Abstract:

In this study, different concentrations of Phoebe bournei(Hemsl.) Yang litter branch and leaf extracts were tested to treat P. bournei seeds and seedlings. Seed germination, seedling growth, and physiological indices were measured. Results showed that: (1) Extracts of P. bournei litter branches and leaves inhibited seed germination at all concentrations. Inhibition intensity was enhanced with the increase in the concentration of the two extracts. However, inhibition intensity of the litter branches was greater than that of the litter leaves. Notably, inhibition intensity was branch>leaf regarding the germination index; leaf>branch regarding root bud length; and branch>leaf regarding comprehensive allelopathy. (2) Litter branch extracts inhibited the growth of one-year-old P. bournei seedlings, while litter leaf extracts showed “low promoting and high inhibiting” effects. High concentrations of the extracts seriously inhibited the growth of seedlings, causing many leaves to develop spots, atrophy, and yellow color. (3) The effects of litter extracts on P. bournei seedling physiology were complex. High-concentration extracts disturbed the physiological of seedlings, causing abnormalities in the antioxidant system, significant increases in malondialdehyde (MDA) content, and increases in cell membrane permeability in leaves, resulting in an abnormal growth state. Long-term exposure to low-concentration extracts induced stress in the plants and caused changes in related physiological indices.

摘要：

采用不同浓度凋落枝、凋落叶浸提液处理闽楠（Phoebe bournei（Hemsl.） Yang）种子和幼苗，测定其萌发、生长及生理指标。结果显示：（1）整体上，闽楠凋落枝和凋落叶浸提液对自身种子萌发表现为抑制作用，且抑制作用均随两种浸提液浓度升高而增强，且凋落枝抑制作用大于凋落叶。在发芽指标上，抑制强度表现为枝>叶；在根芽长度上，抑制强度表现为叶>枝；综合化感效应表现为枝>叶。（2）凋落枝浸提液对一年生闽楠幼苗生长指标表现为抑制作用，凋落叶浸提液表现为“低促高抑”的效应。高浓度浸提液可严重抑制幼苗生长，并造成大量叶片出现斑点、萎缩和枯黄；（3）闽楠凋落物浸提液对闽楠幼苗生理的影响较为复杂，高浓度浸提液可造成幼苗生理紊乱，导致其抗氧化系统异常，引起丙二醛含量显著增加，叶片细胞膜通透性增大，导致植株处于非正常生长状态，而长期浇灌低浓度浸提液也会使植物处于胁迫状态而引起相关生理指标变化。