Abstract:

In order to obtain the original antagonistic bacteria strains of high efficiency and broad spectrum for preventing and controlling Camellia oleifera diseases, and to explore the effects of biological control, 223 strains of bacteria were isolated from soil samples. Antagonistic bacteria were selected by using confrontation culture method and activity determination of fermentation products. The results showed that: using Colletotrichum gloeosporioides and Fusarium proliferatum as indicators, 21 strains were selected by plate confrontation method with inhibition zone width were 5.0-12.5 mm. They were 9.9% in accounted for the separation to the total number of bacteria, of which the strain Z26 showed the best inhibition activity; Re-selection tests by using confrontation culture method showed that the fermentation product of 21 strains had stronger antagonistic activities to 6 plant pathogens, of which 8 strains showed inhibition activity strong antagonistic activities to C. gloeosporioides and 4 strains showed inhibition activity strong antagonistic activities to F. proliferatum with inhibition zone width were ≥10.0 mm. They were 38.1% and 19.0% respectively in accounted for tested strains, of which the strain Z26 showed the best inhibition activity. The determination tests of fermentation product indicated that the antibacterial activity of 7 strains of fermentation broth could inhibit completely to the growth of C. gloeosporioides and the effect was obvious, fermentation filtrate inhibitory rate was 33.3%-58.3% and the effect was not obvious; bacteriostasis rate of more than 50.0% of the only Z17, Z26 2 strains. Therefore, the strains Z17 and Z26 had better antibacterial effect and biocontrol potential to C. oleifera diseases; they could be used as antagonistic strains of alternative of C. oleifera diseases.