螟虫长距茧蜂的预测方法和保护利用

FORECAST METHOD OF OCCURRENCE OF MACROCENTRUS LINEARIS(NEES) AND ITS PROTECTION AND UTILIZATION

螟虫长距茧蜂是玉米螟幼虫的主要寄生性天敌,虫态历期随温度升高及寄主龄期增高而缩短。玉米螟幼虫被寄生率的大小与玉米螟虫口密度、该天敌的数量、湿度和降雨量有关,相关式为:Z=1.2284+2.6521x_4+0.8913x_5-4.6525x_6±1.2205。第二代玉米螟为害玉米的动态模型为:R_1=5.3177ENY·(1-Z)]^(0.3857)、为害棉花的动态模型为:R_2=3.365[NY·(1-Z)]^(0.443),第三代玉米螟为害棉花的动态模型为:R_3=0.1980[NY_1·(1-Z)]^(0.4090)。因此,保护利用该蜂,可以控制玉米螟对玉米和棉花的为害。

Macrocentrus linearis(Nees)is an important parasitic natural enemy of Asiatic Corn Borer(ACB)(Ostrinia furnacalis). The durations of different instar forms of M. linearisshorten with rise of temperature and advance of hostinstar. Rate of parasitize'd larvae of ACB is correlated with population density of ACB, number of parasitic wasps released, relative humidity and rainfall; the correlation equation is Z=1, 2284+2.6521x_4+0.8913x_5-4.6525x_6. The two dynamic models of ACB infestation on maize and cotton in second generation are R_1=5.3177[NY.(1-Z)^(0.3875) and R_2=3.365[NY.(1-Z)]^(0.443). The dynamic model of ACB infestation on cotton in third generation is R_3=0.4980[NY_1(1-Z)]^(0.409). According to these dynamic models, the prediction of occurrence quantity and date of ACB as well as M. linearis may help to decide practice of chemical control of ACB and fix date of insectide application.