College of Resources and Environmental Sciences, China Agricultural University, Beijing, China.
Department of Biological Sciences, Eastern Illinois University, Charleston, Illinois, USA.
Plant Cell Environ. 2021 Dec;44(12):3479-3491. doi: 10.1111/pce.14083. Epub 2021 May 28.
Species interactions and mechanisms affect plant coexistence and community assembly. Despite increasing knowledge of kin recognition and allelopathy in regulating inter-specific and intra-specific interactions among plants, little is known about whether kin recognition mediates allelopathic interference. We used allelopathic rice cultivars with the ability for kin recognition grown in kin versus non-kin mixtures to determine their impacts on paddy weeds in field trials and a series of controlled experiments. We experimentally tested potential mechanisms of the interaction via altered root behaviour, allelochemical production and resource partitioning in the dominant weed competitor, as well as soil microbial communities. We consistently found that the establishment and growth of paddy weeds were more inhibited by kin mixtures compared to non-kin mixtures. The effect was driven by kin recognition that induced changes in root placement, altered weed carbon and nitrogen partitioning, but was associated with similar soil microbial communities. Importantly, genetic relatedness enhanced the production of intrusive roots towards weeds and reduced the production of rice allelochemicals. These findings suggest that relatedness allows allelopathic plants to discriminate their neighbouring collaborators (kin) or competitors and adjust their growth, competitiveness and chemical defense accordingly.
物种相互作用和机制影响植物共存和群落组装。尽管人们越来越了解亲缘识别和化感作用在调节植物种间和种内相互作用方面的作用，但对于亲缘识别是否介导化感干扰知之甚少。我们使用具有亲缘识别能力的化感水稻品种，在亲缘和非亲缘混合物中种植，以确定它们对田间杂草的影响，并进行了一系列对照实验。我们通过改变根行为、化感物质产生和优势杂草竞争者的资源分配，以及土壤微生物群落，实验性地测试了这种相互作用的潜在机制。我们一致发现，与非亲缘混合物相比，亲缘混合物更能抑制稻田杂草的建立和生长。这种效应是由亲缘识别引起的，它诱导了根的放置变化，改变了杂草的碳氮分配，但与相似的土壤微生物群落有关。重要的是，遗传相关性增强了向杂草侵入性根的产生，并减少了水稻化感物质的产生。这些发现表明，亲缘关系使化感植物能够识别其邻近的合作者（亲缘）或竞争者，并相应地调整其生长、竞争力和化学防御。
