Study On Isolation, Identification And Characteristic On Entomopathogenic Fungi

Two entomopathogenic fungi named Bb-d and NL0710 were isolated from disease-infected dead insects. Bioassay results showed that two isolates had biological activities on Plutella xylostella, Spodoptera exigua, Lipaphis erysimi, and Lasioderma serricone. Through morphological and molecular identification, Bb-d is Beauveria bassiana, Beauveria, Moniliaceae, Monilales, Hyphomycetes, Deuteromycotina and NL0710 is Paecilomyces farinosus, Paecilomyces, Moniliaceae, Monilales, Hyphomycetes, DeuteromycotinaThe influence of 9 kinds of chemical pesticide on the growth of mycelium and germination of spores of Bb-d and NL0710 indicated that all the tested pesticide inhibited the growth of mycelium and germination of spores of two isolates. Inhibition ability is higher as the pesticide concentration increases. Bb-d could be mixed with MCPA, deltamethrin, malathion and NL0710 could be mixed with chlorfluazuron, MCPA, malathion, deltamethrin under fixed concentration of the pesticide.7 kinds of carbon sources, 6 kinds of nitrogen sources and 12 different C:N ratio were studied using SDAY medium. The results indicated that sugar can influence on the growth of mycelium and volume of spores of two isolates in which glucose is the best carbon source for growth of mycelium. In nitrogen sources, the peptone is the best sources for Bb-d, and beef extract was the best sources for N10710. The growth of mycelium and volume of spores is the best while C:N ratio is 32:8. The growth of mycelium and volume of spores were decided by quantity not that proportion of C and N.