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.

中文翻译：

---

化感作用对植物生长的影响：荟萃分析

已知化感作用（即植物之间的化学相互作用）会影响个体的行为，群落结构和植物入侵。然而，缺乏定量综合。在这里，我们对384项研究进行了荟萃分析，这些研究测量了一个物种（化感作用植物）对另一物种或自身（测试植物）的化感作用。总体而言，化感作用使植物性能降低了25％，但化感作用的变化很大。方法的类型会影响化感作用：与渗滤液相比，施用化感病植物的残留物时化感作用较阴性，而应用化感病植物处理的土壤时化感作用较阴性。化感作用的负面影响随着研究时间的延长而减少，并随着渗滤液或残留物的浓度而增加。尽管化感作用与相互作用植物的寿命，生命形式或驯化没有显着关系，但随着系统发生距离的增加，化感作用变得更加不利。此外，天然植物受自然化外来植物浸​​出液的损害要比其他天然植物浸出液所遭受的损害更大。我们的综合表明，化感作用可能有助于外来植物的成功。系统发育距离与化感作用之间的负相关关系表明，化感作用可能有助于密切相关物种的共存（即会聚）或单个物种的优势。我们的综合表明，化感作用可能有助于外来植物的成功。系统发育距离与化感作用之间的负相关关系表明，化感作用可能有助于密切相关物种的共存（即会聚）或单个物种的优势。我们的综合表明，化感作用可能有助于外来植物的成功。系统发育距离与化感作用之间的负相关关系表明，化感作用可能有助于密切相关物种的共存（即会聚）或单个物种的优势。