Combining ability study was carried out in a 10 x 10 diallel set of dry beans (Phaseolus vulgaris L.) for seed yield and its component characters. The 45 F1s generated by crossing ten diverse lines and their parents were evaluated in Randomized Block Design (RBD) in two replications at three locations during Kharif, 2008. Analysis of variance revealed that both gca and sca were influenced by environments, which suggested that studies be conducted over environments to get unbiased estimates. The sca x environment interaction was greater than gca x environment interaction for most of the traits. The relative magnitude of gca and sca variation indicated that greater magnitude of sca variances for all the traits, indicating greater importance of non additive gene action for the inheritance of these traits. SKUA-R-607 and SKUA-R-608 showed high combining ability for seed yield and yield attributing traits. The most promising crosses in order of merit for seed yield were Shalimar Rajmash 1 x SKUA-R-607, SKUA-R-608 x SKUA-R-106 and Shalimar Rajmash -1 x SKUA- R-612. These promising crosses may be improved through conventional breeding methods such as biparental mating and diallel selective meeting, thereafter followed by pedigree method of selection, so as the tight linkage, if any, may be broken and transgressive segregants may be isolated. DOI: http://dx.doi.org/10.3329/sja.v10i2.18324 SAARC J. Agri., 10(2): 61-69 (2012)

Study on genetic variability, character association and path analysis was carried out with sixty chrysan-themum genotypes keeping in mind of their applicability in future crop improvement programmes. High phenotypic and genotypic coefficient of variation were found for the character such as number of flower per plant, number of branches per plant, number of primary branches, number of secondary branches, plant spread and plant height. High heritability coupled with high expected genetic advance was observed for number of flower per plant, number of secondary branches and branches per plant. In general, genotypic correlation coefficients were found to be higher than the phenotypic correlations for most of the characters. Number of flowers per plant showed highly positive significant correlation at both genotypic and phenotypic level with plant spread (0.977,0.974), number of primary branches (0.952,0,828), number of branches per plant (0.956, 0.950), number of flower per spray (0.932, 0.821) and number of secondary branches (0.770, 0.744). Path analysis revealed that plant spread, number of primary branch-es, number of flower per spray and number of branches per plant had highest positive and direct effects on number of flowers per plant at genotypic and phenotypic levels. Thus, the useful cultivars can be used as parents in hybridization programme to obtain admirable progenies

Climate change has been a threat to food security challenges. Climate change presents an additional stress on food security challenges as it affects production of food in many ways. Among various stresses, drought is a big concern and rising at an alarming rate with climate change. Scientific approaches are being tried to understand the mechanisms of drought stress. The emergence of new molecular biology approaches and new sequencing as well as phenotyping platforms good research progress has been made in regard to drought and drought resistance mechanisms via identification of quantitative trait loci or genes responsible for drought tolerance mechanisms through Qtl mapping, Family based Qtl mapping, Linkage disequilibrium, Structural and Functional genomics approaches. Genome wide selection methods have been used for the current world concern of drought which will eventually lead to climate resilient crops and will solve the problem of food insecurity in near future. Huge data are being derived from genome wide selection (GWS) studies at the transcriptomics, proteomics and metabolomics levels, but how efficiently to explore and exploit these data to extract the essential functional pathways or networks for genetic improvement of drought resistance remains a significant challenge.

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