Saar Sirgi, Semchenko Marina, Barel Janna M, De Deyn Gerlinde B
1Department of Soil Quality, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands.
2Department of Botany, Institute of Ecology and Earth Sciences, University of Tartu, 40 Lai St, 51005 Tartu, Estonia.
Plant Soil. 2018;428(1):253-264. doi: 10.1007/s11104-018-3667-9. Epub 2018 May 11.
Plants affect the soil environment via litter inputs and changes in biotic communities, which feed back to subsequent plant growth. Here we investigated the individual contributions of litter and biotic communities to soil feedback effects, and plant ability to respond to spatial heterogeneity in soil legacy.
We tested for localised and systemic responses of to soil biotic and root litter legacy of seven grassland species by exposing half of a root system to control soil and the other half to specific inoculum or root litter.
Soil inoculation triggered a localised reduction in root length while litter locally increased root biomass independent of inoculum or litter species identity. Nodule formation was locally suppressed in response to soil conditioned by another legume ( and showed a trend towards systemic reduction in response to conspecific soil. litter also caused a systemic response with thinner roots produced in the part of the root system not directly exposed to the litter.
Spatial heterogeneity in root litter distribution and soil communities generate distinct local and systemic responses in root morphology and nodulation. These responses can influence plant-mutualist interactions and nutrient cycling, and should be included in plant co-existence models.
植物通过凋落物输入和生物群落变化影响土壤环境，进而反馈影响后续植物生长。在此，我们研究了凋落物和生物群落对土壤反馈效应的各自贡献，以及植物对土壤遗留物空间异质性的响应能力。
通过将一半根系暴露于对照土壤，另一半暴露于特定接种物或根系凋落物，测试了7种草地物种对土壤生物和根系凋落物遗留物的局部和系统响应。
土壤接种导致根长局部减少，而凋落物则使根生物量局部增加，且与接种物或凋落物物种身份无关。响应于另一种豆科植物处理过的土壤，根瘤形成受到局部抑制，并且对同种土壤有系统减少的趋势。凋落物还引起了系统响应，在根系未直接接触凋落物的部分产生了更细的根。
根系凋落物分布和土壤群落的空间异质性在根形态和根瘤形成方面产生了明显的局部和系统响应。这些响应会影响植物与共生体的相互作用和养分循环，应纳入植物共存模型中。
