Genomic and functional characterization of compost-derived bacteria identifies a candidate bioinoculant that influences tomato physiology and leaf metabolism

Kocuria rhizophila isolated from commercial municipal compost is linked to substrate-dependent tomato physiological changes, including leaf metabolic profile shifts at 33 days post inoculation.

• Why it matters: Intensive agriculture can disrupt soil microbial communities and plant-microbe interactions, and compost’s reservoir of culturable beneficial bacteria for bioinoculants remains largely unexplored.
• What they did: Six compost-derived bacterial strains were isolated and screened for plant growth-promoting traits; two isolates, Kocuria rhizophila and Glutamicibacter arilaitensis, underwent whole-genome sequencing and comparative functional analyses.
• The result: Inoculating tomato in soil, compost-amended soil, or sterile compost-amended soil showed K. rhizophila effects primarily driven by substrate type, with specific effects at 33 days and a trend toward increased dry biomass in sterile compost.