State Key Laboratory of Nutrient Use and Management (SKL-NUM), College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, 100193, Beijing, People's Republic of China.
Kansas Biological Survey and Center for Ecological Research, University of Kansas, Lawrence, KS, 66045, USA.
Nat Commun. 2023 Dec 18;14(1):8417. doi: 10.1038/s41467-023-44253-4.
Productivity benefits from diversity can arise when compatible pathogen hosts are buffered by unrelated neighbors, diluting pathogen impacts. However, the generality of pathogen dilution has been controversial and rarely tested within biodiversity manipulations. Here, we test whether soil pathogen dilution generates diversity- productivity relationships using a field biodiversity-manipulation experiment, greenhouse assays, and feedback modeling. We find that the accumulation of specialist pathogens in monocultures decreases host plant yields and that pathogen dilution predicts plant productivity gains derived from diversity. Pathogen specialization predicts the strength of the negative feedback between plant species in greenhouse assays. These feedbacks significantly predict the overyielding measured in the field the following year. This relationship strengthens when accounting for the expected dilution of pathogens in mixtures. Using a feedback model, we corroborate that pathogen dilution drives overyielding. Combined empirical and theoretical evidence indicate that specialist pathogen dilution generates overyielding and suggests that the risk of losing productivity benefits from diversity may be highest where environmental change decouples plant-microbe interactions.
当相容的病原体宿主被无关的邻居缓冲时，生产力会从多样性中受益，从而稀释病原体的影响。然而，病原体稀释的普遍性一直存在争议，并且在生物多样性操纵中很少得到验证。在这里，我们使用野外生物多样性操纵实验、温室实验和反馈模型来测试土壤病原体稀释是否会产生多样性-生产力关系。我们发现，专性病原菌在单培养物中的积累会降低宿主植物的产量，而病原菌稀释则可以预测多样性带来的植物生产力的提高。病原菌的专化性预测了温室实验中植物物种之间负反馈的强度。这些反馈显著预测了次年田间的超额产量。当考虑到混合物中病原菌预期的稀释时，这种关系会增强。使用反馈模型，我们证实了病原菌稀释会导致超额产量。实证和理论证据表明，专性病原菌的稀释会产生超额产量，并表明在环境变化使植物-微生物相互作用脱钩的地方，失去多样性带来的生产力收益的风险可能最高。
