2019年我国草地贪夜蛾扩散为害规律观测

草地贪夜蛾Spodoptera frugiperda(J.E.Smith)侵入我国后呈现快速蔓延为害态势,对我国玉米安全生产造成较大威胁。本文通过全国范围的系统监测,总结了2019年我国草地贪夜蛾侵入扩散区域、为害作物种类、发生面积、发生时间、虫口密度和为害情况。监测结果显示,玉米是我国草地贪夜蛾为害最重的作物。草地贪夜蛾在长江以南地区普遍发生,发生区域由南至北逐步扩散,虫口密度由南至北逐步递减,发生时间西部早于东部,虫口密度西部大于东部。缅甸是我国2019年重要的虫源地,未来应加强对缅甸、泰国和越南等东南亚国家虫源的监测;我国热带和南亚热带存在冬繁区,应尽快摸清其区域和面积;分析了草地贪夜蛾在我国可能发生的代次,提出南方春玉米的种植对草地贪夜蛾起到诱集作用,可延缓或减轻其北迁的时间和虫量,因此,应重视我国玉米品种和种植方式的合理布局,实现对草地贪夜蛾的长期有效治理。

Observation on law of diffusion damage of Spodoptera frugiperda in China in 2019

After the invasion of Spodoptera frugiperda (J.E.Smith) in China, it spread rapidly and threatened the safety of maize production in China. This paper summarized the spreading regions, crop species damaged, occurrence area, occurrence time, population density and damage situation of S. frugiperda in China in 2019 through systematic monitoring nationwide. The monitoring results showed that maize was the most favorite crop of S. frugiperda in China. The occurrence regions of S. frugiperda were widely spread in the south of the Yangtze River. The population density gradually decreased from south to north. It occurred earlier in the west than in the east, and the population density in the west was higher than that in the east. Burma is an important source of S. frugiperda in China in 2019. In the near future, monitoring of the pest in Southeast Asian countries such as Burma, Thailand and Vietnam should be strengthened. There are winter breeding areas in tropical and subtropical areas of China. We should find out its regions and area as soon as possible. The generation number of S. frugiperda in China was analyzed. The planting of spring maize in southern China was suggested, which could induce damage degree in north region, delay the the date and reduce the amount that spread to the north China. In summary, we should put more attention to the rational distribution of maize varieties and planting modes to achieve long-term effective control of S. frugiperda.