The Specific Impacts of Allelopathy and Resource Competition from on the Growth of Three Plant Species in Northern China.

Plant interference is a key factor influencing plant coexistence and species composition. The two primary forms of plant interference-allelopathy and resource competition-are often difficult to separate. This study conducted an outdoor pot experiment to quantify the distinct contributions of resource competition and allelopathy of on seedling growth of three species: , , and . The index of relative neighbor effect () was used to quantify the overall effect of plant interference, while the inhibition rates () of resource competition and allelopathy were utilized to determine the specific contributions of allelopathy and resource competition from . on the growth of target plant species. The interference effect of . was found to be species-specific. The allelopathic effect of . played a major role in inhibiting the belowground biomass of . (23.97%) and . (58.27%), while allelopathy and resource competition from . promoted the belowground biomass (45.12%) and aboveground biomass (46.63%) of . , respectively. The combined effect of allelopathy and resource competition from . significantly affected the aboveground biomass of . and . , as well as the belowground biomass of . and . . These findings contribute to a better understanding of the patterns and mechanisms of plant species composition and its relationship with grazing intensity in this grassland ecosystem.