Genetic variability and association analysis in rice (Oryza sativa L.) germplasm based on biometrical and floral traits

The present experiment was carried out to evaluate 150 rice germplasm accessions for biometrical and floral traits to assess the amount of variability and association among them. Eight biometrical and thirteen floral characters were recorded. Analysis of variance showed that there was a significant variation observed for all the characters studied at a 5% probability level. High PCV and GCV was recorded for spikelet sterility percentage (28.78%, 21.61%), number of pollen grains per anther (22.25%, 21.08%) and pollen load (31.31%, 31.12%). High heritability along with high genetic advance was recorded for all biometrical traits except spikelet sterility percentage and six floral traits viz., stigma length, anther length, style length, apical pore, number of pollen grains per anther and pollen load. Single plant yield showed a positive correlation with thousand grain weight. Mean performance of traits studied indicated that, higher yield per plant was observed in Thilainayagam and a high 1000 grain weight in Sembala. The high number of productive tillers per plant was observed in Kodai. Four genotypes, Thooyamalli, IG 23, IG 24 and Vellai chithiraikar were recorded higher panicle length and the least spikelet sterility percentage was observed in IG 7. Hence, the identified germplasm with distinct biometrical and floral characters could be utilized for further hybridization programme.