Mursinoff Sini, Tack Ayco J M
Department of Biosciences, University of Helsinki, PO Box 65 (Viikinkaari 1), FI-00014, Helsinki, Finland.
Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91, Stockholm, Sweden.
New Phytol. 2017 Apr;214(2):644-654. doi: 10.1111/nph.14402. Epub 2017 Jan 2.
Theory suggests that below-ground spatial heterogeneity may mediate host-parasite evolutionary dynamics and patterns of local adaptation, but this has rarely been tested in natural systems. Here, we test experimentally for the impact of spatial variation in the abiotic and biotic soil environment on the evolutionary outcome of the interaction between the host plant Plantago lanceolata and its specialist foliar pathogen Podosphaera plantaginis. Plants showed no adaptation to the local soil environment in the absence of natural enemies. However, quantitative, but not qualitative, plant resistance against local pathogens was higher when plants were grown in their local field soil than when they were grown in nonlocal field soil. This pattern was robust when extending the spatial scale beyond a single region, but disappeared with soil sterilization, indicating that soil biota mediated plant adaptation. We conclude that below-ground biotic heterogeneity mediates above-ground patterns of plant adaptation, resulting in increased plant resistance when plants are grown in their local soil environment. From an applied perspective, our findings emphasize the importance of using locally selected seeds in restoration ecology and low-input agriculture.
理论表明，地下空间异质性可能会调节宿主 - 寄生虫的进化动态和局部适应模式，但这在自然系统中很少得到验证。在此，我们通过实验测试了非生物和生物土壤环境中的空间变化对宿主植物披针叶车前（Plantago lanceolata）与其专性叶部病原体车前白粉菌（Podosphaera plantaginis）之间相互作用的进化结果的影响。在没有天敌的情况下，植物对当地土壤环境没有适应性。然而，当植物在其当地田间土壤中生长时，对当地病原体的定量抗性（而非定性抗性）高于在非当地田间土壤中生长时。当将空间尺度扩展到单个区域之外时，这种模式依然稳健，但在土壤灭菌后消失了，这表明土壤生物群落介导了植物的适应性。我们得出结论，地下生物异质性介导了地上植物的适应模式，当植物在其当地土壤环境中生长时会增强植物抗性。从应用角度来看，我们的研究结果强调了在恢复生态学和低投入农业中使用本地选择种子的重要性。
