| This paper is to research the contol of Anomala schoenfeldti with Metarhizium anisopliae. It includes the isolation and selection of Metarhizium anisopliae; its host specificity and compatibility to chemical pesticide, its synergism when used together with chemical pesticide as well as its synergism mechanism. The following are the investigation results: (1) By isolating directly from infected insects and selected medium , from the Anomala schoenfeldti and field isolate the Metarhizium anisopliae , the Beauveria bassiana; the B. brogniartii and Paecilomyces fumosoloseus four kinds 120 strains , among which 33 from Anomala schoenfeldti larvae 22 from B. brogniarlii, 1 from Beauveria bassiana; the isolated Metarhizium anisopliae are all M.anisopliae var. anisopliae and the non-isolated are M.anisopliae var. majus,(2) By 3 tiers selection , select a strain ASMa-9802 of Metarhizium anisopliae that is highly pathogenic, high temperature endurance , and sporulates well on the target host, its LC50 to three year larvae of Anomala schoenfeldti is 2.2 X105 conidia/ml; and under the treatment of 5.0 X 107 conidia/ml and 1.0 X 107 conidia/ml, LT50 is 7.3 ?1 .Od and 8.5 + 1 .Od.(3) Strain ASMa-9802 of Metarhizium anisopliae bears high host specificity. The research found that this host specificity is mainly caused by the attachment of conidum to the host cuticle and the germination difference.(4) In the medium ASMa-9802 strain of Metarhizium anisopliae has strong endurance to most of the organophosphate insecticide and all of the carbamates insecticide and pyrethroid insecticide and it has less strong endurance to IGR. However the soil experiment shows that the insecticide, which may strongly effect the germination of ASMa-9802 strain of Metarhizium anisopliae conidum in the medium, hardly has any influence to ASMa-9802 strain of Metarhizium anisopliae in the soil.In the medium it has been tested that most of the 16 insecticides effect greatly the germination of the ASMa-9802 strain of Metarhizium anisopliae or the growth of mycelium, of which the greatest are organosulfur and benzimidazoles fungicides.With normal use thickness , lenacil , glyphosate ; pendimethalin fluroxypyr and 2,4-D do not have any effect to the growth of mycelium of the ASMa-9802 strain of Metarhizium anisopliae, and the rest four herbicides , such as chloridazon, metolachlor , desmedipham and phenmedipham, have great influence to it.Under the UV irradiation (wavelength 256nm , dose 825 u W/cm 2), the ASMa-9802 strain of Metarhizium anisopliae in the low concentration area 2,0 X 107, 5.0 X 106conidia/ml, its virulence decreases as the irradiation time increases , nearly has decreased to 60% in 24 hours. But in high concentration area 6.OX 108conidia/ml , its virulence doesn't vary as the irradiation time increases , it keeps 100% all the time.(5) Inside experiment shows that when ASMa-9802 is used together with other insecticide, all the medicament and its concentration increased its insect killing effect, especially when mixed with fenthion and fenitrothion (2.0 u g) , the synergism is quite remarkable and the former is much more superior than the latter in its synergism range and speed. When ASMa-9802 is used together with IGR, teflubenzuron and flufenoxuron can produce obvious synergism. Synergism is not clear when ASMa-9802 is used together with chlorfluazuron ,and there is no synergism when ASMa-9802 is used together with tebufenozido.Within 5d , in the ASMa-9802Xfenitrothion mixture treatment area, the larvae feeding quantity (0.96?.75g) decreased distinctively compared with the contrast area, decreased about 45%. But due to the limitation of experiment time, the larvae feeding quantity in single area and mixture area doesn't show any difference.In the potted lawn control experiment made in the field , when ASMa-9802 was used with fenthion (100 U g) and flufenoxuron (50 u g) , its prevention effect to one year larvae was obviously higher than separate treatment area. And the prevention effect was...
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