1983年以前,在记载小麦成株白粉病病情的方法上,各地标准不一,不便交流比较。全国小麦白粉病1983年会议商定,采用墨西哥“玉米、小麦改良中心”禾谷类作物叶部病害分级标准记载。经两年试用,我们认为其原则可取,但它是按小麦成株约7片叶的病情,分成0—9级(以下简称“九级法”, Before 1983, in the method of recording the disease of wheat powdery mildew, different standards, inconvenient to exchange and comparison. National wheat powdery mildew Conference in 1983 agreed to adopt Mexico’s “corn, wheat improvement center” classification of cereal crop disease grading standards. After two years of probation, we think its principle is desirable, but it is divided into 0-9 grades according to the condition of about 7 leaves of wheat plant, (hereinafter referred to as the “nine-level method”