The cell-free filtrate of X. nematophila TB culture exhibited a wide
range of inhibitory effect on plant pathogenic fungi and oomycetes in
vitro. Previous studies have reported the variation in antimicrobial
activities of different Xenorhabdus spp. strains to fungal pathogens9,18,24,27,35–
39. B. cinerea and P. capsici are the frequently reported
pathogens associated with tomato grey mold and pepper leaf scorch,
respectively, which result in marked agricultural economic losses
annually in China40,41. This study found that the cell-free filtrate of
X. nematophila TB culture showed strong inhibitory effect on the compounds produced by X. nematophlia TB may affect the cellular
process required for the germination of B. cinerea spores by multisite
inhibitors or interfere with respiration, and thus B. cinerea cannot
grow and reproduce normally to penetrate plant host. It has been
found that B. cinerea mycelia treated with the active compounds
from X. nematophlia YL001 culture showed morphological and
structural alterations such as swollen beads, septa malformation, cell
wall dissolution and cell liquid seepage47.