糯玉米田玉米螟卵赤眼蜂调查及利用技术研究

2008-2009年,在山西忻州市糯玉米田进行了玉米螟卵赤眼蜂消长动态、玉米螟卵优势种寄生蜂以及释放玉米螟赤眼蜂防治玉米螟等调查和试验研究。结果表明,一代玉米螟卵期没有采集到赤眼蜂寄生的玉米螟卵块,二代玉米螟卵初期始见赤眼蜂寄生的玉米螟卵块,田间赤眼蜂寄生率的时间变化具有典型的害虫-天敌跟随现象,后期田间赤眼蜂自然寄生率很高;玉米螟赤眼蜂为当地糯玉米田玉米螟卵中的优势种寄生蜂;释放玉米螟赤眼蜂可有效控制糯玉米田二代玉米螟的危害,玉米螟卵块校正寄生率达79.73%~96.71%,雌穗被害率被控制在5%以下。

Study on Research and Techniques in Use of Trichogramma ostriniae to Asian Corn Borer,Ostrinia furnacalis in the Field of Waxy Corn

Efforts were conducted to investigate the population dynamic of Trichogramma spp.,the dominant parasitoid of Asian corn borer,Ostrinia furnacalis,and to experiment on the releasing of Trichogramma ostriniae to O.furnacalis as a method to control O.furnacalis in the waxy corn field in Xinzhou city during 2008 to 2009.It showed that no parasitized egg masses by T.ostriniae were found during the egg stage of the first generation of O.furnacalis,until the beginning of the egg stage of the second generation.The time dynamic of the T.ostriniae parasitism rate was typically adapted to the natural enemy following-up pattern,as seen in the much higher natural parasitism rate in later stage of the period.T.ostriniae was the dominant parasitoid of O.furnacalis in local waxy corn fields.The damage to waxy corn by the second generation of O.furnacalis was efficiently controlled by releasing T.ostriniae.The corrected parasitism rate of egg masses were 79.73%~96.71% and the percentage of damaged female ears were controlled to less than 5%.