Studies on genetic divergence and screening of parental lines for Rf3 and Rf4 genes through molecular markers in hybrid rice (Oryza sativa L.)

Abstract

Sixty four parental lines of hybrid rice were evaluated for genetic divergence by taking into account of nine traits during two seasons of year 2018. By resolving the parental lines into ten groups, Ward’s clustering method demonstrated the parental lines having significant genetic diversity. Cluster X had the most parental lines (13) out of all the clusters, followed by cluster II (12 genotypes). The parental line clusters IX, VIII, VII, V, and IV, which correspond to SD-5, SD-2, HSRV-16, GR-37, and SD-39, respectively, showed the significant degree of variability. Screening for fertility restoration was done in 64 parental lines with the help of SSR molecular markers. Among them, 44 potential restorers were identified (Rf4 and Rf3 present) with a hundred percentage efficiency supported molecular screening. The traits number of productive tillers per plant, length of the panicle and number of grains per panicle were significantly correlated with the trait grain yield per plant. Path analysis showed that the traits number of grains per panicle, the number of productive tillers per plant, test weight and panicle length had positive direct effects on grain yield and indicating that selection for these yield contributing traits could lead to an improvement in single plant yield as a whole.

Keywords

• genetic diversity
• character association
• fertility restoration.