陕西省菜粉蝶寄生昆虫调查及其利用

对陕西14个县、市菜粉蝶寄生昆虫调查结果,得到原寄生性天敌:广赤眼蜂Trichogramma evanescens、松毛虫赤眼蜂T.dendrolim、螟黄赤眼蜂T.chilonis、亚洲玉米螟赤眼蜂T.ostriniae、菜粉蝶绒茧蜂Apanteles glomeratus、绒茧蜂Apanteles sp.、蝶蛹金小蜂Pteromalus puparum、粉蝶粗腿小蜂Brachymeria femorata和追寄蝇Exorista sp.等9种。其中广赤眼蜂是卵寄生蜂中的优势种类。全省平均寄生率11.73%～15.74%,6～8月是寄生的高峰期,寄生率为32.46%～46.42%。一年中不同时期、不同地区寄生率差异显著。幼虫期和蛹期寄生率很低。

A SURVEY ON THE PARASITES OF THE CABBAGE WHITE BUTTERFLY, PIERIS RAPAE L. AND THEIR UTILIZATION POTENTIALTITY IN SHAANXI

This paper deals with the results of a survey of the parasites of the cabbage white butterfly. Pferis rapae L. in 14 counties, cities of Shaanxi. In total, 9 species of primary parasites have been found. They are: Trichogramma evanescens,T. dendroliani, T. clalarsis, T. ostriniae, Apanteles giorneratus, Ayanleles sp.,Pterrnnalas puparum. Brachymeria femorata and Exarista sp. Trichogranrmcr evanescens is dominant species of the parasites. Its average parasitization percentage of eggs has been found to range from 11.73% to 15.74%.Higher parasitization percentage of eggs has been found to range irom 32.46% to 46.42% in June to August. The results of the survey have suggested that the parasitization percetage of eggs show signifisent difference in different periods a year and regions. The parasitism percentage of larvae and pupae has been found to be lower. In accordance with the results of the survey, the authors analysed the reasons of the parasitical lower percetages of eggs,larvae and pupae, discussed the potentialities and methods of the protection and utilization of the Triclmgrmrana evanescens as the chief natural enemies of the pest.