Plants were traditionally seen as rather passive actors in their environment, interacting with each other only in so far as they competed for the same resources. In the last 30 years, this view has been spectacularly overturned, with a wealth of evidence showing that plants actively detect and respond to their neighbours. Moreover, there is evidence that these responses depend on the identity of the neighbour, and that plants may cooperate with their kin, displaying social behaviour as complex as that observed in animals. These plant–plant interactions play a vital role in shaping natural ecosystems, and are also very important in determining agricultural productivity. However, in terms of mechanistic understanding, we have only just begun to scratch the surface, and many aspects of plant–plant interactions remain poorly understood. In this review, we aim to provide an overview of the field of plant–plant interactions, covering the communal interactions of plants with their neighbours as well as the social behaviour of plants towards their kin, and the consequences of these interactions. We particularly focus on the mechanisms that underpin neighbour detection and response, highlighting both progress and gaps in our understanding of these fascinating but previously overlooked interactions.

中文翻译：

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朋友、邻居和敌人：植物群落和社会生物学概述

传统上，植物在其环境中被视为相当被动的参与者，只有在它们竞争相同的资源时才会相互交互。在过去的 30 年里，这一观点被惊人地推翻，大量证据表明植物会主动检测并响应邻居。此外，有证据表明，这些反应取决于邻居的身份，植物可能会与其亲属合作，表现出与在动物身上观察到的一样复杂的社会行为。这些植物与植物之间的相互作用在塑造自然生态系统方面发挥着至关重要的作用，在决定农业生产力方面也非常重要。然而，就机理理解而言，我们才刚刚开始触及皮毛，植物-植物相互作用的许多方面仍然知之甚少。在这次审查中，我们的目标是提供植物与植物相互作用领域的概述，涵盖植物与其邻居的公共相互作用以及植物对其亲属的社会行为，以及这些相互作用的后果。我们特别关注支持邻居检测和响应的机制，突出了我们对这些引人入胜但以前被忽视的交互的理解方面的进展和差距。