中文摘要：

由Phytophthora infestans引起的晚疫病是马铃薯的毁灭性病害。明确现有马铃薯品种或育种材料含有的晚疫病抗病基因，对于抗病育种和合理利用不同抗病基因防治马铃薯晚疫病具有重要意义。根据“基因对基因”学说，马铃薯无毒基因与抗病基因产物互作会产生典型过敏反应（HR）。理论上利用病原菌无毒基因可以鉴定马铃薯是否含有相应抗病基因。本研究尝试利用农杆菌注射技术，在马铃薯叶片中瞬时表达晚疫病菌无毒基因（Avr），根据过敏反应发生情况，进而推断马铃薯品种/育种材料所含相应抗病基因（R）。研究结果显示：适合马铃薯瞬时表达的农杆菌浓度为0.5（OD600），马铃薯材料农杆菌瞬时表达存在明显的基因型和叶龄依赖性，充分展开的幼嫩叶片适合农杆菌瞬时表达。Avr1, Avr2, Avr3a和Avr4在含有相应抗病基因的马铃薯鉴别寄主上瞬时表达能够产生HR，表明无毒基因注射鉴定结果是可靠的。无毒基因注射鉴定结果与抗病基因特异引物PCR扩增结果在不同基因型材料上有时并不一致，反映了这两种方法各有局限性，若能将这两种方法结合使用，则会提高鉴定结果的准确性。

英文摘要：

Late blight, caused by Phytophthora infestans, is a devastating disease of potato. It is important to distinguish what kind of R contained in potato cultivar or potato breeding materials for potato late blight resistant breeding and control late blight through management of different R genes. According to the‘gene-for-gene’hypothesis, the interaction between pathogen avirulence genes（Avr）and resistant genes（R）wil lead to hypersensitive response（HR）in potato. So, it is possible to distinguish host R gene by Avr gene expression in potato leaves. In this study, efforts were made to distinguish potato R genes by transient expressing P. infestans Avr gene in potato leaves using agro-infiltration methods. The result revealed that 0.5 optical density at 600 （OD600） was suitable for potato agro-infiltration. Agro-infiltration mediated Avr expression efficiency depended on potato genotype and leaf age. Ful expanded younger leaves were fit for Agro-infiltration mediated transient Avr gene expression. Transient expressing Avr1, Avr2, Avr3a and Avr4 in leaves of diagnose potato material which contains corresponding R genes led to HR. Identification results of both agro-infiltration method and R gene specific primers PCR amplification were not consistent in some potato genotypes, reflecting that both methods have some defects. The desirable results could be obtained by combining the two methods.