A diallel method was employed in which eight genotypically diverse lines of mungbean were crossed among themselves in all possible combinations excluding reciprocals. The mean square due to general combining ability (GCA) and specific combining ability (SCA) were significant for all the characters except mean square due to (SCA) for clusters per plant and seed yield per plant indicating importance of both additive as well as non-additive gene action. The estimates of variances due to specific combining ability were higher than general combining ability for all the traits except days to 50 % flowering, primary branches per plant, clusters per plant and seed yield per plant pointed out to be the preponderance of non-additive gene effects in the expression of these characters. Whereas predictability ratios were greater than the value of 0.5 for days to 50 % flowering, primary branches per plant, clusters per plant and seed yield per plant indicating the predominance of additive gene action for these characters. However, predictability ratio exhibited less than 0.5 values for rest of the characters indicating the predominance of non-additive gene action. The good general combiners for seed yield per plant were BM-4, PDM-139, ML-131, and IPM 99-125. The best specific cross combinations wereRMG-344 x RMG-1045, RMG-1035 x RMG-1045 and BM-4 x PDM-139. showed the highest positive significant SCA effect for seed yield per plant. These cross combinations could be utilized for further use in breeding programme for improvement in yield of mungbean.

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For combining ability analysis, a diallel method was employed in which eight genotypically diverse lines of green gram were crossed among themselves in all possible combinations excluding reciprocals. The analysis for combining ability revealed significant mean sum of squares of both general combining ability (GCA) and specific combining ability (SCA) for most of the characters which indicated the presence of both additive and non-additive gene actions. Higher magnitude of GCA effects than SCA effects were observed for days to secondary branches per plant, 100 seeds weight and seed yield per plant indicating predominance of these traits by additive gene effects. Higher magnitude of SCA effects than GCA effects were observed for characters pod length, seed protein content and seed methionine content pointed out to be the preponderance of non-additive gene effects in the expression of these characters. The good general combiner for seed yield was BM-4, whereas, IPM 99-125 was most promising for seed protein content and RMG-1045 for seed methionine content. The best specific cross combinations for seed yield and seed methionine content was BM-4 x PDM-139 and for seed protein content cross RMG-1035 x RMG-1045. These parents and cross combinations could be utilized for further breeding programme for improvement in yield and quality of mungbean.

Genetic divergence assessed in twenty diverse genotypes of maize (Zea mays L.) using D 2 statistics for eleven characters enabled grouping of all the genotypes in five clusters. Test weight, leaf number, harvest index, days to 50 percent flowering and plant height were the major contributors for genetic diversity among the genotypes. Cluster II was the largest contained 6 genotypes followed by cluster III which possessed 5 genotypes. The cluster I, V and IV possessed 4, 3 and 2 genotypes, respectively. Each cluster has different types of genotypes irrespective to their nature of genetic make up belonging to hybrids, composites and land races. The cluster III exhibited maximum intra-cluster distance (30.92), while maximum inter-cluster distance was noted between cluster I and III (91.55).

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