Data_Sheet_2_Characterization of the Wood Mycobiome of Vitis vinifera in a Vineyard Affected by Esca. Spatial Distribution of Fungal Communities and Their Putative Relation With Leaf Symptoms.xls

Esca is a disease complex belonging to the grapevine trunk diseases cluster. It comprises five syndromes, three main fungal pathogenic agents and several symptoms, both internal (i.e., affecting woody tissue) and external (e.g., affecting leaves and bunches). The etiology and epidemiology of this disease complex remain, in part, unclear. Some of the points that are still under discussion concern the sudden rise in disease incidence, the simultaneous presence of multiple wood pathogens in affected grapevines, the causal agents and the discontinuity in time of leaf symptoms manifestation. The standard approach to the study of esca has been mostly through culture-dependent studies, yet, leaving many questions unanswered. In this study, we used Illumina® next-generation amplicon sequencing to investigate the mycobiome of grapevines wood in a vineyard with history of esca. We characterized the wood mycobiome composition, investigated the spatial dynamics of the fungal communities in different areas of the stem and in canes, and assessed the putative link between mycobiome and leaf symptoms. An unprecedented diversity of fungi is presented (289 taxa), including five genera reported for the first time in association with grapevines wood (Debaryomyces, Trematosphaeria, Biatriospora, Lopadostoma, and Malassezia) and numerous hitherto unreported species. Esca-associated fungi Phaeomoniella chlamydospora and Fomitiporia sp. dominate the fungal community, and numerous other fungi associated with wood syndromes are also encountered (e.g., Eutypa spp., Inonotus hispidus). The spatial analysis revealed differences in diversity, evenness and taxa abundances, the unique presence of certain fungi in specific areas of the plants, and tissue specificity. Lastly, the mycobiome composition of the woody tissue in proximity to leaves manifesting ‘tiger stripes’ symptoms of esca, as well as in leaf-symptomatic canes, was highly similar to that of plants not exhibiting any leaf symptomatology. This observation supports the current understanding that leaf symptoms are not directly linked with the fungal communities in the wood. This work builds to the understanding of the microbial ecology of the grapevines wood, offering insights and a critical view on the current knowledge of the etiology of esca.

埃斯卡病（Esca）是一类归属于葡萄树干病害集群的病害复合体，包含5种综合征、3种主要真菌病原菌以及多种内部（即侵染木质组织）和外部（例如侵染叶片与果穗）症状。该病害复合体的病因学与流行病学仍有部分尚未明确。当前仍存在争议的问题包括：病害发生率的突发升高、受侵染葡萄树内多种木质部病原菌的同时存在、病原菌的确定，以及叶片症状表现的时间间断性。以往针对埃斯卡病的研究多采用依赖培养的研究方法，这使得诸多问题仍未得到解答。本研究利用Illumina®新一代扩增子测序技术，对某具埃斯卡病侵染历史的葡萄园中的葡萄树木质部真菌组（mycobiome）进行了分析。我们对木质部真菌组的组成进行了表征，探究了茎干不同区域及新梢中真菌群落的空间动态，并评估了真菌组与叶片症状之间的潜在关联。本次研究揭示了前所未有的真菌多样性（共289个分类单元），其中包含5个首次被报道与葡萄树木质部相关联的真菌属（德巴利酵母属Debaryomyces、孔壳属Trematosphaeria、双囊孢属Biatriospora、盾壳属Lopadostoma及马拉色菌属Malassezia），以及诸多迄今尚未被报道的物种。与埃斯卡病相关的真菌——厚垣孢平座霉（Phaeomoniella chlamydospora）和拟层孔菌属（Fomitiporia sp.）为群落中的优势类群，同时还检测到诸多其他与木质部综合征相关的真菌（例如日规壳属Eutypa spp.及多毛纤孔菌Inonotus hispidus）。空间分析结果显示，真菌的多样性、均匀度及分类单元丰度存在差异，特定真菌仅存在于植株的特定区域，且表现出组织特异性。最后，对表现出埃斯卡病"虎斑叶"症状的叶片附近木质组织，以及表现叶片症状的新梢所进行的真菌组分析结果，与未表现任何叶片症状的植株木质组织真菌组高度相似。该观测结果支持当前的认知：叶片症状与木质部内的真菌群落并无直接关联。本研究增进了我们对葡萄树木质部微生物生态学的理解，为埃斯卡病病因学的现有认知提供了新见解，并对其提出了批判性审视。