Assessment of genetic diversity of aromatic rices (Oryza sativa L.) using morphological, physiochemical and SSR markers

Genetic diversity of a set of 50 elite rice genotypes was assessed through morphological, quality and SSR markers. The mean values for agro-morphological and quality characters were found to be highly significant. Plant height was found to be significantly associated with days to 50 per cent flowering and maturity. Kernel length was found to have highly significant positive correlation with cooked kernel length (CKL), cooked kernel breadth (CKB), gelatinization temperature (GT) and length to breadth (L/B) ratio while GT was found be have significant negative correlation with alkali spread value (AS) and positive correlation with CKL and L/B. Cluster analysis using morphological and physiochemical traits revealed five and three major clusters, respectively. Euclidian distance ranged from 0.39 to 24.30 per cent and 0.4 to 5.44 per cent, respectively for morphological and quality traits. SSR marker analysis revealed distinct polymorphism among the cultivars with 28 primers and the polymorphic information content (PIC) value ranged from 0.139–0.99 with an average of 0.589 per primer. UPGMA Cluster analysis grouped the rice genotypes into eight clusters in which the genotypes that are derivatives of genetically similar type clustered together. Principal coordinate analysis carried out to visualize genetic relationship among elite genotypes revealed results similar to those of UPGMA results. The study revealed that cluster analysis for related cultivars as revealed by morphological, physiochemical and microsatellites markers provides greater confidence for the assessment of genetic diversity and relationships, which could be used in subsequent breeding programs.