Abstract: WFZ (Wufengzhan 2) and IRBB5, with minor-polygene and a major gene xa5 resistant to bacterial blight respectively, were used as parental lines to pyramid minor-polygene and major genes by using marker assisted-selection, anther culture and backcross. The new piece of R primer, 5′CCAGACACCACTGCACATTC 3′, was designed according to the sequence of RG556 in GeneBank using Primer 3, the new R primer has a similar _^Tm to the F primer. The PCR efficiency of amplification was greatly improved, about ten times higher than those of the old ones. The individual of B₁F₁ derived from WFZ 2/IRBB5 showing similar lesion length to WFZ and with gene xa5 were selected for anther culture, sixteen of 30 diploid lines with xa5 incorporated were obtained. These lines showed a higher level of resistance than both of their parents with only 0.1 cm lesion in length. The result showed that the minor-polygene and the major gene were successfully pyramided. It took only two years from the cross to the pyramid, about 1-2 years less than that of the traditional breeding method.

Key words: bacterial blight, resistance gene, maker assisted-selection, anther culture, gene pyramiding

摘要： 以受微效多基因控制白叶枯病抗性的五丰占2号和主基因[i]xa5[/i]控制的IRBB5为材料，应用分子标记辅助选择、花药培养和回交技术研究了主基因与微效多基因聚合的途径。经查阅GeneBank中RG556的序列，利用在线引物设计软件Primer 3设计了一条新的R引物：5′CCAGACACCACTGCACATTC3′，克服了原引物Tm值相差太大，扩增效率低的缺点，使PCR扩增效率提高了近10倍。采用病斑长度与五丰占2号相近且携有xa5基因的五丰占2号[sup]2[/sup]/IRBB5 B[sub]1[/sub]F[sub]1[/sub]植株进行花药培养，获得30株二倍体植株，其中16株携有[i]xa5[/i]基因。携有[i]xa5[/i]基因的植株的平均病斑长度仅0.1 cm，对白叶枯病的抗性明显强于双亲。成功地聚合了白叶枯病抗性主基因和微效多基因。从配组到获得主基因和微效多基因聚合材料仅用两年时间，比常规育种方法缩短1~2年。

关键词: 白叶枯病, 抗性基因, 分子标记辅助选择, 花药培养, 基因聚合