Nematode-Trapping Fungi and Their Ecological Interactions

Nematode-trapping fungi represent a unique guild of soil-dwelling organisms that have evolved specialised devices to seize and consume nematodes. These carnivorous fungi exhibit a remarkable lifestyle switch from saprotrophy to predation, constructing adhesive nets, knobs or constricting rings in response to nematode cues. Predatory success is governed by complex signalling pathways: nematode-derived ascarosides trigger G-protein-coupled receptors, reprogramming fungal metabolism and inducing trap development, while bacterial metabolites such as urea and its derivative ammonia can likewise stimulate trap formation. Some species produce volatile morphogens—for example, methyl-salicylic acid type compounds—that serve both as chemoattractants and as regulators of trap timing. Beyond direct predation, nematode-trapping fungi occupy critical ecological niches by regulating nematode populations, contributing to nutrient cycling, and interacting with soil microbiomes. Soil bacteria may enhance or inhibit trap formation, illustrating the multilayered interkingdom dialogues that underpin fungal predation. These interactions have global significance for sustainable agriculture, as nematode-trapping fungi offer promising biocontrol agents against plant-parasitic nematodes without the drawbacks of chemical nematicides.

Research from Nature Portfolio

Recent studies have demonstrated that a dual-localised G-protein-coupled receptor in Arthrobotrys flagrans recognises nematode ascarosides at the cell surface and within mitochondria, thereby synchronising trap formation with heightened respiratory activity. Investigations into Duddingtonia flagrans have identified a polyketide-derived methyl-salicylic acid isomer that functions as both a morphogen controlling the spatial patterning of traps and a volatile attractant to lure Caenorhabditis elegans. In addition, research into bacterial–fungal–nematode triads has shown that soil bacteria release urea, which is converted to ammonia within the fungus to induce a predatory lifestyle switch, underscoring the importance of multi-kingdom chemical signalling in regulating fungal carnivory.

Nematode-Trapping Fungi and Their Ecological Interactions publication trend

The graph below shows the total number of articles in nematode-trapping fungi and their ecological interactions across all publications each year (not limited to Nature Index journals).

Technical terms

Nematode-trapping fungi (NTF): Carnivorous fungi that capture nematodes using specialised trapping structures.

Ascarosides: Small-molecule pheromones secreted by nematodes that serve as chemical cues for fungi.

G-protein-coupled receptor (GPCR): Membrane-embedded receptors that transduce extracellular signals into cellular responses.

Secretome: The entire complement of proteins secreted by a cell or organism during interaction with its environment.

Conidial traps: Predatory structures formed directly from asexual spores (conidia) enabling nematode capture under adverse conditions.

Metagenomic sequencing: High-throughput analysis of genetic material extracted from environmental samples to characterise microbial communities.

References

1. GprC of the nematode-trapping fungus Arthrobotrys flagrans activates mitochondria and reprograms fungal cells for nematode hunting. Nature Microbiology (2024).
2. Key processes required for the different stages of fungal carnivory by a nematode-trapping fungus. PLOS Biology (2023).
3. Induction of conidial traps in the nematode-trapping fungus Drechslerella dactyloides by soil microbes. mSystems (2025).
4. Fungi–Nematode Interactions: Diversity, Ecology, and Biocontrol Prospects in Agriculture. Journal of Fungi (2020).
5. Bacteria can mobilize nematode-trapping fungi to kill nematodes. Nature Communications (2014).