybrid vigour or to isolate the desirable segregants for the development of rabi mungbean varieties with chilling tolerant ability or photo-thermo insensitivity, so as to exploit potential of rabi mungbean in heavy rainfall zone as rice fallows. [ABSTRACT FROM AUTHOR]