Deciphering bacteria associated with a pre-parasitic stage of the root-knot nematode Meloidogyne hapla in nemato-suppressive and nemato-conducive soils

Nematode-suppressive soils are characterized by the ability of soil microbial communities to reduce populations plant-parasitic nematodes (PPN) either directly or inducing systemic resistance in plants. Various microorganisms have been recognized as antagonists PPN suppressive using culture-dependent and culture-independent methods. However, associations that form with nematode-conducive poorly studied. Here we drenched tomato rhizospheres suspensions from nine different followed their effects on plant growth root invasion infective second-stage juveniles (J2) northern root-knot nematode species Meloidogyne hapla . Based number invaded J2, four were determined nematode-suppressive, while five categorized nematode-conducive. To reveal bacteria attached J2 cuticle varying suppressiveness, incubated three conducive soils, analyzed J2-attached amplicon sequencing V3-V4 region 16S rRNA gene. Our results suggest origin had a major effect composition bacteria, highest bacterial abundance richness observed two soils. In addition, indicator sequence variants (ASVs) was associated but they very distinct profile. Further studies needed resolve complexity nemato-microbial interactions determine exact function nematode-attached role suppression protection. • Microbiomes uniquely affected J2. upon incubation Soil bacteria. Higher diversity found