为了快速准确地鉴定出 3种不同的马铃薯(Solanum tuberosum L.)病原菌，即致病疫霉(Phytophthora infestans)、立枯丝核菌(Rhizoctonia solani)和茄链格孢菌(Alternaria solani)，根据 GenBank中的这 3种病原菌基因序列设计特异引物，从影响多重聚合酶链式反应(PCR)扩增的因素(如退火温度和引物浓度)对反应体系进行优化，建立能够同时检测 3种马铃薯病原菌的多重 PCR方法。结果显示，所建多重 PCR方法的检测限为 40.0 fg/μL，灵敏度较高，且具有良好的特异性。该检测方法实现了同时对 3种马铃薯病原菌的高效、快速的检测，提高了检测效率，降低了检测成本，在马铃薯病害的早期预防、诊断及防控中具有较高的应用潜力。

A multiplex PCR assay was established for rapid and accurate detection of three potato pathogens, Phytoph-thora infestans, Rhizoctonia solani and Alternaria solani. According to the published gene sequences of these three patho-gens in GenBank, we designed 3 pairs of specific primers. The main factors influencing the multiplex PCR efficiency, such as annealing temperature and primer concentration, were optimized. The results showed that our proposed multiplex PCR as-say provided high sensitivity and extraordinary speci.city. The detection limit was estimated to be approximately 40.0 fg/μL. With its high e.ciency, low cost and rapidity, the multiplex PCR assay has great potential application in the early prevention, diagnosis and control of potato diseases.