School of Life Sciences, Ludong University, Yantai, 264025, China.
Key Laboratory of Integrated Pest Management on Tropical Crops, Ministry of Agriculture and Rural Affairs, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China.
Oecologia. 2020 Jul;193(3):665-676. doi: 10.1007/s00442-020-04703-y. Epub 2020 Jul 8.
Plant-soil feedbacks (PSFs) are plant-mediated changes to soil properties that ultimately influence plant performance, and can, thus, determine plant diversity, succession, and invasion. We hypothesized that PSFs influence invasion processes and that PSF mechanisms are largely driven by changes in soil properties produced by specific plant species. To test these hypotheses, we studied the effects of different soils collected from under common plant species on the growth of the invasive plant Phytolacca americana. We found that PSFs may interfere with invasion resistance because P. americana seedlings showed reduced growth (lower biomass) in soils collected from underneath some native species compared with soils collected from underneath P. americana and two non-native plants. We then selected eight co-occurring native and non-native plant species, and examined PSF dynamics and mechanisms in a pairwise conditioned soil greenhouse experiment. Plant species-specific conditioning effects regarding soil nutrients and enzyme activities were observed. Phytolacca americana had a high ability to use soil N, which may be related to its high invasion ability. Soil P was significantly lower in Quercus acutissima-conditioned soil, indicating that low P availability in Q. acutissima forests may enhance resistance to plant invasion. However, surprisingly, some native plants did not produce PSF effects that decreased the relative performance of invasive plants, nor did the invasive plants produce PSF effects that increased their own performance. We speculate that these PSF findings from greenhouse experiments cannot be extrapolated to field conditions because the litter and allelochemicals of some plants may be important for invasion resistance.
植物-土壤反馈（PSFs）是指植物介导的土壤性质变化，这些变化最终会影响植物的表现，从而决定植物的多样性、演替和入侵。我们假设 PSFs 会影响入侵过程，并且 PSF 机制主要是由特定植物物种产生的土壤性质变化驱动的。为了检验这些假设，我们研究了从常见植物物种下收集的不同土壤对入侵植物美洲商陆生长的影响。我们发现，PSFs 可能会干扰入侵抗性，因为与从美洲商陆和两种非本地植物下收集的土壤相比，P. americana 幼苗在从一些本地物种下收集的土壤中生长（生物量较低）。然后，我们选择了八种共同出现的本地和非本地植物物种，并在一个成对条件化土壤温室实验中研究了 PSF 的动态和机制。观察到了植物物种特异性对土壤养分和酶活性的调节作用。美洲商陆具有很高的利用土壤 N 的能力，这可能与其高入侵能力有关。在槲栎条件化的土壤中，土壤 P 显著降低，这表明在槲栎林中土壤 P 供应不足可能会增强对植物入侵的抵抗力。然而，令人惊讶的是，一些本地植物并没有产生降低入侵植物相对表现的 PSF 效应，入侵植物也没有产生提高自身表现的 PSF 效应。我们推测，这些来自温室实验的 PSF 发现不能外推到野外条件，因为一些植物的凋落物和化感物质可能对入侵抗性很重要。
