VANISRI, SALEENA, DASARI2017-01-032017-01-032016http://krishikosh.egranth.ac.in/handle/1/94077A set of 112 genotypes were evaluated for morphological and molecular genetic diversity in both rabi 2014-15 and kharif 2015-16 to estimate various genetic parameters for yield and yield related traits. The experiment was laid out in a randomized block design with two replications in both the seasons. Analysis of variance indicated the existence of significant differences among the genotypes for the characters studied in both kharif and rabi. In general, the phenotypic coefficient variance (PCV) of all traits were higher than the genotypic coefficient variance (GCV), indicating the environmental influence on the expression of these traits. However, these differences are relatively low in case of plant height and 1000 grain weight, when compared to other characters in both kharif and rabi, suggests that these characters are under major influence of genetic control and less due to environmental factors. The 1000 grain weight, single plant yield, filled grains per panicle, total grains per panicle and plant height had high heritability coupled with high genetic advance as percent of mean in both the seasons indicating that these traits are under additive gene control and can be improved through simple selection procedures. 48 The 112 germplasm were grouped into 6 and 12 divergent clusters in kharif and rabi respectively using Mahalanobis D2 analysis. The days to 50% flowering followed by plant height, 1000 grain weight and panicle length contributed more than 85 per cent of the total genetic divergence during kharif and rabi. D2 values indicated that the crossing between the lines viz.,Udayagiri,Vajram and Pantdhan12 with Taramati; MTU1121, R.P bio-248, IR-64 andSnehawith Udayagiri,Vajram and Pantdhan12 during kharif and WGL 915, Pokkali with Siddhi and N22, NL-61, T309, Abhilash with JGL 11470, JGL 1798, Acharmati, and P1144 in rabi may generate useful segregants for yield improvement. Genetic diversity among 112 rice genotypes was estimated based on the Jaccard‟s pair wise similarity co-efficient using 12 polymorphic yield related gene specific SSR markers. The polymorphism information content (PIC) ranged from 0.51 to 0.83 with a mean of 0.70. The unweighted pair group arithmetic average tree based dendrogram constructed using DARwin distributed the 112 rice genotypes into three clusters consisting of 40, 44 and 28 genotypes, respectively. Markers specific to number of productive tillers and number of grains per panicle contributed majorly towards higher yield in cluster I, whereas, in cluster II, markers for number of productive tillers, 1000 grain weight and number of grains per panicle have played major role in determining the yield levels. While, in cluster III, specific markers for 1000grain weight contributed more towards higher yield. Hence, the selection for high yield can be achieved by selecting the lines based on the respective gene linked markers for yield related traits. Comparison of genetic diversity assessments based on morphological and molecular data by Mantel test indicated significant correlation between them. Therefore, with the present combination of morphological and molecular-based diversity analyses, the germplasm lines Udayagiri, IR 1552, HIM 799, NLR34242, RNR19186, MTU1010, Vasumati and T309 can be utilized in further breeding programmes based on their morphological and molecular superiority for yield and yield related traits.enThesis