茼蒿霜霉病是我国许多地区茼蒿生产上的重要病害,近年来,随茼蒿种植面积的扩大,病害发生逐年加重。该病发病迅速,严重危害叶片,影响植株生长及产品质量,降低商品价值,影响经济收入。一、为害症状茼蒿霜霉病主要为害叶片。病害发生初期,先在植株下部老叶上产生淡黄色近圆形或多 Artemisia Downy mildew is an important disease in the production of Artemisia selengensis in many areas of our country. In recent years, with the expansion of planting area of ​​Artemisia selengensis, the occurrence of diseases is increasing year by year. The rapid onset of the disease, a serious threat to the leaves, affecting plant growth and product quality, reduce the value of goods, affecting economic income. First, the symptoms of chrysanthemum Downy mildew is the main damage leaves. Early disease occurs, first in the lower part of the plant to produce pale yellow near the old leaves or more