利用有效穗优异配合力分子标记改良粳稻恢复系的效果研究

Effects of Using Molecular Marker of High Combining Ability in Productive Panicle on Improving Japonica Restorer Line in Rice

亲本性状配合力改良是提高水稻杂种优势水平的重要环节。利用粳稻恢复系武育粳3号R的单株有效穗数优异配合力标记RM208-180条带,以武育粳3号R为供体亲本,宁恢8号为受体亲本,通过SSR分子标记辅助选择的杂交、回交和自交,获得了RM208位点为180 bp纯合条带的宁恢8号遗传背景的改良恢复系4个。改良恢复系8010-4-10、8010-4-14和8012-2-9分别与BT型雄性不育系863A配组,3个杂交组合单株有效穗数均显著高于对照宁恢8号,分别提高65.5%,56.9%和86.2%。3个组合的生育期和株高与对照差异不显著而单株有效穗数、单株日产量和单株产量显著增加,表明在不育系相同的条件下,改良的恢复系在目标性状的配合力上得到了明显改良。

Improvement of combining ability in traits of parents is an important strategy for enhancing heterosis level in rice. Using japonica restorer line Wuyujing 3 R as the donor parent for RM208-180 band with high combining ability in productive panicle and Ninghui 8 as the receptor parent in japonica rice, four improved restorer lines with the homozygous 180 bp band at RM208 site and the genetic background ofNinghui 8 were obtained through crossing, backcrossing, selfing and the SSR molecular marker-assisted selection technique based on the information of high combining ability in the number of productive panicles per plant of the band of SSR marker RM208-180. Among four F1 hybrids derived from the improved restorer lines and the BT-type CMS line 863 A, three hybrids, namely, 863A/8010-4-10, 863A/8010-4-14 and 863A/8012-2-9, showed a significant increase in the number of productive panicles per plant, compared with that of the check F1 hybrid 863A/Ninghui 8, by 65.5%, 56.9% and 86.2%, respectively. Besides, these three hybrids were not significant different from 863A/Ninghui 8 in whole growth duration and plant height but had significantly higher grain yield per plant and daily grain yield per plant than 863A/Ninghui 8. It is indicated that the combining ability in the target trait of the improved restorer lines has been greatly enhanced when crossed with the same male sterile line.