Selection of High Efficient Beauveria bassiana Strains against Ostrinia furnacalis

White worms of Ostrinia furnacalis were collected from fields in Jilin Province the isolation and purification of new Beauveria bassiana strains were undertook.7 strains(D 1worm-5,D 1 worm-9,L 2 worm-8,L1-1-1,D6 worm-2,D10 worm-2,S9 worm-X-1) were obtained,which showed high sporulation,germination rate and virulence against larva of Ostrinia furnacalis.The results illustrated that the sporulation of all 7 strains were between 16-33.5 billions spores /g by solid fermentation,the germination rate of spores were 48%-93% at 16 hours and 100% at 22 hours post cultivation,respectively.The muscardine lethal rate was 93%-100% at a 10.6 billions /ml spores density.The virulence was not correlated to sporulation and germination rate,but positively correlated to spores density and acting time.