Investigation and Research on the Dynamic Occurrence of Major Crop Diseases and Pests and the Succession of Control Strategy in China During 2015-2019

【Objective】 To investigate the dominant types of pests and diseases in various cotton producing areas in China, analyze the occurrence of pests over the past years and the succession of prevention and control strategies, summarize the current green prevention and control technology models of pests and diseases in cotton fields and study future cotton pests and diseases’ prevention and control strategies. 【Methods】 NATESC collected annual data through the cotton disease and insect pest monitoring network by the agricultural technicians in the cotton production area according to the national standardized cotton disease and insect pest survey method. The contents of the survey included the cotton plantating area, occurrence area, the area of control of major cotton diseases and insect pests, the recovery loss and the actual loss, etc., as well as the data of the spray varieties and dosage changes over the years. By comparing the annual average planting area and the area of plant diseases and insect pests, we analysed the succession of diseases and insect pests. Based on the annual succession situation, the distribution changes in different provinces, and the comparison of pests/control, the data of diseases and insect pests and control in China's cotton field production were analysed and evaluated. 【Results】 The results found that from 2015 to 2019, the overall occurrence and control area of cotton diseases and insect pests across the country showed a downward trend which was positively related to planting areas, and the average annual overall control area was higher than that of the occurrence area. The top three areas where cotton diseases and insect pests occurred during the five-year period were Xinjiang, Hebei and Shandong. In 5 years, the average occurrence area of pests was 7.66 million hectares, and the average annual total disease occurrence area was 1.64 million hectares. The average annual control area of cotton pests in 5 years was 9.33 million hectares, and the average annual disease control was 1.63 million hectares. Cotton seedling disease, boll disease, fusarium wilt and verticillium wilt had the highest average annual occurrence area among the diseases. The average annual occurrence area was between 29,019×10 ³ and 511,410×10 ³ hectares. Among the seedling diseases, the area of wilt disease was the highest, with 253,69×10 ³ hectares. Among the pests, the highest average annual incidence area was cotton aphid, cotton bollworm, cotton spider mite, cotton mirid bug, white fly and cotton thrips. The average annual incidence area was 443,81×10 ³ to 2,081,04×10 ³ hectares. The annual occurrence trends of major diseases and insect pests had regional similarities. 【Conclusion】 The actual average annual loss of cotton production throughout the country has stabilized, while the area of control of several major pests is still significantly higher than the area of occurrence, indicating that the pesticide application methods in the control of cotton diseases and insect pests can still be optimized. The succession of the occurrence of cotton diseases and insect pests is the joint result of agricultural pattern, farming system, management technology and ecological environment.