Heterosis and Restoring Ability of Some Cytoplasmic Male Sterile and Suggested Restorer Rice Lines

THE PRESENT investigation was conducted at the Experimental Farm of Faculty of Agriculture, Kafrelsheikh University, Egypt during 2011 and 2012 seasons. Four cytoplasmic male sterile (CMS) lines having different cytoplasmic source, namely G46A, D297A, Yimi15A and V20A beside ten male parents and their forty F₁ hybrids as well as the iso genic maintainers of the CMS lines were the materials of this study. Sakha 105, Sakha 106 and Sakha 101 rice cultivars were identified as good maintainers for the CMS lines G46A and D297A. Contrary, Giza 182, Giza 178, Giza 181and Wita 12 were identified as good restorers for the two previous CMS lines and V20A. Most of the combinations showed either partial restorers or partial maintainers. The CMS lines G46A and D297A were easy to restore and the opposite was true for the CMS line Yimi 15A as it has japonica type which is difficult to restore. D297A x Giza 182, V20A x Giza 178 and G46A x Giza 178 were the best combinations for grain yield (high heterobeltiosis values). D297A x Giza 178 and D297A x Gz.1368 were promising hybrids for recombination breeding for grain yield, V20A x IET1444 for number of panicles/ plant, while Yimi15A x Sakha 106 and Yimi15A x Sakha 105 were promising hybrids for recombination breeding for early heading.