AUTHOR=Liu Rui , Chen Mengfei , Liu Boliang , Huang Kaiwei , Mao Zhenchuan , Li Huixia , Zhao Jianlong 

TITLE=A root-knot nematode effector manipulates the rhizosphere microbiome for establishing parasitism relationship with hosts

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1217863

DOI=10.3389/fmicb.2023.1217863

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p>Root-knot nematode (RKN; <italic>Meloidogyne</italic> spp.) is one of the most infamous soilborne plant diseases, causing severe crop losses every year. Effector proteins secreted by RKNs play crucial roles during plant-nematode interaction. However, less is known about whether RKN effector proteins can impact the rhizosphere microbial environment.</p></sec><sec><title>Methods</title><p>In this study, we investigated the rhizosphere microbiome community of <italic>MiMIF-2</italic> (a plant immunity-modulating effector) transgenic <italic>Arabidopsis thaliana</italic> with or without nematode infection using the Illumina high-throughput sequencing analysis.</p></sec><sec><title>Results and discussion</title><p>The results showed that the bacterial species richness index increased, while the fungi species richness index decreased in <italic>M. incognita</italic>-infected <italic>MiMIF-2</italic> transgenic <italic>A. thaliana</italic> plants. The relative abundance of genera such as <italic>Clitopilus, Komagataeibacter, Lactobacillus, Prevotella, Moritella, Vibrio, Escherichia-Shigella</italic>, and <italic>Pseudomonas</italic> was reduced in <italic>MiMIF-2</italic> transgenic <italic>A. thaliana</italic> plants compared to wild type, but was significantly increased after inoculation with <italic>M. incognita</italic>. The Cluster of Orthologous Genes (COG) function classification analysis revealed a decrease in the relative abundance of defense mechanisms, secondary metabolite biosynthesis, transport, and nematode infection catabolism-related functions in <italic>MiMIF-2</italic> lines compared to the wild type. These differences may be the reason for the increased susceptibility of <italic>MiMIF-2</italic> transgenic <italic>A. thaliana</italic> to nematode infection. Our results provide a new insight into RKN effector proteins and their association with the microbial community, host, and plant pathogens, which will lead to the exploration of new innovative ideas for future biological control of RKNs.</p></sec>