螨类以前是不被人们重视的,自从第二次世界大战后,由于农药大量的不合理使用和环境污染,导致生物益害之间平衡失调,特别是叶螨已成为世界性大害虫之一。水杉是我国独有的珍贵树种,被称为“活化石”,国家一级保护植物。目前,全世界五大洲70多个国家和地区从我国引种栽植,国内整片造林已达70多 Mites have not been valued by people before. Since the Second World War, due to the large amount of unreasonable use of pesticides and environmental pollution, the imbalance between biological benefits has been caused. In particular, spider mites have become one of the world’s largest pests . Metasequoia is a unique precious species of our country, known as “living fossils”, the national level to protect plants. At present, more than 70 countries and regions in five continents all over the world are introduced and planted from China, and the entire afforestation in China has reached more than 70