甘薯瘟病系由假单胞菌属引起的一种细菌性萎蔫病。病菌可在土壤中长期存活,并从根茎伤口侵入,然后沿着维管束导管向上扩展,引起地上部叶片凋萎,甚至整株枯死。病菌在侵染寄主过程中,常伴随一些腐生菌。在人工培养基上,腐生菌的菌落出现早,生长快,常抑制了病菌的正常生长,从而造成病菌分离上的困难。而且,据维管束病害的侵染特点,常用根部切伤或薯苗剪口接种。尽管此法较接近于自然感染,然而,当地下部根茎已受感染,而地上部茎叶在短期内还难于看出症状。因此, Sweet potato blast is a bacterial wilt disease caused by Pseudomonas. Bacteria can survive long-term in the soil and invade from rhizome wounds, and then expand upward along the vascular bundle catheters, resulting in wilting of shoots in the shoots and even the entire plant is dead. Viruses in the host infection process, often accompanied by some saprophytic bacteria. In artificial media, saprophytic colonies appear early, fast growth, often inhibit the normal growth of bacteria, resulting in the separation of bacteria difficult. Moreover, according to the characteristics of vascular disease infection, commonly used root cutting or potato seedling mouth vaccination. Although this method is closer to natural infection, however, the lower rhizomes in the area are already infected, and the aboveground stems and leaves are hard to detect in short term. therefore,