梨枝圆盾蚧的发生规律和防治技术研究

The Occurrence Regularity and Control Methods of San Jose Scale, Diaspidiotus perniciosis (Comstock)

梨枝圆盾蚧在陕西省苹果园1a发生3代。主要为害时期为越冬代4～5月,第1代6～7月,第2代8～9月。此虫主要为害苹果树枝条,而以为害果实造成的经济损失最大。防治上应重点抓好冬春修剪有虫枝条,保护利用天敌,以及果树开花前越冬代若虫期和6月上中旬第1代初龄若虫期的化学防治。

Diaspidiotus perniciosis (Comstock) occurs 3 generations per year in apple orchards of Shaanxi Province. Main damaging period of over-wintered, first and second generation nymphs appears in April ~ May,June ~ July and August ~ September respectively. Diaspidiotus perniciosis injured mainly the branches of apple tree, but economic injury is maximum when the insect pest feed on fruit. Cutting the ranches with nymphs is a key of controlling its occurrence in winter and spring. Other control measures include that protecting and using the natural enemy of the insect pest and spraying insecticides both before flowering stage of apple trees (nymph stage of over-wintered generation) and in early and middle June (first instar of nymph).