Fig. 4: The ability of native bacterial strains to suppress Meloidogyne incognita.

a Schematic representation of the design for evaluating the M. incognita-suppressing ability of native bacterial strains. Bacterial strains were isolated from the rhizosphere and root endosphere of M. incognita-infected cucumber. b Taxonomic classification of the M. incognita-induced strains. A total of 212 bacterial strains were randomly isolated, repeatedly purified, and phylogenetically identified based on full-length 16 S rRNA gene sequencing. c In vitro detection of the second-stage juvenile (J2) mortality of M. incognita (expresse as corrected M. incognita J2 mortality) caused by antagonistic strains. Fourty-five of these 212 bacterial strains were verified to cause a certain level of mortality in M. incognita J2s. d Proportion of functional strains taxonomically assigned to bacterial genera to the total functional strains. The red bars show strong suppression of M. incognita J2. e Ratios of plant performance of functional strain inoculation to the control (not inoculated). f, g In vivo verification of M. incognita infection. Gall (f) and egg mass (g) numbers per gram of plant roots are shown (mean ± SEM). The statistical significance of p values was calculated via a two-tailed, unpaired Student’s t-test. A pot experiment was conducted to verify the M. incognita-antagonistic functions of fourteen high-performance functional strains (HFSs; corrected nematode mortality > 90%, and ratio of plant performance compared to control > 1.0) in cucumber roots under M. incognita infection. N  =  9 biologically independent samples. Source data are provided as a Source Data file.