棉花由露地栽培改为塑膜覆盖栽培后,棉花生育进程加快,多种病、虫、杂草的发生以及危害发生了新变化,防治策略和措施必须与新的情况相适应,以确保覆盖棉花的增产效益。 病害方面 (一)棉苗根病:是由红腐、立枯、炭疽等构成的复合性病害。覆盖田由于温、湿度高,棉苗生长快,受早春低温影响大,而病原菌多在土壤中通过寄主根部入侵,土温 Cotton from open cultivation to plastic film cultivation, the process of cotton growth accelerated, a variety of diseases, insects, weeds and the occurrence of a new change in the hazards, prevention and control strategies and measures must be consistent with the new situation to ensure coverage of cotton Yield increase. Diseases (A) Cotton seedling root disease: red rot, standing withered, anthrax and other complex diseases. Due to the high temperature and high humidity, the cotton seedlings grow fast and are affected by the low temperature in early spring. However, the pathogens mostly invade in the soil through the host roots. The soil temperature