Study On Application Characteristics And Formulation Of Isaria Fumosorosea IF-1106

Green safety and efficient prevention and control of greenhouse pests have become a major problem that plagues the development of the greenhouse industry.“Using fungal to control insects" is safe and efficient,which is one of the important research directions of modern ecological plant protection.Isaria fumosorosea is a globally distributed pest biocontrol fungus that is widely used in the control of greenhouse pests abroad.Registered fungal insecticide products can effectively control whitefly,aphids,and thrips.In this study,a highly pathogenic potential biocontrol strain was used as the research object,and the research on the application characteristics of the conidia and large-scale fermentation technology and the development of wettable powders.The aim is to develop high-efficiency,broad-spectrum,and stable Isaria fumosorosea IF-1106 products with independent intellectual property rights,so as to realize the efficient application and promotion of " using fungal to control insects " biocontrol technology.The main results of this study are as follows:1.Formulation characteristics of Isaria fumosoroseaPoly2D fitting model shows that different nutritional conditions have a great influence on the heat resistance of spore.Taking the spore heat resistance evaluation index at 45℃ for 5h,it is clear that the heat resistance of spores produced by rice and corn as solid fermentation substrates is significantly higher than other substrates,and the addition of 1% vegetable oil can further improve the resistance of conidia.Supplementing 5g/L carbon source in rice flour or corn flour can further improve the heat resistance of spores.Both UV-A and UV-B will affect the germination of Isaria fumosorosea,and the sensitivity of the strain to UV-B is significantly higher than UV-A.The UV sensitivity of the strain reflected by the plate colony counting method is higher than that of the hanging drop method.The semi-germination radiation dose obtained by fitting with a single exponential decay model can reflect the UV-B resistance of the strain.The semi-germination radiation dose of the spores of the strain reflected by the hanging drop method is between 1.5?2 J/cm2,and the spore semi-germination irradiation dose reflected by the method was between 0.5?0.7J/cm2.Conidia can effectively adsorb the main types of surfactants in dilute surfactant solutions(≤2g/L),and their saturated adsorption capacity is between 10?40mg/g.The adsorption of low molecular weight anionic and nonionic surfactants is an "L" type isotherm,and the adsorption of polymers and silicone surfactants is an "S" type isotherm.2.Study on the large-scale fermentation technology of Isaria fumosorosea Brown rice is an ideal solid fermentation substrate for Isaria fumosorosea,and the addition of0.005% vitamin C and arginine can effectively promote the growth and spore production of the strain.Using 50g/L rice flour+5g/L maltose as the liquid medium,the inoculation amount is 5%,and cultured at 30℃ and 240r/min for 3 days to obtain a spore production of 1.78×108blastospores/m L.The above-mentioned solid-liquid fermentation constitutes a diphasic fermentation process,and the spore yield can reach(1.52±0.82)×109 conidia/g.After the conidia are air-dried at 28℃,the survival after 36 weeks of low-temperature storage at 4℃ is more than 85%.3.Development of wettable powder of Isaria fumosoroseaThe SC90 value obtained by the four-parameter Log-logistic model for compatibility fitting can be used for biocompatibility evaluation of adj UV-Ants and strains.The strains had high compatibility with the additives CMN,CMS Na and T 80,and the compatibility concentration threshold was given.A scheme for optimizing dispersing suspension adj UV-Ants by light transmittance method was established.The screened organic pigment Py-12 and Py-14 UV protection adj UV-Ants has good compatibility with the strain,and the germination rate of the spore-containing suspension containing the adj UV-Ant can be increased by more than 70% after UV-B irradiation.4.Determination of the properties and control effects of Isaria fumosorosea formulationSelf-made WP of Isaria fumosorosea IF-1106,and the main technical indicators of the formulation reached or exceeded the relevant technical standards of similar products.The field efficacy test of the formulation showed that the control effect began to appear after 3 days,and the average control effect at 7 days was higher than that of the chemical control.The control effect in the carbon-rich greenhouse was higher than that in the ordinary greenhouse.At 14 days,the average prevention effect reached 80.8%.In conclusion,This study aimed at the potential biocontrol strain Isaria fumosorosea IF-1106,clarified its application characteristics,explored the scale fermentation technology,developed a WP formulation,and evaluated its performance.It lays a certain technical foundation for the realization of “using fungal to control insects” based on Isaria fumosorosea.