Inhibitory Effects of Two Biocontrol Fungous Strains on Poplar Canker Botryosphaeria dothdea Biomass Change of Middle Aged Forest of Qinghai Spruce along an Altitudinal Gradient on the North Slope of Qilian Mountains Isolation, identification and biological characters of Trichoderma asperellum T31 Influences of the biocontrol strain ANTI-8098A, Bacillus cereus on the growth competition between the virulent and avirulent strains of Ralstonia solanacearum Identification on an antagonistic rhizobacterium X3 from rhizosphere of cucumber A Study of Bacillus thuringiensis Strain LTS290 Inhibiting Fusarium