Relationships Between Climate Change And Occurrence Dynamics And Development Of Diseases And Insect Pests In Representative Climate Regions Of Shandong

Climate change will have a big effect on agricultural industry. The characteristics of climate change, the occurrence dynamics and development of crop insect sand diseases and the relationships between them in Feicheng, Gaomi and Wendeng, the representative climate regions of Shandong, were studied in this paper. The influence of evolution tendency of the main climatic factors on the main crop pests and diseases were analyzed. The main conclusions are following:1. Dynamics of climate change in representative climate regions of ShandongThe annual mean temperature all increased in recent50years in these three cities. The fluctuation ranges of annual mean temperature are becoming larger and larger. Seasonal mean temperature rise rate are different, and winter is the fastest. The change tendencys of seasonal and annual precipitation were not obvious, but the precipitation of three cities were very fluctuant.2. The occurrence dynamics and development of crop Diseases and Pests in representative climate regions of ShandongWheat and corn are the main crops in Shandong. Their plantation areas rates are32%and24%.The occurrence area rate of diseases and insect pests in Feicheng trended to increase, while outbreak degree of diseases and pests trended to decrease. The variation trend of occurrence area rate of diseases and outbreak degree of diseases and pests in Gaomi were not obvious, only the occurrence area rate of insect pests reduced obvious. The decrease of outbreak degree of diseases and occurrence area rate of insects were obvious compared with outbreak degree of insects and occurrence area rate of diseases in Wendeng.The occurrence area rate of diseases and insect pests in Feicheng trended to increase, while outbreak degree of diseases and pests trended to decrease. The trends of occurrence area rate of diseases in Gaomi were not obvious, while the outbreak degree of diseases and pests incresed obvious. The decrease of outbreak degree of diseases and occurrence area rate of insects were obvious in Wendeng. The trends of Wheat Sharp Eyespot in three cities was obvious, while Wheat Leaf Rust, Wheat Powdery Mildew and Wheat Aphid were not obvious..The occurrence area rate of diseases and insect pests in Feicheng trended to increase, while outbreak degree of pests trended to decrease. The variation trend of occurrence area rate and outbreak degree of diseases and pests in Gaomi were not obvious. The increase of outbreak degree of insects was obvious in Wendeng.3. The relationships between climate change and occurrence dynamics and development of crop Diseases and PestsThere were no obvious correlations between occurrence area rate of diseases and temperature in Feicheng. Summer temperature, especially minimum temperature affected occurrence area rate mainly in Gaomi. Spring precipitation and spring temperature-precipitation coefficient had positive significance correlation in Wendeng. Outbreak degree of diseasesThere were obvious correlations between outbreak degree of diseases and temperature, especially summer temperature in Feicheng. The relationship between weather factors and occurrence area rate of diseases is not evident in Gaomi. Spring temperature and winter temperature-precipitation coefficient affected outbreak degree of diseases mainly in Wendeng.Winter minimum temperature and occurrence area rate of pests had positive significance correlation in Feicheng. The relationship between weather factors and occurrence area rate of pests is not evident in Gaomi. Occurrence area rate of pests was affected mainly by spring extreme temperature and winter temperature-precipitation in Wendeng.Spring temperature and outbreak degree of pests had negative significance correlation in Feicheng. Autumn temperature and outbreak degree of pests had positive significance correlation, while annual precipitation and temperature-precipitation coefficient had negative significance correlation in Gaomi. Spring precipitation and temperature-precipitation coefficient were significantly negatively related to outbreak degree of pests in Wendeng.Spring minimum temperature had been the biggest influence on outbreak degree of Wheat Sharp Eyespot. Less precipitation and high temperature in winter, less precipitation and low temperature were beneficial to spread of disease. Temperature had a far greater effect on outbreak degree than precipitation. The low temperature in winter was good for disease to produce.The3rd generation of Cotton Bollworm adults occured more earlier, last stage of2nd,3rd and4th generation adult indicate advance trends, the developmental duration of the2nd and4th generation adult were getting shorter. Temperature and occurrence period showed negative correlation. Temperature factor has long and sustainability effect on the first three generations at whole spring and summer. Effects of precipitation were shorter and directed towards months of cotton bollworm. The influence of temperature on occurrence period was bigger than precipitation. The overwintering pupae, the one generation and the four generation of adults occur showed the decreasing trend, the two and three generation adult moth changed more stable. In March the average of temperature and precipitation as well as the highest temperature could affect the number of overwintering pupae. Temperature and precipitation had aftereffect on the amount of all pupae. Contemporary of temperature and precipitation could behindhand influence the number of next generation.