Comprehensive soil disinfection technologies to soilborne disease of Chinese yam

摘要

In the production of Chinese yam, continuous cropping would cause the accumulation of insects, nematode eggs or pathogenic bacteria and result in devastating soilborne diseases. These diseases will severely affect crop yield and quality after 3-5 years. Generally, the yield would be reduced by 20%, and sometimes all yields of the entire field would be lost. As the characteristics of long-term perdurability, complexity and popularity to the soilborne diseases occur, there are many scientific and technical problems that need to be examined deeply. After years of experimentation in Qingyuan County, Hebei province, our group has made a few technological breakthroughs in controlling soilborne pests, although some remain unsolved. The main diseases of yamare caused by Pratylenchus and Meloidogyne. The highly efficient and environmentally friendly soil fumigants such as trichloronitromethane, dazomet, dimethyl disulfide, 1,3-dichloropropylene, sulfuryl fluoride, metam, have been selected for controllingthe problems of nematode and soilborne diseases. Novel deep soil disinfection technology and equipment suitable for yam fields have been developed to overcome major difficulties in applying fumigation agents to the deep root layer of 35 cm. Seed disinfection processing technology of seed yams has been also developed to effectively control the spread of seed germs. These soil sterilization and seed treatment technologies along with screening chemicals for soil sterilization have been spread and become popular in Hebei, Shandong, Henan, and other provinces. They have also shown remarkable control on soilborne diseases and resulted in economic benefit, e.g., increasing farmers' income for 90,000-150,000 Yuan per 667 ha. The promotion of this technology can solve the problem of yam soilborne diseases and insect pests, with the advantage of reliable and stable effects. Furthermore, no pesticide residues and groundwater pollution ensure the quality and safety of agricultural products, very significant for the green sustainable development of yam industry.