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Genetic diversity plays a crucial role in harnessing the potential of crop genotypes for genetic improvement. It helps to identify, preserve, and utilize diverse landraces effectively. This research aimed to assess the level of genetic diversity and traits enhancing genetic variation among 46 brinjal genotypes (Solanum melongena L.) in preparation for a special breeding programme to utilize the potential landraces. Genetic divergence among 46 genotypes of brinjal for eleven characters was assessed using the D² method. The studied genotypes were categorized into eight clusters. Cluster I with 15 genotypes was the largest followed by Cluster IV (14 genotypes), Cluster V (7 genotypes), Cluster VII (4 genotypes), Cluster III (3 genotypes), Clusters II, VI, and VIII with one genotype each. The intra-cluster D² values ranged from 0.00 (Cluster II, VI and VII) to 103.53 (Cluster III). The inter-cluster distances varied from 117.00 to 791.17. Cluster II and Cluster VII had the greatest inter-cluster distance (791.17), followed by Cluster II and VIII (673.41), and Cluster VII and Cluster V had the smallest inter-cluster distance (117.00). Crossing genotypes in clusters with wide inter-cluster distances improves recombinant isolation in segregating generations. The three traits-number of flowers per inflorescence (23.8%), average fruit weight (17.68%) and days to first flowering (16.81%) altogether contribute to 57.8% of the total divergence. The combination of these traits could be useful to produce high-yielding climate resilient varieties from valuable landraces. [ABSTRACT FROM AUTHOR]

An experiment was conducted with the objective of determining the magnitude of association between seedling vigour index and its component characters. Fifty rice genotypes were evaluated in completely randomized design with three replications. Correlation coefficient analysis of vigour index showed positive and significant association with total seedling length, root length, total seedling dry weight, root dry weight, shoot length, germination percentage and first leaf area under normal condition. Germination percentage, total seedling length, root length, shoot length and first leaf area showed strong and significant positive association with seedling vigour index under cold condition. Thus, these traits could play pivotal role in developing cold tolerant rice. Separation of correlation coefficients into direct and indirect effects of component traits for vigour index revealed that the traits total seedling length and root dry weight exerted maximum positive direct and indirect effect respectively on vigour under normal condition. Under cold stress the traits shoot length and root length exerted maximum positive direct and indirect effects respectively for vigour index. These characters, therefore, are required to be considered during selection for vigour improvement in rice under normal and cold condition in rice. [ABSTRACT FROM AUTHOR]

Fifty genotypes of brinjal (Solanum melongena L.) was studied for twelve traits to identify genetically diverse genotypes, for the use in cross breeding programme. Analysis of variance revealed significant differences among the genotypes for all the traits of interest. The genotypes viz., VR-2, JBH-3 and Utkalkeshari were called out as elite genotypes, based on per se performance. Clustering of 50 genotypes by utilizing the Mahalanobi's D² statistic, grouped the genotypes into as many as seven clusters. Cluster VII encompassed of with as many as 21 genotypes. Maximum inter-cluster distance was observed between cluster VI and VII. Cluster VI showed earliness coupled with high number of fruits per cluster and comprised of four genotypes. The genotypes gathered in these groups may be utilized in cross breeding programme to evolve high yielding but early lines and/or hybrids. The intra-cluster distance was maximum among the genotypes constelled with the Cluster VII. These genotypes may be utilized as parents in evolving iso-responsive lines and/or hybrids. [ABSTRACT FROM AUTHOR]

Six genotypes of rice namely, ADT36, ADT45, BPT5204, ASD16, ADT37 and ADT39 were mated in half diallel fashion. The resulting fifteen hybrids along with their parents were evaluated for grain yield and its component characters namely, days to 50 percent flowering, plant height, number of productive tillers per plant, panicle length, number of grains per panicle, 100 grain weight, kernel length, kernel breadth and kernel L/B ratio by adopting standard biometric genetic methods. The analysis of variance indicated that the parents and hybrids differed among themselves for all the ten characters studied. The analysis of variance for combining ability indicated the significance of both GCA and SCA variances, illustrating the importance of both additive and non-additive genetic variance in the expression of all the traits. When the parents were assessed for their overall combining ability, the parent namely ADT45 was adjudged as good general combiner followed by ADT39 and ASD16. Based on overall specific combining ability, the cross combinations viz., BPT5204 × ASD16, ADT45 × BPT5204, ASD16 × ADT37, ADT45 × ADT37, ADT45 × ADT39, ASD16 × ADT39, ADT37 × ADT39 and ADT45 × ASD16 were identified as good specific combiners. The cross combination BPT5204 × ASD16 exhibited the maximum standard heterosis (24.65 percent) followed by ADT45 × BPT5204, ASD16 × ADT37, ADT45 × ASD16 and ADT45 × ADT37 for the trait grain yield per plant. The cross combination which showed high commercial heterosis also registered high per se performance, significant favorable sca effect and had both the parents or at least one of the parent with high gca effects. High × High gca combinations with high sca effects might be due to interallelic interactions like complementary gene action and hence it could be used in heterosis breeding. In case of combinations with high sca effects and one of the parents with low gca effects, it would throw transgressive segregants for effective selection. [ABSTRACT FROM AUTHOR]

The study was carried out in an effort to assess the extent of genetic divergence, variability, character association and pathcoefficient analysis in 40 genotypes of rice for 8 characters viz., days to first flower, plant height, number of tillers per plant, number of panicles per plant, panicle length, number of grains per panicle, thousand grain weight and grain yield per plant. The analysis of variance indicated considerable amount of variability in all genotypes. Based on D2 analysis six clusters were formed indicating that there were no association between eco-geographical distribution of genotypes and genetic divergence. Based on the inter and intra cluster distances, the genotypes belonging to clusters II, IV, V and VI could be used for hybridization programme. The characters namely grain yield per plant, number of panicles per plant, number of tillers per plant and number of grains per panicle recorded high PCV and GCV. High heritability coupled with high genetic advance as percent of mean was observed for number of grains per panicle, plan height, thousand grain weight, number of tillers per plant, grain yield per plant and number of panicle per plant. The genetic correlation revealed that grain yield per plant had strong positive and significant association with number of panicles per plant, number of tillers per plant, number of grains per panicle and thousand grain weight. Path coefficient analysis indicated that maximum direct effect on grain yield per plant was through number of panicles per plant, number of grains per panicle and thousand grain weight. [ABSTRACT FROM AUTHOR]

Six genotypes of rice namely, ADT 36, ADT 45, BPT 5204, ASD 16, ADT 37 and ADT 39 were mated in half diallel fashion. The resulting fifteen hybrids along with their parents were evaluated for grain yield and its component characters namely, days to 50 percent flowering, plant height, number of productive tillers per plant, panicle length, number of grains per panicle, 100 grain weight, kernel length, kernel breadth and kernel L/B ratio by adopting standard biometric genetic methods. The analysis of variance indicated that the parents and hybrids differed among themselves for all the ten characters studied. Among fifteen hybrids studied, five hybrids namely, BPT5204 × ASD16, ADT45 × BPT5204, ASD16 × ADT37, ADT45 × ASD16 and ADT45 × ADT37 exhibited maximum significant grain yield per plant and also recorded more than 30g of grain yield per plant. The hybrid BPT5204 × ASD16 (24.65 percent) recorded the maximum standard heterosis followed by ADT45 × BPT5204, ASD16 × ADT 37, ADT45 × ASD16 and ADT45 × ADT37 for the trait grain yield per plant. [ABSTRACT FROM AUTHOR]