| Acremonium hansfordii was isolated from natural infectioned larvae of the Myzus persicae of Yuzhong County, Gansu Province Huang Jiazhuang in the Pesticide Analysis Laboratory of Gansu Agricultural University and had a stronge strain of Brevicoryne brassicae by bioassay.Professor Li Zengzhi identified as the Acremonium hansfordii, Anhui Agricultural University.To this entomogenous fungi used in agricultural production as soon as possible, the paper studied on Ahy1 WP and Emulsifiable Conidia Suspensions preparation of Ahy1.Results are as follows:1.Through preliminary research on the production technique of the Acremonium hansfordii Ahy1 strains, wheat bran medium was selected to be the first solid culture medium and the sixth day was the best cultured time.The second liquid culture was the potato-sugar cultivation medium, by oscillating cultivated three days(25±1℃,120r/min); Screening low-quality rice substrate was third sporulation cultivation medium and collectting spore powder preliminary by the detection of Acremonium hansfordii Ahy1 strains pureness and viability from 13 types culture medium.The powdery product was in high quality with pureness of 5.8×1010 conidia/g, water content of 6%, and viability of 93.5%,it provided the basis for further formulations processing.2.We studied the influence of some wettable power adjuvants on the conidia of Ahy1.Results indicated that 4 carriers(Talc,Bentonite,Diatomite,Calcium carbonate),Sodium lignosulfonate as a dispersion agent ,SDBS as a wetting agent,CMC-Na as a stabilizer,humic acid and fluorescein sodium injection as UV protectants showed favorable biological compatibility to the conidia of Ahy1 and suited for the preparation of Ahy1 WP.10%Ahy1 WP was in high quality with pureness of 5.8×108 conidia/g,water content of 1.729%,suspension rate of 82.24%,wetting time of 136.01s and fineness of 93.62%.10% Ahy1 WP stored in different temperature ,the results showed that the low temperature has little effect on formulation, but the high temperature has great influence on the stability of formulation .3.Added pure conidia powder in different types of solvent oil to each solvent of A-F. Through regular spore activity rate detection ,it found that solvent oil D, E, F spores on the high activity, can be used as solvent for the Emulsifiable Conidia Suspensions.Containing 0.1-1% of three kinds of emulsification G,H,I and then presenved at ambient temperature. The viability of the conidia combination of solvent and emulsifier during the was examined using samples from each storage.A combination of solvent E and 0.3% I was found most compatible to Acremonium hansfordii Ahy1 and could be used as primary components of emulsifiable conidia suspensions for formulation.The other components selected reviously included the use of 0.3% CMC-Na (sodium carboxymethyl cellulose) as a suspension stabilizer,0.1% humic acid as a desirable UV-protectant.Emulsifiable Conidia Suspensions preparation of Ahy1 is 8.5×108conidia/mL,and could spread well in the water.4. Bioassay of the formulations of Ahy1 WP and Emulsifiable Conidia Suspensions preparation of Ahy1 on the Brevicoryne brassicae, showed that the two formulations on the Brevicoryne brassicae adjusted mortality in 24h at the low level, and after 72h showed obviously killed in insects , especially Emulsifiable Conidia Suspensions preparation of Ahy1.The adjusted mortality were 82%,77.7%,60.08% and 46.03%; Abamectine had a high adjusted mortality to Brevicoryne brassicae in 24 h, 97.6%,81.91%,73.27% and 65.93%,respectively.we found that Ahy1 was more suitable for Emulsifiable Conidia Suspensions preparation in the research and generalization.
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