Abstract:

Objective: An antagonistic strain against Fusarium solani was selected from the rhizosphere soil of ginseng, and
its inhibitory effect on plant pathogens was researched preliminarily. Methods: The strain was separated from the rhizosphere
soil of ginseng by the plate dilution method, selected directly using the pathogenic fungus Fusarium solani as the indicator
strain, and identified based on morphological, physiological and biochemical characteristics and 16S rDNA phylogenetic
analysis. The effects of the cell-free fermentation filtrate on mycelial growth and spore germination of pathogenic fungi were
determined. Meanwhile, the antagonistic spectrum of the antagonistic strain was assessed. Results: Strain HB-3 was isolated
from the rhizosphere soil of ginseng and exhibited an excellent antagonistic effect on Fusarium solani. It was identified as
Bacillus amyloliquefaciens. Inhibition zone test and growth inhibition detection showed that strain HB-3 had the strongest
inhibitory effect on mycelium and spores of pathogenic fungi, and displayed a wide antagonistic spectrum, suggesting
obvious inhibition on fungal pathogens of ginseng such as Fusarium solani, Phytophthora cactorum, Cylindrocarpon
destructans, Sclerotinia schinseng and Botrytis cinerea. Conclusion: Strain HB-3 has a strong effect on biological control of
Fusarium solani showing a significant inhibitory effect on the growth of the pathogenic fungus.

Key words: Fusarium solani, Bacillus amyloliquefaciens, cell-free fermentation filtrate, antagonistic spectrum