Combining Ability and Heterosis of Thai R Lines in Three–Line Hybrid Rice System

Abstract

Development of restorer line (R line) for male parent in three–line hybrid rice system production must be tested combining ability of the developed lines. The objectives of this study were to test combining ability of Thai R lines and evaluate hybrid rice in hybrid rice. Testcross method was used to develop testcross progenies. All entries were grown in randomized complete block design with three replications. Results revealed that R line had the potential to be male parent. Seven hybrids were standard heterosis (RDH3) more than 15%. Hybrids derived from crosses between HCSA/KU1–48–7R gave the highest yield 58.23 gram per plant and higher than check variety 94.10%. Therefore, this cross have high yield potential and appropriate for hybrid rice development.