Abstract:

To further clarify the occurrence of the diseases, insect pests and weeds of winter wheat under the new farming system, the main species, the occurrence characteristics and the change reasons were studied with sampling investigations and questionnaires to farmers in 32 monitoring sites from Piedmont, Heilonggang and Eastern Plains in Heibei Province. The results showed that under the new farming system, the main species of diseases, pests and weeds had reached up to 15, 20 and 21 respectively, and the main diseases and pests were Powdery Mildew, Sharp Eyespot, Scab, Aphids, Wheat-spider and Wheat midge with Descurainia Sophia as the dominant species in all weeds. There were four characteristics about the occurrence of the diseases, insect pests and weeds, including some secondary diseases and insect pests becoming to the dominant, the complex and diverse weeds species, a tendency expanding from the former location to North and East and a continuous damage to wheat and corn. In a word, the occurrence changes of the diseases, insect pests and weeds were mainly caused by the new farming system which was benefit to protect the habitats, improve the cardinal number and accelerate the transmission of the diseases and insect pests in different regions and blocks. In addition, the warming climate and the lack of resistant varieties were also the important factors in the occurrence of diseases and insect pests over the past decade.