Biotic Interactions in Invasive Plant Dynamics

Invasive plants succeed or fail largely through their interactions with other organisms. These biotic interactions span enemy release—where exotic species escape specialised herbivores and pathogens—to biotic resistance, where native herbivores and pathogens suppress newcomers. Mutualistic partnerships, notably with mycorrhizal fungi and pollinators, can enhance invader establishment by improving nutrient acquisition and reproduction. Competitive interactions also play a critical role: invasive species may overcome classic competition–colonisation trade-offs by mounting high propagule pressure and exhibiting superior growth or resource-use efficiency. Allelopathic chemicals released by some invaders further disrupt native plant communities and soil microbial networks, reinforcing invasion success. Coevolutionary processes may emerge locally as native species adapt to persistent invaders, yet rapid evolution in invaders can counterbalance native defences. The global significance of these dynamics is evident in altered ecosystem services, from nutrient cycling to habitat provision, and in economic impacts on agriculture and forestry. Practical management actions increasingly target biotic interactions—for example, restoration of native herbivore guilds or inoculation with native soil microbes—to re-establish ecological resistance. Concrete examples include control of aquatic invaders by reintroduction of specialist herbivores and restoration of native mycorrhizal networks to limit terrestrial invaders. A holistic understanding of these interlinked biotic forces is essential for predicting invasion trajectories and designing effective mitigation strategies.

Research from Nature Portfolio

Recent studies have elucidated how modern introductions can drive native extinctions by disrupting coexistence mechanisms. One key work demonstrates that high propagule pressure, enemy release and enhanced competitive ability allow some invaders to overcome traditional competition–colonisation trade-offs. Using mechanistic metacommunity models, the study shows how human-mediated introductions—involving repeated, large-scale propagule input and reduced enemy pressure—can tip community dynamics towards competitive displacement of natives. This research highlights that invader-driven extinction debts are most severe when combined with other anthropogenic stressors, emphasising the need to integrate biotic interactions and propagule management in conservation policy.

Biotic Interactions in Invasive Plant Dynamics publication trend

The graph below shows the total number of articles in biotic interactions in invasive plant dynamics across all publications each year (not limited to Nature Index journals).

Technical terms

Enemy release hypothesis (ERH): Proposal that invaders thrive because they escape specialised herbivores and pathogens present in their native range.

Biotic resistance: Suppression of introduced species growth by native predators, herbivores or pathogens.

Competition–colonisation trade-off: Ecological principle that species balance between competitive ability in established communities and colonisation of new sites.

Propagule pressure: Quantity, frequency and quality of organisms introduced to a new habitat, influencing invasion success.

Mycorrhizal mutualism: Symbiotic association between plant roots and fungi that enhances nutrient uptake and can facilitate or hinder invasions.

References

1. Among‐population variation in drought responses is consistent across life stages but not between native and non‐native ranges. New Phytologist (2024).
2. A mechanistic framework of enemy release. Ecology Letters (2023).
3. Active defense strategies for invasive plants may alter the distribution pattern of pests in the invaded area. Frontiers in Plant Science (2024).
4. Introduced species that overcome life history tradeoffs can cause native extinctions. Nature Communications (2018).