A Screening Study Dominant Trichogramma Its Biocontrol Efficiency Against Parasitic Corn Borer Heilongjiang

Corn borer commonly known as the maize borer, belongs to the Lepidoptera and Pyralidae. Is themost important pest insect of maize in Heilongjiang province. Especially in recent years, Asian cornborer happen frequently, it caused maize production and reduce the farmers’ income. The method ofprevention and control the corn borer is limited, is included the chemical method and method ofagriculture and the limitations of other methods. It leads to corn borer for corn harm is more serious. Soa more effective method of prevention and cure is very need. In this thesis, the advantages ofHeilongjiang screened Trichogramma parasitic corn borer, corn borer collected by Trichogrammaparasitized egg masses from the field. Isolation and identification of type, select a higher rate ofparasitic wasp species in the laboratory, field survival time of adult Trichogramma, field efficiencyexperimental comparison, combined with the actual situation of Trichogramma factory production,considering from the control effect, production costs and efficiency, etc., to determine the advantagesof a parasitic wasp species Heilongjiang corn borer, corn borer prevention of Heilongjiang Provinceprovides a feasible way to solve the difficult problem of borer prevention, agricultural production andrural incomes contributed.Trichogramma is collected from Harbin, Qiqihar, Jiamusi, Mudanjiang, Qitaihe, Shuangyashan,Hegang in Heilongjiang province. The corn borer egg masses, natural parasitism was7.2%,4.7%,12.5%,7.6%,10.0%,3.6%,8.2%, is identified there T.dendrolimi wide Trichogramma, DarkTrichogramma, rice borer Trichogramma, and Trichogramma Trichogramma, indicating the nature,capable of parasitic corn borer there are many types of Trichogramma egg, but the low rate of parasitism,can not determine what kind of parasitism rate.Research the parasitic rate of different kinds Trichogramma in the corn borer eggs. The block cornborer eggs parasitic rate of Trichogramma dendrolimi Matsumura, Trichogramma confusum Viggiani,Trichogramma ostriniae Pang et Chen, Trichogramma evanescens Westwood, Trichogramma euproclidis(Girault), Trichogramma japonicun Ashmead is72.4%,46.0%,82.1%,8.60%,1.20%,6.90%;theparasitic rate of granular corn borer eggs is55.7%,39.5,59.3%,6.8%,2.0%,5.1%. According to thehigher rate of parasitic selected three kinds of Trichogramma, respectively is Trichogramma dendrolimiMatsumura, Trichogramma confusum Viggiani and Trichogramma ostriniae Pang et Chen.Under natural conditions, the survival time of three Trichogramma adult, the average survival timefor the first day Trichogramma dendrolimi Matsumura80.6,93.8the next day, the third day64.6,22.2fourth day, fifth day0.6, the average number of surviving Trichogramma ostriniae Pang et Chen for thefirst day of83.8,94.6the next day, the third day21.4,6.6fourth day, fifth day of0.2, with an averagesurvival of Trichogramma confusum Viggiani The first few days of83.4,93.2second day, third day32.6,10.8fourth day, fifth day1.0. Comparison, in three species of Trichogramma wasps emerged outafter two days of pre-adult survival high number, the third day, the number of surviving drops, thenumber of which survived and Trichogramma Trichogramma decline obvious.Different types of Trichogramma against corn effect Trichogramma dendrolimi Matsumura, Trichogramma ostriniae Pang et Chen, Trichogramma confusum Viggiani average Trichogrammacontrol effect is68.47%,83.80%,49.67%, with an average yield loss is to restore7.27%,9.49%,4.64%.Comprehensive analysis, the advantages of Heilongjiang Province screened parasitic corn borereggs and Trichogramma Trichogramma is T.dendrolimi. From the average number of surviving seeabove ostriniae T.dendrolimi, from an economic point of view, the province’s industrial productionT.dendrolimi shape, use tussah breeding eggs, low production costs (2yuan/acre), high efficiency fanbees, and the use of rice breeding Trichogramma moth eggs, high production costs (2.5yuan/mu),numerous bees efficiency, low spurious, industrial development is lagging behind..In the actual production, according to the results of this study suggest choose the Trichogrammadendrolimi Matsumura which has high efficiency.