Abstract Invasive species utilize a wide array of trait strategies to establish in novel ecosystems. Among these traits is the capacity to produce allelopathic compounds that can directly inhibit neighboring native plants or indirectly suppress native plants via disruption of beneficial belowground microbial mutualisms, or altered soil resources. Despite the well-known prevalence of allelopathy among plant taxa, the pervasiveness of allelopathy among invasive plants is unknown. Here we demonstrate that the majority of the 524 invasive plant species in our database produce allelochemicals with the potential to negatively affect native plant performance. Moreover, allelopathy is widespread across the plant phylogeny, suggesting that allelopathy could have a large impact on native species across the globe. Allelopathic impacts of invasive species are often thought to be present in only a few plant clades (e.g., Brassicaceae). Yet our analysis shows that allelopathy is present in 72% of the 113 plant families surveyed, suggesting that this ubiquitous mechanism of invasion deserves more attention as invasion rates increase across the globe.
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The Ecological Importance of Allelopathy
Allelopathy (i.e., chemical interaction among species) was originally conceived
as inclusive of positive and negative effects of plants on other plants,
and we adopt this view. Most studies of allelopathy have been phenomenological,
but we focus on studies that have explored the ecological significance
of this interaction. The literature suggests that studies of allelopathy have
been particularly important for three foci in ecology: species distribution,
conditionality of interactions, and maintenance of species diversity. There
is evidence that allelopathy influences local distributions of plant species
around the world. Allelopathic conditionality appears to arise through
coevolution, and this is a mechanism for plant invasions. Finally, allelopathy
promotes species coexistence via intransitive competition, modifications of
direct interactions, and (co)evolution. Recent advances additionally suggest
that coexistence might be favored through biochemical recognition. The
preponderance of phenomenological studies notwithstanding, allelopathy
has broad ecological consequences.
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- Award ID(s):
- 1757351
- PAR ID:
- 10329043
- Date Published:
- Journal Name:
- Annual review
- Volume:
- 52
- ISSN:
- 0113-0102
- Page Range / eLocation ID:
- 25-45
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1146/annurev-ecolsys-051120- 030619
