Labouyrie, M. | bioRxiv Science

bioRxiv2026

Compost from urban biowaste shapes the bacterial community and its functional traits in the rhizosphere of tomato plants

Industrial compost derived from urban biowaste is a sustainable biofertilizer made from food waste and plant matter. It has long been used as a fertilizer in agriculture and horticulture for its rich nutrient content. However, the composition of the microbiota in industrial biowaste compost has been studied only partially, and the effects of this bacterial community on soil, rhizosphere, and plant root communities have received limited attention. In this study, we conducted community and functional analyses to examine how the microbiota in biowaste compost influences bacterial diversity, community composition, and metabolic potential in tomato plants, compared with plants fertilized with conventional, unsustainable chemical fertilizer. Source contribution analysis tracking bacterial taxa indicated a significant contribution of compost-derived taxa to the soil, rhizosphere, and roots. The community analysis revealed distinct clustering by fertilizer type, with biowaste compost promoting a unique, more diverse rhizosphere community, enriched in Firmicutes species. Functional analysis highlighted increased microbial pathways in the rhizosphere treated with biowaste compost, including enzymes for cellulolytic and xylanolytic activity, nitrogenase, phytase, and 1-ACC deaminase. Overall, food-derived industrial biowaste compost enhances bacterial diversity and the predicted functional and plant growth-promoting potential in the rhizosphere of tomato plants, underscoring its potential as a sustainable biofertilizer that supports soil health, microbial biodiversity, and crop productivity.

plant biology↗

bioRxiv2023

Soil health is linked to primary productivity across Europe

A healthy soil is at the core of sustainable management and policy, but its importance for plant productivity across environmental gradients and land-use types remains poorly understood. To address this gap, we conducted a pan-European field study including 588 sites from 27 countries to investigate the link between soil health and primary productivity across three major land-use types: woodlands, grasslands, and croplands. We found that mean soil health (a composite index based on soil properties, biodiversity, and plant disease control) in woodlands was 31.4% higher than in grasslands, and 76.1% higher than in croplands. Soil health was positively linked to cropland and grassland productivity at the continental scale. Woodland productivity was best explained by climate. Among microbial diversity indicators, we observed a positive association between the richness of Acidobacteria, Firmicutes, and Proteobacteria and primary productivity. Among microbial functional groups, we found that nitrogen-fixing bacteria and mycorrhizal fungi positively related to primary productivity in croplands and grasslands, while plant pathogens showed a negative relationship. Together, our results point to the importance of soil biodiversity and soil health for maintaining primary productivity across contrasting land-use types.

ecology↗