Genetic Variability Study of some Rice Genotypes (Oryza sativa L.) for Morphological, Yield and Grain Quality Traits

The present investigation aimed to study the genetic diversity among some genotypes of rice in two rice successive seasons 2014 and 2015 at the experimental farm of Sakha research station. Thus, genotypic coefficient of variance (GCV), phenotypic coefficient of variance (PCV), heritability in broad sense (h2) and genetic advance (GA) were determined for all the studied traits. In addition, the nature and magnitude of genetic divergence estimated in 24 rice genotypes using Mahalanobis D2 – statistics by considering 17 quantitative traits. High estimates of GCV and PCV were recorded for panicle excretion%, gelatinization temperature, grain elongation% and amylose content%. Heritability in broad sense was high for all characters under study. High heritability coupled with high genetic advance were recorded for number of filled grains/panicle and plant height traits. Based on genetic distance, the 24 studied genotypes were grouped into 11 clusters. Cluster III was the largest and consisted of five genotypes, followed by cluster X with four genotypes, while clusters VI and XI contained two genotypes for each one. However, clusters I, V, VII, VIII and IX included one genotypes for each one. The highest inter clusters distance (102.605) was between cluster V and XI while, the lowest one was found between cluster II and X (22.017). Principal component analysis revealed that seven quantitative traits (grain length, grain shape, plant height, amylose content%, 1000-grain weight, number of panicles/plant and panicle length) were significantly influenced the variation in these genotypes. Therefore, the present investigation determined the genetic variability in some genotypes that could be used to improve the rice breeding programme with respect studied traits.