Studies on Genetic Variability and Divergence for some metric traits in low land rice with tolerance to submergence and stagnant flooding

Genetic variability and divergence were studied for yield and yield related traits in fifty one elite low land rice cultures, selected on the basis of their tolerance to situations like submergence and stagnant flooding. The experimental materials possessed considerable amount of variability for all the traits. Majority of the traits showed smaller difference between phenotypic coefficient of variation and genotypic coefficient of variation. Both GCV and PCV were high for number of fertile grains / panicle, 100-grain weight, harvest index, grain yield / plant and plot yield while, high heritability with moderate to high genetic gain for days to 50 % flowering, plant height, number of fertile grains / panicle, 100-grain weight, harvest index and plot yield indicating the presence of additive gene effect. The test genotypes were grouped into twelve clusters, where Cluster I and Cluster II were the largest accommodating ten genotypes. Maxim minter-cluster distance was noticed between the clusters VIII and XI, which could be used for recombination breeding to throw some transgressive segregants for varietal improvement. Days to 50 % flowering and plant height contributed maximum to genetic diversity.