Sophora alopecuroides is known to produce relatively large amounts of alkaloids; however, their ecological consequences remain unclear. In this study, we evaluated the allelopathic potential of the main alkaloids, including aloperine, matrine, oxymatrine, oxysophocarpine, sophocarpine, sophoridine, as well as their mixture both in distilled H₂O and in the soil matrix. Our results revealed that all the alkaloids possessed inhibitory activity on four receiver species, i.e., Amaranthus retroflexus, Medicago sativa, Lolium perenne and Setaria viridis. The strength of the phytotoxicity of the alkaloids was in the following order: sophocarpine > aloperine > mixture > sophoridine > matrine > oxysophocarpine > oxymatrine (in Petri dish assays), and matrine > mixture > sophocarpine > oxymatrine > oxysophocarpine > sophoridine > aloperine (in pot experiments). In addition, the mixture of the alkaloids was found to significantly increase the IAA content, MDA content and POD activity of M. sativa seedlings, whereas CTK content, ABA content, SOD activity and CAT activity of M. sativa seedlings decreased markedly. Our results suggest S. alopecuroides might produce allelopathic alkaloids to improve its competitiveness and thus facilitate the establishment of its dominance; the potential value of these alkaloids as environmentally friendly herbicides is also discussed.

Introduction: Global warming exhibits asymmetric patterns (differential day–night warming rates), yet its effects on early plant regeneration and physiological adaptation remain unclear. This study aimed to investigate the effects of different warming regimes on seedling emergence, growth, and physiological traits of Sophora alopecuroides , in order to assess its invasive potential under climate warming scenarios. Methods: A controlled experiment was conducted with symmetric warming, daytime warming (asymmetric), nocturnal warming (asymmetric), and a control treatment. Measurements included seedling emergence time and final emergence percentage, morphological traits (plant height, root length, leaf area), biomass allocation (stem dry mass, root fresh mass, root–shoot ratio, specific root length, specific leaf area), and physiological indices (antioxidant system activity). Results: Emergence: Symmetric warming significantly advanced the onset of emergence, but none of the warming treatments altered final emergence relative to the control. Growth: Asymmetric warming induced stronger stimulation of leaf area than nocturnal warming; excessively high night-time temperatures suppressed plant height and markedly inhibited root elongation while reducing leaf area. Symmetric warming significantly increased stem dry mass, whereas asymmetric warming produced the highest root fresh mass among all treatments. Biomass allocation: Diurnal asymmetric warming markedly shifted biomass allocation patterns and morphological characteristics; it inhibited root elongation while increasing root biomass accumulation, resulting in an elevated root–shoot ratio but reduced specific root length and specific leaf area. Physiological response: Under diurnal asymmetric warming, plants activated their antioxidant systems to mitigate oxidative damage. Discussion: Asymmetric warming (particularly diurnal asymmetry) may enhance the invasive potential of S. alopecuroides by promoting biomass accumulation and altering resource allocation strategies (e.g., increased root–shoot ratio and activation of antioxidant defense). These adaptive mechanisms might facilitate its rapid spread in the region under climate change scenarios.

This study examined four forest stands (Pseudotsuga gaussenii Flous, Quercus glauca Thunb., Pinus taiwanensis Hayata and Rhododendron simiarum Hance forests) in the Huaiyu Mountain Range at the Jiangxi–Zhejiang border in China and systematically compared their litter stocks, water-holding characteristics, soil hydro-physical properties, and infiltration characteristics through field investigation, the cutting-ring method, and the indoor soaking method. The results were as follows: (1) The total litter stock ranged from 4.64 to 8.35 t·ha⁻¹, being highest in the R. simiarum forest and lowest in the Q. glauca forest. (2) The litter maximum water-holding capacity (2.92–5.92 t·ha⁻¹) and effective water-retention capacity (1.56–3.30 t·ha⁻¹) differed significantly among stands (p < 0.05), with the P. gaussenii forest performing well and the P. taiwanensis forest performing the worst. (3) In the 0–30 cm soil layer, bulk density increased with depth, while total porosity and water-holding capacity decreased significantly (p < 0.05), and the infiltration rate showed a power-function relationship with time (R² > 0.95); among the four forest types, the R. simiarum forest exhibited the highest maximum and capillary soil water-holding capacities, the Q. glauca forest had the strongest infiltration and runoff-interception capacity, and the P. taiwanensis forest had the weakest overall soil hydrological performance. (4) Semi-decomposed litter had a significantly higher maximum water-holding capacity than undecomposed litter, and litter water-holding capacity and water absorption rate showed logarithmic and power-function relationships with soaking time, respectively (both R² > 0.90). A comprehensive evaluation using the entropy weight method identified the P. gaussenii and Q. glauca forests as the superior stand types. These results provide scientific guidance for tree species selection in forest transformation and for sustainable forest management in this region.