Bacillus licheniformis JF-22 to Control Meloidogyne incognita and Its Effect on Tomato Rhizosphere Microbial Community

Abstract

<i>Meloidogyne incognita</i> is one of the most destructive soil pests, causing serious economic losses in tomato production. Here, <i>in vitro</i> experiments demonstrated that the <i>Bacillus licheniformis</i> strain JF-22 has the potential to prevent <i>M. incognita</i> infection. A pot experiment confirmed that <i>B. licheniformis</i> strain JF-22 isolated from the tomato rhizosphere soil and planted in the tomato root-knot nematode disease area effectively prevented and controlled <i>M. incognita</i>, reducing its negative effect on tomato growth. Additionally, the composition of volatile substances secreted by <i>B. licheniformis</i> strain JF-22 was analyzed using solid-phase microextraction and gas chromatography-mass spectrometry. We detected acetoin, 2,3-Butanediol, [R-(R*,R*) ]-, and hexamethyl cyclotrisiloxane as the main components among these volatiles. Using MiSeq sequencing technology and bioinformatics, we analyzed the influence of <i>B. licheniformis</i> strain JF-22 on the microbial community of the tomato rhizosphere. <i>B. licheniformis</i> strain JF-22 changed the composition of the microbial community; particularly, it significantly reduced the diversity of the fungal community. Furthermore, using the FUNGuild and PICRUSt databases, we predicted the effect of JF-22 on microbial community function. In conclusion, <i>B. licheniformis</i> strain JF-22 may be considered as a potential biocontrol agent against <i>M. incognita</i>.