Current study was conducted to estimate the genetic diversity of 29 local rice cultivars including 3 checks at both morphological and molecular level during Kharif 2017 in an augmented design. Significant results obtained from ANOVA of 29 genotypes for 16 quantitative traits; Mahalanobis' D 2 grouped the total genotypes into 6 clusters. Highest inter-cluster distance was found between clusters III and VI indicating the genotypes in these clusters are most diverse. The SSR banding pattern revealed a total of 65 alleles from 21 polymorphic markers across 29 rice genotypes with an average of 3.09 alleles. The polymorphism information content (PIC) values ranged from 0.701 (RM 277) to 0.346 (RM237) with a mean value of 0.571 showing the marker RM277 as best based on the above study. The dendrogram analysis revealed all the 29 genotypes were grouped into two main clusters i.e. cluster I and cluster II with dissimilarity coefficient 0.36. Both the clusters were further divided into two groups each of which are further divide into two sub-groups each. Based on the genetic distances and the dissimilarity coefficient obtained from both morphological and molecular analysis, genotypes like Bahubali, Golden 105, Pusa 1121, HUR-1301, RK-2 Lal kasturi and Pan 815 can be selected and used as parents due to their greater diversity. Knowledge of genetic diversity available within a population at both morphological and molecular level helps the breeder to formulate a successful hybridization programme and gain good results.

Assessment of variability and trait associations in a crop helps to enhance selection efficiency. With this objective, a study was conducted to estimate the genetic variability, character association and path coefficient analysis for grain yield and its component traits in 80 rice genotypes during Kharif-2020. Eighty genotypes including eight checks were evaluated in alpha lattice design with three replications. For all of the traits studied, the results revealed significant variance in all genotypes.PCV was found to be slightly more than the corresponding GCV for all the characters, indicating the role of environment in the expression of these traits. However, high GCV and high PCV were observed for number of effective tillers, grain yield per plot, number of filled grains per panicle, number of unfilled grains per panicle, biomass yield, harvest index, grain yield per plant and grain yield per hectare. Furthermore, all of the variables investigated had strong heritability and high genetic progress as a percentage of mean, with the exception of days to 50% blooming, days to maturity, and kernel breadth. Days to first flowering, days to 50% flowering, days to maturity, spikelet fertility percentage, number of filled grains per panicle, harvest index and kernel length showed a significant and positive association with grain yield per plot. Highest direct contribution to grain yield per plot was manifested by kernel length, harvest index and spikelet fertility percent. Days to first flowering, days to maturity, number of effective tillers, number of unfilled grains per panicle, test weight, biomass yield were also found to exert a positive effect on yield, thus can be considered as desirable traits for selection in high yielding genotypes.

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Rice (Oryza sativa L.) is the source of energy and nutrition for more than half of the world’s population hence it is a crop of global significance. Breeding of mineral dense rice varieties is the main target of biofortification strategy to address micronutrient malnutrition globally. Landraces and local genotypes are proven sources of novel alleles and are a promising donor for high grain mineral. A parental polymorphism survey is a prerequisite of any QTL mapping experiment. Present study consisting of SSR markers based parental polymorphism survey at IRRI South Asia Hub ICRISAT, Hyderabad. Parents of mapping population viz Rajendrakasturi (short grain aromatic rice variety with low grain zinc content) and URG-30 (a local genotype from Eastern Uttar Pradesh with high grain zinc content) were screened with 1013 microsatellite markers covering the entire length of all 12 chromosomes to study allelic variation at genome-wide SSR loci. The geographical diverse origin of parents is reflected in genotypic variations in terms of polymorphism. Out of 1013 whole genome wide SSR markers screened, 294 were found to be polymorphic which resulted in 29.02% polymorphism between the two parents. The highest polymorphism was observed with chromosome 4 (40.96%) whereas the lowest polymorphism was observed in chromosome 9 (16%). Based on the outcomes of the present study, a set of genome-wide polymorphic SSRs will be selected for genotyping of mapping population, preparation of linkage map and QTL analysis for high grain zinc content, iron content, grain quality and yield traits.

Aim: The knowledge of genetic diversity and relationship among the genotypes play a significant role for genetic enhancement in breeding programmes to increase production, improve quality, biotic and abiotic stresses, and also for the selection of superior parental lines in rice. The present field experiment was conducted to study the diversity present in 29 local genotypes of rice using both morphological and molecular ways. Methodology: The experiment was conducted at Agricultural Research Farm, Banaras Hindu University, during Kharif-2017 in an augmented block design with 29 rice genotypes including 3 checks. Mahalanobis’ D2 analysis was carried out to assess the morphological diversity present among the genotypes and molecular analysis was done with 21 polymorphic SSR markers using the NTSYSpc software. Results: Mahalanobis’ D2 grouped the 29 genotypes into 6 clusters based on the inter-se genetic distance. The highest intra-cluster distance was recorded in the Cluster I (32.73), which comprised of 7 genotypes. The highest inter-cluster distance (65.86) was observed between Clusters IV and V. Molecular diversity analysis grouped the 29 rice genotypes into 2 main clusters i.e. cluster I and cluster II with dissimilarity coefficient of 0.34, which were further divided into sub-clusters. Polymorphic Information Content (PIC) value is an evidence of diversity and frequency among the varieties. The level of polymorphism varied from 0.164 to 0.694, with an average 0.521. The highest PIC value was observed for locus RM 5 (0.694) followed by RM 510 (0.692). All the 21 primers showed polymorphism and the number of alleles ranged from 2 to 4 with an average of 3.04.  Conclusion: This study established the presence of considerable amount of genetic diversity among the genotypes studied, the most diverse genotypes being Anupam gold and HUR-1309 followed by Kalanamak-2 and HUR-1304. Breeders may attempt hybridization among the above genotypes which showed maximum diversity, for creating more variability in rice and can be used for planning further breeding programmes.