Effect of allelopathy on plant performance: a meta‐analysis

• Published in: Ecology letters Vol. 24; no. 2; pp. 348 - 362
• Main Authors: Zhang, Zhijie, Liu, Yanjie, Yuan, Ling, Weber, Ewald, van Kleunen, Mark, Gurevitch, Jessica
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01-02-2021
• Subjects: Allelopathy; Chemical interactions; Coexistence; Community structure; Crop; Domestication; Indigenous plants; interference competition; invasive species; Leachates; life history; Life span; Meta-analysis; Native species; Phylogenetics; Phylogeny; Plant communities; Plants; Residues; Soil; Soil conditions; soil microbes; Species; succession; Synthesis; Crop; interference competition; succession; life history; meta-analysis; phylogeny; invasive species; soil microbes
• ISSN: 1461-023X; 1461-0248
• DOI: 10.1111/ele.13627

Allelopathy (i.e. chemical interactions between plants) is known to affect individual performance, community structure and plant invasions. Yet, a quantitative synthesis is lacking. Here, we performed a meta‐analysis of 384 studies that measured allelopathic effects of one species (allelopathy plant) on another species or itself (test plant). Overall, allelopathy reduced plant performance by 25%, but the variation in allelopathy was high. The type of method affected the allelopathic effect: compared to leachates, allelopathy was more negative when residues of allelopathy plants were applied, and less negative when soil conditioned by allelopathy plants was applied. The negative effects of allelopathy diminished with study duration, and increased with concentrations of leachates or residues. Although allelopathy was not significantly related to lifespan, life form or domestication of the interacting plants, it became more negative with increasing phylogenetic distance. Moreover, native plants suffered more from leachates of naturalised alien plants than from leachates of other native plants. Our synthesis reveals that allelopathy could contribute to success of alien plants. The negative relationship between phylogenetic distance and allelopathy indicates that allelopathy might contribute to coexistence of closely related species (i.e. convergence) or dominance of single species.
Our meta‐analysis showed that allelopathy reduced plant performance by 25%, but the variation was high. The allelopathic effect was related to evolutionary history, indicating the role of allelopathy in species coexistence and plant invasion. We also reveal some major caveats in our current knowledge and provide suggestions for future studies.