野生稻增产QTL导入9311之近等基因系的构建

以超级杂交中稻恢复系9311为受体和轮回亲本,马来西亚普通野生稻(O.rufipogon)为增产QTL yld1.1和yld2.1的供体进行杂交和连续回交,各世代采用分子标记辅助选择,至BC6F1后自交,得到BC6F2群体,通过分子标记检测,获得分别携带野生稻增产QTL yld1.1、yld2.1及同时携带yld1.1和yld2.1的3套近等基因系.对同时携带yld1.1和yld2.1的近等基因系进行遗传背景分析,发现其与受体9311的遗传组成有93.9%一致.田间试验表明,野生稻增产QTL近等基因系的产量均高于受体,说明将野生稻增产QTL转移至杂交稻恢复系中,能提高其产量水平,且2个QTL的增产效果大于单个QTL的效果.

Development of Near-isogenic Lines with Yield-enhancing Genes from O.rufipogon by MAS in 9311

Using 9311,a restorer line of two-line super-hybrid rice,as the recipient and recurrent parent and Oryza rufipogon as the donor of two yield-enhancing QTL alleles,yld1.1 and yld2.1 on chromosomes 1 and 2, respectively,three types of near-isogenic lines(NILs) containing yld1.1 and yld2.1 or yld1.1 or yld2.1 were developed by successive backcrossing and molecular marker-assisted selection(MAS).The genetic background of the near-isogenic lines was similar to that of the original parent 9311 at a degree of 93.9%.The NILs with the yield-enhancing QTLs had a higher grain yield than 9311 in the field experiments,which indicates that transferring the yield-enhancing QTLs into the restorer line of hybrid rice can increase its yielding ability.Furthermore,the yield-increasing effect of the NILs with both yld1.1 and yld2.1 was greater than that of the NILs with only a single QTL allele yld1.1 or yld2.1.