云南高原粳稻抗白叶枯病新品系云资抗21号的选育

以高产优质的云南高原粳稻品种滇系4号为轮回亲本，以IRBB21为白叶枯病抗性基因Xa21的供体亲本，通过杂交和3次回交以及5次自交形成BC3F，代材料，并结合后代材料的白叶枯病抗性鉴定及农艺性状的评价选择，选育出高原粳稻新品系云资抗21号，对云资抗21号的21个单株采用与Xa21连锁标记RM21和RM229、以及22个独立分离的SSR标记进行检测，结果表明这21个单株在RM21位点上均为IRBB21的纯合基因型，在RM229位点上有1个单株显示为轮回亲本的纯合基因型，其余的20个单株均为IRBB21的纯合基因型，而在其余22个SSR标记位点上均显示为轮回亲本的纯合基因型。该新品系白叶枯病抗性与IRBB21相近，农艺性状与轮回亲本相似，具有很好的应用前景。

Breeding of a New Japonica Rice Line Yunzikang 21 for Resistance to Bacterial Blight in Yunnan Plateau

Dianxi 4 was used as recurrent parent while IRBB21 as a gene donor Xa21 resistance to bacterial blight. A new Japonica line named as Yunzikang 21 was b red out from a progeny of BC3F5 through evaluation for resistence to bacterial b light and agronomic traits. 21 single plants of Yunzikang 21 were tested with 24 simple sequence repeat (SSR) markers, RM21 and RM229 link to the gene Xa21 on c hromosome 11 while of the rest separate from the Xa21. The results showed that Y unzikang 21 was similar to IRBB21 in resistance to bacterial blight while it was similar to dianxi 4 in performance of main other characteristics. All the 21 di fferent plants of Yunzikang 21 were homozygous for IRBB21 on the locus of RM21 w hile of 20 ones homozygous for IRBB21 on the locus of RM229. As for the 22 other markers, 21 plants were homozygous for Dianxi 4. The line Yunzikang 21 shows gr eat prospect of application.