Study On Parasitic Fungi-Verticillium From Cereal Cyst Nematode(Heterodera Avenae)

Verticillium spp. were isolated from soil, females and eggs of cereal cyst nematode with a selective medium from Fanshan, Daxing, Pinggu, Tongzhou of Beijing, Dingzhou, Shijiazhuang of Hebei, Jiaozhou of Shandong, Tianmen of Hubei, Guizhou and Laiyuan of Qinghai. Those results showed that Verticillium spp. are commonly occurring in soil and nematode eggs in North China. The percentage of infected eggs and females of cereal cyst nematode is high in soil with a high content of Verticillium spp..With wheat ripping, the percentage of infected eggs of cereal cyst nematode will increase. Colonies isolated from soils, females and eggs of Cereal cyst nematode had been identified as Verticillium suchlasporium var. suchlasporium.Gams & Dackman.The studies on the biological characters of Verticillium spp. under different temperatures in dark and light conditions showed that it is easy to cultivate Verticillium spp. on the MA medium in the lab. The optimum cultivation condition for Verticillium spp. is on the MA medium at 25℃ in the darkness.Testing cassettes were used in this research to measure the number of eggs of cereal cyst nematode infected by conidiospore of Verticillium spp., the results showed the percentage of infected eggs was higher and the eggs were infected at a higher race.Infected soil by soybean cyst nematode was treated with origin liquid and 50 times dilutition liquid of application fungi, the results showed that the isolate could improve soybean root growth, increase fresh weight of root, decrease cyst numbers per gram of fresh root significantly. The decreased ratio of cyst per fresh gram root treated with strain HubeilV, GuizhouIA, LaiyuanI, GuizhouII and Shuangfutou were 71.34% 71.27%, 69.1%, 66.09% and 59.68% respectively.