分子标记辅助选择改良杂交水稻金优207的白叶枯病抗性

摘要

Two bacterial blight resistant varieties,Huahui 20 carrying Xa7 and Xa21 and CBB23 carrying Xa23 as donor parents were crossed with the male parent of hybrid rice Jinyou 207 as receptor parent.Nine bred lines carrying Xa7,Xa21,Xa23,Xa7 + Xa21,Xa7 + Xa23,respectively,under the genetic background of Xianhui 207 were selected by backcrossing,multicrossing and molecular marker-assisted selection and pyramiding.Seven strains of Xanthomonas oryzae pv.oryzae,PXO61,PXO99,ZHE173,GD1358,FuJ,YN24 and HeN11 were inoculated to the nine bred lines and their hybrid combinations with Jin 23A as female parent for identifying the bacterial blight resistances.The results showed that bred lines and hybrid combinations carrying Xa7 gene were resistant to five Xoo strains,PXO61,ZHE173,GD1358,YN24 and FuJ.The bred line and their hybrid combination carrying Xa21 gene were resistant to six Xoo strains,PXO61,PXO99,ZHE173,GD1358,YN24 and FuJ.The bred lines and their hybrid combinations carrying Xa23,Xa7 + Xa21,Xa7 + Xa23 genes were resistant to all of the seven Xoo strains.The results showed that yield trials,main agronomic traits and rice quality of the two combinations,Jin 23A/CY10012-2 (carrying Xa7,resistance to five Xoo strains) and Jin 23A/CY10004-7 (carrying Xa7 and Xa21,resistant to seven Xoo strains) were similar to Jinyou 207.It can be concluded that these two combinations could replace Jinyou 207 for rice production of second-cropping in the Yangtze River Valley,which can increase the resistance level to bacterial blight.%以先恢207为受体亲本,华恢20(携带Xa7和Xa21基因)和CBB23(携带Xa23基因)为供体亲本,通过杂交、回交、分子标记辅助选择和基因聚合育种,育成了携带Xa7、Xa23、Xa7+ Xa21、Xa7+ Xa23基因的株系各2个,携带Xa21基因的株系1个.用PXO61、PXO99、ZHE173、GD1358、FuJ、YN24及HeN11等7个菌株对这9个育成株系及其与金23A配制的杂交组合进行白叶枯病抗性鉴定,并进行主要农艺性状、产量和稻米品质的比较分析.结果表明,携带Xa7基因的株系和杂交组合抗PXO61、ZHE173、GD1358、YN24、FuJ等5个菌株,携带Xa21基因的株系和组合抗PXO61、PXO99、ZHE173、GD1358、YN24、FuJ等6个菌株,同时携带Xa7和Xa21基因的株系和组合对7个菌株均表现中抗、抗病或高抗,携带Xa23基因和同时携带Xa7和Xa23基因的4个株系和组合抗或高抗7个菌株.初步筛选出1个携带Xa7基因的组合金23A/CY100122、1个同时携带Xa7和Xa21基因的组合金23A/CY10004-7,分别抗5个和7个白叶枯病菌株,且产量、稻米品质和生育期均与金优207相似.以这2个组合作为金优207的替代组合进行生产种植,可以提高长江中下游稻区双季晚籼稻的白叶枯病抗性.