桉小卷娥发生规律与防治的研究

A Study on Law of Regularity and Control of Pelochrista sp.

桉小卷蛾在我国桉树分布地区普遍发生,危害顶梢和嫩叶,严重影响幼林的高生长。1985～1987年、1991～1993年,先后在海南岛国营上埇林场、广东省雷州林业局对该虫进行了发生规律调查和防治试验,现将结果整理如下。1 生物学特性桉小卷蛾(Pelochrista sp.)在广东每年发生8～9代,且世代重叠,无越冬现象。成虫晚间交尾产卵,卵散产于嫩梢、嫩叶或嫩叶柄上,孵化后啜嫩梢或嫩叶结成苞。1～2龄幼虫藏于苞中取食,3龄后常爬出苞外取食或弃老苞另结新苞造成转移危害。幼虫大多5龄。

Meteorological regime is thought to be a key factor that has an important in- fluence on the occurring density of the population of Pelochrista sp. , an insect damages the eucalyptus. The occurrence culmination of the insect comes up around May, which causes heavy losses to juvenile eucalyptus plantation planted in the concurrent year. Strategies de- veloped for minmizing the losses include manipulation of the planting date after May for the least insect occurrence purposes and application of insect-resistant species of eucalyptus as well as spraying of 25% Dimilin Ⅲ in dilution of 1 500~3 000 times and rhizosphere applica- tion of 3% granular carbofuran 3~5 grams per stock.