杨圆蚧属同翅目盾蚧科害虫,主要分布在“三北”地区,为害箭杆杨、小叶杨、钻天杨、银白杨、青杨、旱柳等。成若虫在幼嫩枝干上刺吸树液,因蚧壳密布,造成树叶发黄变小,枝干部常形成瘤状突起,严重时树皮开裂,极易感染烂皮病,后期常引起枯枝或全枝枯死。 一年发生一代,以若虫越冬。4月上旬,雄若虫开始化蛹,4月下旬至5月中旬为化蛹盛期。5月中旬雄成虫开始羽化,5月下旬至8月中旬为羽化盛期。4月下旬雌若虫变为雌成虫,5月下旬至7月上旬为雌成虫 Yang Yuan Kui is a Homoptera Hymenoptera pests, mainly distributed in the “Three Norths” area, the harm arrowhead poplar, Populus trichosanthes, Poplar, silver poplar, green poplar, Salix and so on. Into the nymph on the young branches thorns sucking tree liquid, due to mellement shell, resulting in yellowing smaller leaves, branches often form tumor-like protrusions, severe bark cracking, easily infected with rot disease, often lead to late dry Branch or whole branch dead. One generation a year to nymphs wintering. In early April, male nymphal began to pupate, from late April to mid-May for the pupation peak. In mid-May adult male began to emerge, from late May to mid-August for the feather peak. Female nymphs become female adults in late April, female adults from late May to early July