Riolo Mario, Aloi Francesco, Conti Taguali Sebastiano, Pane Antonella, Franco Massimo, Cacciola Santa Olga
Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy.
Department of Agricultural Science, Mediterranean University of Reggio Calabria, 89122 Reggio Calabria, Italy.
J Fungi (Basel). 2022 Sep 18;8(9):973. doi: 10.3390/jof8090973.
The objective of this study was to investigate the role of the oomycete in the decline affecting European beech () in the Nebrodi Regional Park (Sicily, southern Italy). In a survey of a beech forest stand in the heart of the park, was the sole species recovered from the rhizosphere soil and fine roots of trees. Both A1 and A2 mating type isolates were found. Direct isolation from the stem bark of trees showing severe decline symptoms and bleeding stem cankers yielded exclusively , usually considered as an opportunistic pathogen. The mean inoculum density of in the rhizosphere soil, as determined using the soil dilution plating method and expressed in terms of colony forming units (cfus) per gm of soil, the isolation frequency using leaf baiting, and the percentage of infected fibrous roots from 20 randomly selected beech trees with severe decline symptoms (50 to 100 foliage transparency classes) were 31.7 cfus, 80%, and 48.6%, respectively. These were significantly higher than the corresponding mean values of 20 asymptomatic or slightly declining trees, suggesting is a major factor responsible for the decline in the surveyed stand.
本研究的目的是调查卵菌纲生物在影响内布罗迪地区公园（意大利南部西西里岛）欧洲山毛榉（）衰退过程中的作用。在对公园中心一片山毛榉林分的调查中，是从树木根际土壤和细根中分离出的唯一物种。发现了A1和A2交配型分离株。从表现出严重衰退症状和茎干溃疡出血的树木茎干树皮直接分离，仅得到，通常被认为是一种机会性病原菌。使用土壤稀释平板法测定并以每克土壤的菌落形成单位（cfus）表示的根际土壤中平均接种密度、使用叶片诱饵法的分离频率以及从20棵随机选择的具有严重衰退症状（50至100个叶片透明度等级）的山毛榉树中感染的须根百分比分别为31.7 cfus、80%和48.6%。这些值显著高于20棵无症状或轻度衰退树木的相应平均值，表明是导致被调查林分衰退的主要因素。
