Forecast of generation trend of maize borer

Release time: 2023-06-19

      According to the results of the post-winter baseline survey of spring corn borer, the number of 100 stalk live insects in most areas of this year was lower than that of the usual year and last year. Combined with the comprehensive analysis of meteorological conditions and other factors, it is expected that the first-generation corn borer will occur moderately in some parts of Northeast China, Huang-Huai-hai and Southwest China, and slightly less in other areas.1亿亩。

      1. The average number of 100 culm live insects of corn borer was low in most areas

      According to the culm stripping survey in spring, the source base of maize borer after winter was lower than that of regular year and last year in most areas, which continued the trend of annual decline in recent years。The average number of living insects was 25 in Jiangsu, Liaoning and Hebei respectively.6头、20.8, 20, 10-20 in Heilongjiang, Jilin, Inner Mongolia, Tianjin, Shanxi, Shaanxi, Shandong and Henan, and less than 10 in other provinces (see Table 1)。

      Table 1 Statistical table of the average number of 100 culm living insects of corn borer in different places

      2. Corn planting and growth had no adverse effects on the occurrence of corn borer

      At present, spring corn is mostly in seedling stage in north China, jointing stage in southwest China, and from jointing stage to tasseling stage in South China and South China.Most of the spring corn in the main producing areas grew well and had no adverse effect on the occurrence and damage of corn borer。

      Third, the weather conditions are conducive to the occurrence of the first generation of corn borer in the rainy areas of South China, and have an inhibitory effect on the occurrence of high temperature areas of North China

      According to the National Climate Center，Mid to late June，Most of Jiangnan, South China, southern Guizhou, most of Yunnan, southeast Tibet and other places accumulated precipitation is 4 ~ 80% more than the same period of the year，Partial more than 1 times，It is beneficial to the generation of corn borer.Most of Inner Mongolia, eastern North China, northern Henan, northern Shandong, northern Jiangsu and Anhui, western Liaoning, southern Xinjiang basin and other places will have daily maximum temperature above 35℃ high temperature weather process，The daily maximum temperature in some areas exceeded 37℃，The occurrence of the first generation corn borer was inhibited by high temperature。

      (Source: Pest Survey Office)