小叶女贞新害虫黄环绢须野螟生物学特性

黄环绢须野螟Palpitaannulata(Fabricius)是小叶女贞(LigustrumquihouiCarr.)上新出现的一种害虫,严重危害小叶女贞叶片,造成植株枯萎、死亡,同时也危害金叶女贞(L.vicaryi)。该虫在湖南省衡阳地区1年发生3代,以蛹在土中越冬。越冬代成虫和第1、2代成虫分别于4月下旬、5月下旬和6月下旬出现。成虫产卵于嫩梢顶端叶片上,卵期3d,幼虫期9～12d。5月上旬和6月上旬分别是第1代和第2代幼虫盛发期,危害最重。越冬代成虫羽化期喷药是防治该虫的关键,在成虫期和幼虫期分别用40%氧化乐果乳油、50%辛硫磷乳油1000～1200倍或25%溴氰菊酯乳油2500～3000倍稀释液喷洒寄主叶面,可控制该虫危害。

Bionomics of a new pest, Palpita annulata on Ligustrum quihoui

Palpita annulata (Fabricius) is a newly-appearing pest insect, which damages the leaves of Ligustrum quihoui Carr. seriously, causes plants withered and dead ,and damages L. vicaryi also. It has three generations a year and over-winters as pupa in the soil in Hengyang area, Hunan Province. The adults of the over-wintering, first and second generations emerge in the last ten days of April, May and June respectively, and lay eggs in the top leaves of slender branches. Egg stage lasts three days,larval stage 9～10 days. The occurring peak of the first and second larva appears in the early May and the early June respectively, with most serious injury. The period of the over-wintering adult emerges is key time to control, and spraying the surface of leaves with 1:1 000～1 200 solution of 40%Omethoat EC, 50%Phoxin EC, or 1:2 500～3 000 solution of 2.5% Decis EC in the adult stage and larva stage is very effective for control of this pest.