Allelopathy research on the continuous cropping problem of poplar (populus)

The mechanism of decline in continuous plantations is currently a popular research topic in forestry. Continuous cropping is a common obstacle in poplar production and management, and maintaining productivity is a technical challenge. Recent studies have shown that continuous cropping of poplars leads to a reduction in biomass, but there is a lack of information summarizing the effects of plant secondary compounds on belowground interactions. This paper explores the allelopathic phenomenon, which refers to the inhibitory or promoting effects of poplar tissue extracts on plants. The paper also considers the environmental behaviors of allelochemicals derived from poplars, including their secretion, degradation, adsorption, retention, and phytotoxicity. A conceptual model of the autotoxicity mechanism of continuous cropping poplar is proposed from three aspects: microorganisms, soil enzymes, and nutrient changes, with the goal of overcoming poplar autotoxicity. Finally, the research results and potential application prospects of biotechnological methods related to the allelopathic effects of poplar are presented.