马铃薯晚疫病(Potato Late Blight)是发生最普遍、最严重的病害(图1),既造成茎叶枯斑和枯死,又可引起田间和贮藏期间的块茎腐烂,一旦发生并蔓延,会造成非常严重的损失,轻者减产30%~40%,重者减产可达70%~80%。发病症状马铃薯的根、茎、叶、花、果、匍匐茎和块茎都可发生晚疫病,最直观最容易判断的症状是叶片和块茎上的病斑。 Potato Late Blight is the most common and serious disease (Figure 1). It not only causes stem-leaf blight and withering, but also causes tubers to rot during the field and during storage. Once it occurs and spreads, it can cause extremely Serious losses, light output reduction of 30% to 40%, heavy output reduction of up to 70% to 80%. Disease symptoms Potato roots, stems, leaves, flowers, fruit, stolons and tubers can occur late blight, the most intuitive and easy to determine the symptoms of the leaves and tubers on the spot.