Genetic diversity analysis of parental lines for hybrid development in rice (Oryza sativa L.)

Abstract

Genetic divergence of 40 parental lines comprising 30 restorer and 10 maintainer lines were studied through Mohalanobis's D 2 and principal component analysis for eleven characters. Genotypes were grouped into five different clusters. Cluster V comprised maximum number of genotypes (thirteen) followed by cluster I and II. The inter-cluster distance was maximum between clusters I and V (13.495) indicating wide genetic diversity between these two clusters followed by the distance between cluster I and 11 (9.489), cluster IV, and cluster V (8.969) and cluster I and cluster III (8.039). The minimum inter-cluster distance was observed between cluster II and cluster III (3.034) followed by cluster 111 and cluster IV (3.834) and cluster II and cluster V (4.945) indicating that the genotypes of these clusters were genetically close. The intra cluster distance in the entire five clusters was more or less low which indicated that the genotypes within the same cluster were closely related. Among the characters panicle weight contributed most for divergence in the studied parental lines. Difference in cluster means existed for almost all the characters studied. Highest mean value for number of effective tillers (7.8), days to 50% flowering (95.5), panicles/m 2 (192.6), panicle weight (2.9), spikelet fertility (84.8), number of grains/panicle (177.8), days to maturity (123.6), and grain yield/plot (1065.5) were observed in cluster I indicated the parental lines fallen in this cluster having the genetic potentiality to contribute better for yield maximization of hybrid rice.

Heterosis Studies on Grain Yield and Yield Attributes in Rice (Oryza sativa L.)

“…For [24] reported both significant positive heterobeltiosis and heterosis for this character, as did Chamundeswari et al [27], Utharasu et al [23] and Parimala et al [8], whereas standard heterosis of similar nature was reported by Dar et al [25], Ramesh et al [28], Gokulakrihnan et al, (2018), Manjunath et al [18] and Mohammad, I. [21,[29][30][31][32][33][34][35][36][37].…”

Assessment of Genetic Diversity in New Restorer Lines of Hybrid Rice

“…However with as few as 24 rice varieties, Kunusoth et al, (2015) obtained seven components for 24 traits. Hasan et al, (2012) performed D 2 and PCA analysis in 30 restorer and 10 maintainer lines of rice in which two principal components were derived. In 100 restorer and maintainer lines, 10 clusters were formed in cluster analysis by coefficient of parentage (Wang et al, 2012) of which, the restorer lines further divided into 11 sub clusters.…”

Heterosis studies for grain yield and yield attributes in rice (Oryza sativa. L) hybrids

“…The availability of diverse parental lines and genetic knowledge of a trait are critical factors in the development of heterotic hybrids. By carefully choosing maintainer and restorer lines based on genetic variation, hybrids with greater yield potential than their parents and traditional check types may be produced (Hasan et al, 2012). Before starting any crop improvement programme or utilising the proper selection strategies, it is essential to understand the nature and scope of genetic variation that governs the inheritance of quantitative traits like yield and its components.…”