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本文从作物种内互作和种间互作以及直接化感作用和间接化感作用两个维度重点阐述了近年来中国在作物化感作用类型的研究及其新进展,以期与同行分享该领域的研究成果和经验.早在1984年就有作物化感作用的相关报道,近年来取得了很大的进展.作物化感作用的概念也延伸到植物-土壤-微生物相互之间的化感作用,作物种植体系中存在的偏害、自毒和促进等现象均与此有关.最近的研究表明,供体植物通过触发防御基因的表达,使代谢产物(化感物质)释放到环境中,尤其是土壤环境中作物的根系等对靶标植物(如杂草)的胁迫做出响应,从而在栽培系统中产生化感偏害或化感偏利现象.根据作用对象的不同,作物化感偏害和偏利现象分为种间和种内的相互作用两种类型.种间作用包括抑制和互惠作用,化感物质的种类、含量及其生物效应决定了其对邻近物种的化感效应;种内作用包括促进和自毒作用,即化感正效应和化感负效应.化感正效应或负效应均与根系分泌物介导的根际土壤微生物组成和结构的变化有关.连续单一化种植导致的病原菌增多、有益菌减少,土壤微生物结构失衡可引起化感负效应.这种微生物结构失衡不可避免地导致土壤养分封存、土壤酸化和土传病害发生等,从而导致作物产量和品质下降.化感正效应则与之相反,连作促进了有益菌群的增加和致病微生物的减少,提高了微生物多样性,从而改善土壤微生境,提高作物产量和品质.因此,研究根际土壤微生物的结构与功能,合理调控作物根际生境以保证其高产优质,促进农业可持续发展,将是今后研究的重点.“,”In this review, we present details of recent advances in research on different types and action modes of crop allelopathy in China. In particular, we focus not only on direct and indirect allelopathy but also on intra- and interspecific interactions, with the aim of informing international peers of the ongoing developments in this field. The term crop allelopathy was first defined in 1984, and since that time, substantial progress has been made in this area, during which the concept of crop allelopathy has been broadened to encompass plant-soil-microbial interactions, including amensalism, autotoxicity, and facilitation in cropping systems. Recent studies have revealed that donor plants are able to trigger the expression of defense-related genes, resulting in the release of specific metabol-ites (allelochemicals) into the environment. In particular, allelopathic crops have been found to secrete these chemicals into the soil environment via root exudation in response to stresses induced by target plants (such as weeds), which in turn results in allelopathic amensalism and allelopathic commensalisms in cropping systems. The amensalistic and commensalistic components of crop allelo-pathy can be further divided into intra- and interspecific interactions based on mode of action. Interspecific interactions involve the in-hibitory or facilitative effects of donors on recipient plants, depending on the types, concentrations, and bio-activity of allelochemic-als; whereas intraspecific interactions include auto-promotive and auto-toxic effects, which can be either positive or negative. The current consensus indicates that both positive and negative allelopathic interactions are mediated via changes in rhizosphere soil mi-crobial composition and structure in response to root allelopathic secretions. In this regard, however, there is often an imbalance in the composition of soil microbial communities, which is largely attributable to an increase in pathogen populations and reduction in those of beneficial bacteria as a consequence of consecutive monoculture cropping. Such imbalances inevitably lead to three undesirable outcomes in continuous cropping systems, namely, soil nutrient sequestration, soil acidification, and the outbreak of soil-borne dis-eases, thereby resulting in reduced crop yields and quality. Conversely, in the case of positive allelopathic interactions, continuous cropping can contribute to promoting increases in microbial diversity mainly as a consequence of increments in the populations of be-neficial bacteria and corresponding reductions in pathogenic microorganisms, thereby enhancing soil micro-habitats, and thus increas-ing crop yield and quality. Given these responses, a key priority for future research is more in-depth studies of the structure and func-tion of rhizosphere microbial communities, and appropriate modification of rhizosphere habitats, with the aim of producing high-yielding good quality crops for sustainable agricultural development.