A new fungal species constantly associated with hazelnut (Corylus avellana) fructification starting from its primordia is described. The fungus is associated with hazelnut fruit during all their developmental stages, being consistently more present in spring (March–June). A 4-year survey has been conducted, from young fruit formation to full kernel maturity including also the post-harvest phase, to collect fungi associated with damaged/discoloured kernels. A collection of 60 isolates of a new species has been obtained in this study, which is here described as Didymella corylicola sp. nov. Multi-locus phylogenies based on four genomic loci (nuITS and LSU rDNA, RPB2 and TUB2) in combination with morphological data confirmed the fungus to represent a new species of Didymella (Didymellaceae). The occurrence of D. corylicola sp. nov. might have an impact on the quality of hazelnut production by contributing to kernel defects.

中文翻译：

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Didymella corylicola sp。nov。，一种与意大利榛子果实开发相关的新真菌

描述了一种从原基开始就不断与榛子（Corylus avellana）果糖化相关的新真菌物种。真菌在所有发育阶段都与榛子果实相关，并在春季（3月至6月）持续存在。为了收集与受损/变色果仁相关的真菌，从幼果形成到完整的果仁成熟期（包括收获后阶段），已经进行了为期4年的调查。在这项研究中已收集到60个新物种的分离株，在此被称为Didymella corylicola sp.。十一月 基于四个基因组位点（nuITS和LSU rDNA，RPB2和TUB2）的多基因位系统发育）与形态学数据相结合，证实了该真菌代表了迪迪米拉（Didymellaceae）的一个新物种。D的出现。corylicola SP。十一月 可能通过导致仁缺陷而对榛子生产的质量产生影响。