Biology subjects

van der Heijden, M. G. A.

Publications and source records attributed to van der Heijden, M. G. A..

4 recordsLinked to original sources

bioRxiv2025

Diverse crop rotations off-set yield-scaled nitrogen losses via denitrification

Denitrification, a major source of gaseous nitrogen (N) emissions from agricultural soils, is influenced by management. Practices promoting belowground diversity are suggested to support sustainable agriculture, but their ability to modulate gaseous N-losses via denitrification remains inconclusive. To fill this knowledge gap, we sampled 106 cereal fields spanning a 3,000 km North-South gradient across Europe and compiled 56 associated climatic, soil, microbial and management variables. We found that increased denitrification was associated with higher proportion of time with crop cover over the last ten years. Denitrification rates were best predicted by microbial biomass and microbial functional guilds involved in N cycling, in particular denitrification. We also show that several diversification practices affect the variation in denitrification predictors, suggesting a trade-off between agricultural diversification and gaseous N-losses via denitrification. However, increased crop diversity in rotations improved yield-scaled denitrification, highlighting the potential of this practice to minimize N losses while contributing to sustainable food production.

ecology↗

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↗

bioRxiv2023

A tripartite bacterial-fungal-plant symbiosis in the mycorrhiza-shaped microbiome drives plant growth and mycorrhization

Plant microbiomes play crucial roles in nutrient cycling and plant growth, and are shaped by a complex interplay between plants, microbes, and the environment. The role of bacteria as mediators of the 400-million-year-old partnership between the majority of land plants and, arbuscular mycorrhizal (AM) fungi is still poorly understood. Here we test whether AM hyphae-associated bacteria influence the success of the AM symbiosis. Using partitioned microcosms containing field soil, we discovered that AM hyphae and roots selectively assemble their own microbiome from the surrounding soil. In two independent experiments, we identified several bacterial genera, including Devosia, that are consistently enriched on AM hyphae. Subsequently, we isolated 144 pure bacterial isolates from a mycorrhiza-rich sample of extraradical hyphae and isolated Devosia sp. ZB163 as root and hyphal colonizer. We show that this AM-associated bacterium synergistically acts with mycorrhiza on the plant root to strongly promote plant growth, nitrogen uptake, and mycorrhization. Our results highlight that AM fungi do not function in isolation and that the plant-mycorrhiza symbiont can recruit beneficial bacteria that support the symbiosis.

microbiology↗

bioRxiv2023

AMF-SporeChip provides new insights into arbuscular mycorrhizal fungal pre-symbiotic hyphal growth dynamics at the cellular level.

O_LIArbuscular mycorrhizal fungi (AMF) form symbiotic associations with the majority of land plants and deliver a wide range of soil-based ecosystem services. Due to their conspicuous belowground lifestyle in a dark environment surrounded by soil particles, much is still to be learned about the influence of environmental (i.e., physical) cues on spore germination, hyphal morphogenesis and hyphopodium formation in AMF. C_LIO_LITo fill existing gaps in AMF knowledge, we developed a new microfluidic platform - termed the AMF-SporeChip - to immobilise Rhizophagus and Gigaspora spores and confront pre-symbiotic hyphae with physical obstacles. In combination with timelapse microscopy, the fungi could be examined at the cellular level and in real-time. C_LIO_LIThe AMF-SporeChip allowed us to acquire movies with unprecedented visual clarity and therefore identify various exploration strategies of AMF pre-symbiotic hyphae. We witnessed anastomosis formation involving directed hyphal growth in a "stop-and-go" manner, yielding visual evidence of pre-anastomosis signalling and decision-making. Remarkably, we also revealed a so-far undescribed reversible cytoplasmic retraction as part of a highly dynamic space navigation. C_LIO_LIOur findings demonstrated how AMF employ an intricate mechanism of space searching, involving reversible cytoplasmic retraction, branching and directional changes. In turn, the AMF-SporeChip is expected to open many future frontiers for AMF research. C_LI

microbiology↗