Arbuscular mycorrhizal fungi (AMF) play important key roles in the soil ecosystems as they link plants to the root-inaccessible part of soil. The aims of this study were to investigate which environmental factors influence the spatial and temporal structuring of AMF communities associated to Picconia azorica in two Azorean islands (Terceira and São Miguel islands), and investigate the seasonal variation in AMF communities between the two islands. Communities of AMF associated with P. azorica in native forest of two Azorean islands (Terceira and São Miguel) were characterised by spore morphology or molecular analysis. Forty-five AMF spore morphotypes were detected from the four fragments of P. azorica forest representing nine families of AMF. Acaulosporaceae (14) and Glomeraceae (9) were the most abundant families. AMF density and root colonisation varied significantly between islands and sampling sites. Root colonisation and spore density exhibited temporal patterns, which peaked in spring and were higher in Terceira than in São Miguel. The relative contribution of environmental factors showed that factors such as elevation, relative air humidity, soil pH, and soil available P, K, and Mg influenced AMF spore production and root colonisation. Different sporulation patterns exhibited by the members of the commonest families suggested different life strategies. Adaptation to a particular climatic and soil condition and host phenology may explain seasonal differences in sporulation patterns. Cohorts of AMF associated to P. azorica are shaped by regional processes including environmental filters such as soil properties and natural disturbance.

中文翻译：

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环境因素驱动亚速尔群岛原生森林中特有木本植物Picconiaazorica的丛枝菌根真菌群落

丛枝菌根真菌（AMF）在土壤生态系统中起着重要的关键作用，因为它们将植物与土壤的根部难以接近的部分联系起来。这项研究的目的是调查哪些环境因素影响与两个亚速尔群岛（特尔塞拉岛和圣米格尔岛）的Azorica Picconia azorica有关的AMF群落的时空结构，并研究两个岛屿之间的AMF群落的季节性变化。通过孢子形态或分子分析对两个亚速尔群岛（Terceira和SãoMiguel）原生林中与P. azorica有关的AMF群落进行了表征。从代表九个AMF家族的P. azorica森林的四个片段中检测到四十五种AMF孢子形态。au科（14）和科（9）是最丰富的科。在岛屿和采样点之间，AMF密度和根定植显着不同。根部定植和孢子密度表现出时间模式，该模式在春季达到顶峰，在Terceira高于圣米格尔。环境因素的相对影响表明，海拔，相对空气湿度，土壤pH值以及土壤有效磷，钾和镁等因素会影响AMF孢子的产生和根部定植。最普通家庭成员表现出的孢子形成方式不同，表明了不同的生活策略。适应特定的气候和土壤条件以及宿主物候可能解释了孢子形成方式的季节性差异。与P. azorica相关的AMF队列由包括环境过滤器（例如土壤特性和自然干扰）在内的区域性过程形成。