Morphological and Molecular Characterization of Rice (Oryza Sativa L.) Germplasm Under Direct Sown Condition.

Abstract

An experiment was carried out to assess genetic diversity at Morphological level and at DNA level for yield and its contributing characters in 25 rice genotypes at Technology Park, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, (U.P.) in Randomized Block Design with 3 replications during Rabi 2019. Analysis of variance revealed substantial amount of variability among the genotypes for all the characters under study. The estimates of PCV in all the traits studied were greater than those of the GCV. Considering heritability, most of the characters showed high values. High heritability coupled with high genetic advance (as % mean) were recorded (>30%) for biological yield per plant (97.98) followed by harvest index (69.42), grain per panicle (54.05), panicle length (33.05), plant height (31.27), no. of tillers per plant (31.16). showing that heritability might be to additive gene effects and direct selection for these traits may be successful. Genotypic correlation coefficients were higher than the corresponding phenotypic correlation coefficients in most of the traits under study. Path coefficient analysis showed that among the different yield contributing characters Seed filling period direct effect showed indirect positive effect via day to maturity, days to 50% flowering and plant height had positive and direct effect on grain yield per plant. The distribution pattern of genotypes in different clusters was random. The highest numbers of genotypes were founded in cluster II (six). The inter-cluster distance was greater than intra-cluster distances in revealing considerable amount of genetic diversity among the genotypes studied. The intra-cluster was maximum in cluster III reveals maximum genetic diversity followed by cluster VI The inter-cluster values of the six clusters revealed that maximum inter-cluster generalized distance was between cluster I and cluster VI exhibited maximum divergence followed cluster III and VI While, the lowest was between cluster II and cluster VI. Genotypes from the same geographical region fell into different clusters and vice- versa. This suggested that selection of parents for hybridization should be on genetic diversity rather than on the geographical areas. In present study, a total of 15 primers of SSR markers were evaluated for their efficiency of polymorphism across 25 improved varieties of rice in which a total 6 polymorphic band and 2 monomorphic band were obtained with an average of 1.33 bands per primers. The approximately product size ranges from 200 bp (HvSSR01-32) to 350 bp (HvSSR01-41), the PIC value ranged from the minimum value 0.1536 for primer (HvSSR01-53) to maximum value 0.8704 for the primer (HvSSR02-50), with an average value of 0.5008 for all polymorphic SSR primers. The resolving power of 6 polymorphic SSR primers varies from 0.1296 (HvSSR02-50) to 0.8464 (HvSSR01-53) with an average value of 0.4992. Significant genetic variation was found among all the genotypes with Jaccard's similarity coefficient ranging from 0.038 to 1.00. Dendrogram based on SSR marker analysis grouped the genotypes into two major clusters and two sub clusters and so on. These markers are valid and will make a contribution to the studies in diploid rice (oryza sativa L.)