用PCR技术诊断水稻的白叶枯病抗性  

A PCR Marker-based Selection for Resistance to Bacterial Blight in Rice

作　　者：陆朝福 李晓兵[1] 朱立煌[1] 章琦[1] 杨文才[1] 赵炳宇[1] 王春莲[1] 

机构地区：[1]中国科学院遗传研究所,中国农业科学院作物育种栽培研究所

出　　处：《Acta Genetica Sinica》1996年第2期110-116,共7页

摘　　要：植物育种中应用分子标记辅助选择要求分子标记与目的基因紧密连锁，而且分析手段经济简便、重复性好。Ｘａ２１是最近发现的一个具有广谱抗性的水稻白叶枯病抗性基因，利用一个含Ｘａ２１基因的品系ＩＲＢＢ２１分别与２个感病品种杂交获得２个Ｆ_２群体。用４对引物分别对３个亲本进行ＰＣＲ分析，其中一对引物（ＰＢ７８）的ＰＣＲ产物在抗、感病品种间可揭示多态性。对２个Ｆ_２群体进一步的遗传分析表明，ＰＣＲ标记和Ｘａ２１的白叶枯病抗性紧密连锁，其重组率仅为２．４８％。根据该标记选择基因型纯合的抗性植株，其准确率可达１００％。本文还就植物育种中分子标记的检测途径进行了评价。Molecular marker-based selection in plant breeding requires not only suitable molecular markers closely linked to the known genes,but a simple,economic and reliable analyzing technique.We report here a useful PCR marker for genetic diagnostics in breeding for resistance to rice bacterial blight.Xa21 is a newly found gene of rice which confers resistance to bacterial blight caused by Xanthomonas oryzae pv.oryzae.We produced two F2 populations between one resistant line IRBB21 containing Xa21 and two susceptible varieties,respectively.One PCR marker,PB78,detected polymorphism between the susceptible varieties and the resistant line.Cosegregation between Xa21 and PB78 was studied in the two F_2 populations.The results showed that Xa21 was closely linked to the molecular marker,the crossing over value was 2.48%.Marker-based selection revealed that 100% of the plants with homozygous resistant genotype of PB78 showed resistance to bacterial blight.The available approaches detecting molecular markers in plant breeding are also discussed.

关 键 词：水稻 白叶枯病 抗病育种 聚合酶链反应 抗病性 

分 类 号：S511.103.4[农业科学—作物学]