Abstract:
The wheat wireworm is an important underground pest in the dry farming area of northern China. In recent years, large-scale implementation of conservation tillage measures and crop straw crushing in North China, the winter wheat and summer corn are planted in two crops per year, creating a favorable environment for feeding and habituating for the golden worm. The temperature in autumn, winter and spring of Gucheng Station in Hebei Province from 2018 to 2019 showed a phenomenon of low temperature and high temperature alternating between cold and warm, especially the minimum temperature is significantly higher, inducing the explosive occurrence of the golden worm in the wheat field. According to the investigation of spring wheat field excavation, the maximum density of insect population is 144 heads/m
2, the maximum weight of insect population is 18.764g/m
2. In 58 investigation points, the control index was 5 heads /m
2, accounting for 98.27%. The density of insects in the jointing-harvest period was the highest during the booting period, followed by the jointing period, and the lowest in the harvest period. The oldest larvae have a maximum length of 34.68 mm, and a maximum width of 4.9mm, the longest growth is 4.68 mm and the widest is 0.90 mm. The density of insect populations in the continuous cropping winter wheat + summer maize gramineous crops was 35.3 to 40.4 heads / m
2, which was significantly higher than that of soybean, corn, and winter wheat recreation grounds, and the peanut and spring corn lands were more than 5 times higher than the soybean insect population density, the weight of insect population was more than 10 times higher. Yield measurement in mature wheat fields: grain yield reduced by 36.8%, insect population density increased by 10 heads / m
2, grain yield decreased by 4.824%, insect population weight increased by 1g / m
2, grain decreased yield increased by 3.871%, plant pest increased by 10% and grain yield decreased by 11.587%.