Abstract: A polypeptide from rice cultivar IR26, IR1545, or TN1 interacts with incompatible (avirulent) strains of Xanthomonas campestris pv. oryzae (Xco) but not with compatible (virulent) ones. A polypeptide from Nangeng 15 has been found which disappeared from the 2-D slabs after mixing with incompatible Xco strains. Nangeng 15 displays resistance in adult period but not in seedlings. The polypeptide was found in adult period but not in the seedling stage. IR26 is a resistant cultivar in the full growth period, it expresses the polypeptide not only in adult period but also in seedlings. According to genetic analyses, the resistance of cultivar DV85 to bacterial is controlled by three genes (Xa-5, Xa-6, and Xa-7). We have not gotten the Xco strain matched for Xa-6, the data showed merely that rice cultivar DV85 expresses more than two kinds of strain-specific polypeptide of different specificity. The phenomenon may provide evidence for Ellingboe's model of incompatible combination. As the strain-specificity and the temporal expression patterns of the polypeptides are correlated with the cultivar resistance in field, the polypeptides might be the products of the resistant genes.

Key words: Gene, Gene complementarity, Recognition polypeptide, Oryza sativa, Xanthomonas campestris pv. oryzae

摘要： 经蛋白质双向电泳分析，发现水稻IR26、IR1545及TN1各有一个多肽能与不亲和的白叶枯病菌株产生特异性作用而消失，但与亲和菌株相互不发生作用。成株期抗病品种南粳l5在成株期有与不亲和菌株作用的多肽存在．而在苗期则未观察到这一多肽。对全期抗病品种IR26分析表明，它无论在成株期还是苗期均出现一个与不亲和菌株专一作用的多肽。经典遗传学分析认为有三个抗白叶枯病基因的DV85，则观察到DV85有两个以上的菌株特异性多肽。由于选些多肽表现出菌株的专一性及其它表达生理时期均与该品种的田间抗病表型一致，同时多肽的数目也与经典遗传学分析结果类似，推测这些多肽可能是抗病基因的产物。

关键词: 白叶枯病, 水稻, 多肽, 基因互补性, 基因产物