Allelopathy is pervasive in invasive plants

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.

Long-Term Giant Hogweed Invasion Contributes to the Structural Changes of Soil Nematofauna

“…Our study did reveal the negative impact of Hm invasion on the native plant species, mainly grasses such as D. glomerata, P. pratensis, T. flavescens, and Festuca sp., which disappeared in the invaded plots, confirming the results by [46] from the abandoned grassland habitat invaded by giant hogweed in Germany. This suggests that allelopathy (production of allelochemicals that inhibit the growth of native plants) could be one of the mechanisms of Hm invasion success, in agreement with current phylogenetic analysis by [47], who revealed that the majority of the 524 invasive plant species analyzed produced allelochemicals with the potential to negatively affect native plant performance. Nevertheless, the most frequent native tall forb in relevés with Hm was U. dioica, which is itself a strong and high-growing competitor (C-strategist) according to [48], or H. tuberosus, whose cover increased at the end of the vegetation cycle of giant hogweed (autumn).…”

Diversity of Resident Plant Communities Weakens Their Allelopathic Resistance Against Alien and Native Invaders

“…Baker 1974), that the high competitive ability of some invasive plants could be achieved by suppression of germination and growth of neighboring plants by allelochemicals. In support of this idea, Kalisz et al (2021) recently showed that in their database of 524 invasive plant species at least half have known allelopathic effects on other species. The idea that allelopathy may play a role in invasion success is also part of the novel-weapons hypothesis, which poses that some alien plants have become invasive due to the production of chemical compounds that are toxic to the naïve native plants (Callaway and Ridenour, 2004).…”

Invasion‐induced root–fungal disruptions alter plant water and nitrogen economies

“…While only recently investigated as a mechanism of invasion-induced impacts on belowground dynamics, many of the most invasive plants alter soil microbiome abundance and diversity and disrupt plant-microbial interactions (Reinhart & Callaway 2006;Dawson & Schrama 2016;Kalisz et al 2020). Invasion-induced changes in soil microbiomes are driven by non-native plant host specificity in microbial associations (Husband et al 2002;Vandenkoornhuyse et al 2002), altered plant diversity (Kivlin & Hawkes 2011), altered plant-soil feedbacks (van der Putten 2010) and direct toxicity of soil microbes via the production of allelochemicals (Hierro & Callaway 2003).…”

“…While only recently investigated as a mechanism of invasion‐induced impacts on belowground dynamics, many of the most invasive plants alter soil microbiome abundance and diversity and disrupt plant–microbial interactions (Reinhart & Callaway 2006; Dawson & Schrama 2016; Kalisz et al . 2020). Invasion‐induced changes in soil microbiomes are driven by non‐native plant host specificity in microbial associations (Husband et al .…”