Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, PR China.
State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, PR China.
Ann Bot. 2022 Sep 26;130(4):525-534. doi: 10.1093/aob/mcac093.
Plant disease can dramatically affect population dynamics, community composition and ecosystem functions. However, most empirical studies focus on diseases at a certain time point and largely ignore their temporal stability, which directly affects our ability to predict when and where disease outbreaks will occur.
Using a removal experiment that manipulates plant diversity (i.e. a plant biodiversity and ecosystem function experiment) and a fertilization experiment in a Tibetan alpine meadow, we investigated how different plant biodiversity indices and nitrogen fertilization affect the temporal stability of foliar fungal diseases (measured as the mean value of community pathogen load divided by its standard deviation) over seven consecutive years.
We found that the temporal stability of foliar fungal diseases increased with plant diversity indices in the plant biodiversity and ecosystem function experiment. Meanwhile, we observed a weakly positive relationship between host diversity and temporal stability in the fertilization experiment. However, the nitrogen treatment did not affect temporal stability, given that fertilization increased both the mean and standard deviation of pathogen load by roughly the same magnitude.
We conclude that host diversity regulates the temporal stability of pathogen load, but we note that this effect may be attenuated under rapid biodiversity loss in the Anthropocene.
植物病害会显著影响种群动态、群落组成和生态系统功能。然而，大多数实证研究都集中在某一时间点的疾病上，而在很大程度上忽略了其时间稳定性，这直接影响了我们预测疾病何时何地爆发的能力。
本研究利用去除实验（即植物生物多样性和生态系统功能实验）和西藏高寒草甸的施肥实验，研究了不同的植物生物多样性指数和氮素施肥如何影响叶片真菌病害的时间稳定性（以群落病原体负荷的平均值除以其标准差来衡量），共进行了七年。
我们发现，在植物生物多样性和生态系统功能实验中，叶片真菌病害的时间稳定性随着植物多样性指数的增加而增加。同时，我们在施肥实验中观察到宿主多样性与时间稳定性之间存在弱正相关关系。然而，氮处理并没有影响时间稳定性，因为施肥大致以相同的幅度增加了病原体负荷的平均值和标准差。
我们得出结论，宿主多样性调节了病原体负荷的时间稳定性，但我们注意到，在人类世快速生物多样性丧失的情况下，这种影响可能会减弱。
