Changes of eco-environment of farmland and development of some crops diseases and insect pests

Based on long-term statistical data provided by specific department in Xinxiang region of Henan province,it is showed that the main factors related with agricultural eco-environment have changed greatly in recent decades.For example,annual sunshine hours and annual average wind speed decreased gradually,while the relative humidity increased slowly with time,which caused regional decrease of evaporation from water surface.Moreover,some plant diseases and insect pests are becoming more serious than ever owing to the changed meteorological factors,the development of irrigation system and the increased N application rate.Effective measurements for lessening the danger of plant diseases and insect pests are to establish water-saving agriculture and economic fertilization systems and to evolve new varieties with high pest resistance.