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1984—85两年,进行了大白菜不同地膜覆盖和不同播期的两因子裂区试验。两种地膜覆盖种植的避蚜防病效果是显著的,按有翅蚜总蚜量计算,避蚜效果为57.5—68.7％;按蚜害指数计算,减轻蚜害44.6—47.5％;按病毒病发病率计算,防病效果为74.5—85.1％;有翅蚜迁入大白菜田间的高峰期是在9月中旬到10月中旬。在扬州市郊推迟大白菜播期不能避开蚜虫迁飞高峰。地膜覆盖种植的大白菜可较露地种植的减少药剂治蚜3—4次。
1984-85 two years, carried out a Chinese cabbage different mulching and different sowing two-factor split test. According to the aphid infestation index, the aphid infestation rate was reduced by 44.6-47.5%. According to the virus disease The incidence rate of disease control was 74.5-85.1%. The peak period of winged aphids moving into Chinese cabbage field was from mid-September to mid-October. In the suburbs of Yangzhou delayed sowing cabbage can not avoid the aphid migration peak. Covering the cultivation of Chinese cabbage can be more open-planted to reduce the drug treatment of aphids 3-4 times.