Combining Ability, Heterosis and Potence Ratio for Yield and Yield Components in Korean Double-Haploid, Progenies and Improved Rice Varieties in Nigeria

Rice is the most widely consumed staple crop in Africa and consumption continues to grow at a rapid pace with increasing population. Success in breeding programs are largely dependent on the genetic diversity of a crop. Genetic variability occurs due to genetic differences in individuals within a given population, which is the basis of plant breeding. Thus, if the genetic variability is well managed, diversity can result to permanent gains in the performance of the crop. The objectives of this study were to determine the interaction between grain yield and yield components and to conduct genetic studies on selected rice genotypes. The research was carried out at the University of Port Harcourt Faculty of Agriculture teaching and research farm. Thirteen (13) varieties were used which comprised 7 adapted Nigerian varieties and 6 Korean rice varieties in a randomized complete block design (RCBD) in three replications was established. All agronomic practices were carried out at appropriately crop phenology. North Carolina II mating design was used to perform crosses. Data was collected on 10 agronomic traits. All means were subjected to ANOVA, combining ability, Heterosis and Potence ratio were determined. The progenies from UPIA 2 x UPN 234, FARO 52 X UPN 266 and UPIA 3 X UPN 266 had the best phenotypic and genotypic expression and most of the hybrids had heterotic values than their parents. The results also showed ranges of dominance for genotypes. UPIA 1, UPIA 2, UPN 223, UPN 234 and UPN266 should be included in breeding programs because they showed the best GCA’s across most traits.