(一)蚧虫的为害 1.有害蚧虫类的传播蚧虫类是以固着在植物上或几乎不活动的状态下生活着,而不像同类中同翅目害虫的浮尘子和蚜虫那样活跃的飞翔或按季节性远距离迁移。蚧虫在初龄幼虫(若虫期)会爬行移动或随风迁移,但是这种情况也绝不可能以群聚方式迁移到几公里远。某种蚧虫能从其发源地迁移到邻近距离的村庄、县、国家以及大陆之间,使其遭到为害的例子, (A) Insects of scale insects 1. Spread of harmful scale insects Scale insects are immobilized on plants or barely active, not as active as dust bugs and aphids in the homopteran pests Fly or seasonal seasonal migration. Scale insects can crawl or migrate in the first instar larvae (nymphs), but it can never be the case that they migrate in clusters as far as a few kilometers. An example of a species of scale insectivore that can migrate from its place of origin to villages, counties, countries and continents in close proximity to it,