Caballol Maria, Redondo Miguel Ángel, Catalán Núria, Corcobado Tamara, Jung Thomas, Marçais Benoît, Milenković Ivan, Nemesio-Gorriz Miguel, Stenlid Jan, Oliva Jonàs
Department of Agricultural and Forest Sciences and Engineering, University of Lleida, Lleida 25198, Spain.
Joint Research Unit CTFC - AGROTECNIO-CERCA, Lleida 25198, Spain.
ISME J. 2024 Jan 8;18(1). doi: 10.1093/ismejo/wrae010.
Climate shapes the distribution of plant-associated microbes such as mycorrhizal and endophytic fungi. However, the role of climate in plant pathogen community assembly is less understood. Here, we explored the role of climate in the assembly of Phytophthora communities at >250 sites along a latitudinal gradient from Spain to northern Sweden and an altitudinal gradient from the Spanish Pyrenees to lowland areas. Communities were detected by ITS sequencing of river filtrates. Mediation analysis supported the role of climate in the biogeography of Phytophthora and ruled out other environmental factors such as geography or tree diversity. Comparisons of functional and species diversity showed that environmental filtering dominated over competitive exclusion in Europe. Temperature and precipitation acted as environmental filters at different extremes of the gradients. In northern regions, winter temperatures acted as an environmental filter on Phytophthora community assembly, selecting species adapted to survive low minimum temperatures. In southern latitudes, a hot dry climate was the main environmental filter, resulting in communities dominated by drought-tolerant Phytophthora species with thick oospore walls, a high optimum temperature for growth, and a high maximum temperature limit for growth. By taking a community ecology approach, we show that the establishment of Phytophthora plant pathogens in Europe is mainly restricted by cold temperatures.
气候塑造了与植物相关的微生物（如菌根真菌和内生真菌）的分布。然而，气候在植物病原体群落组装中的作用却鲜为人知。在此，我们沿着从西班牙到瑞典北部的纬度梯度以及从西班牙比利牛斯山脉到低地地区的海拔梯度，在250多个地点探索了气候在疫霉群落组装中的作用。通过对河流滤液进行ITS测序来检测群落。中介分析支持了气候在疫霉生物地理学中的作用，并排除了其他环境因素，如地理或树木多样性。功能多样性和物种多样性的比较表明，在欧洲，环境过滤作用超过了竞争排斥作用。温度和降水在梯度的不同极端情况下充当环境过滤器。在北部地区，冬季温度对疫霉群落组装起到环境过滤作用，选择适应在低温下生存的物种。在南部纬度地区，炎热干燥的气候是主要的环境过滤器，导致群落以具有厚卵孢子壁、生长最适温度高和生长最高温度限制高的耐旱疫霉物种为主。通过采用群落生态学方法，我们表明欧洲疫霉植物病原体的定殖主要受低温限制。
