Species of Eucalyptus are widely planted as exotics in the tropics and Southern Hemisphere and to some extent in southern Europe, for timber and fibre production. Species of Mycosphaerella are commonly associated with leaves and twigs of Eucalyptus and can result in defoliation, dieback, and even tree death. In the present study, numerous isolates of Mycosphaerella species were collected from leaf litter, living leaves exhibiting leaf spot symptoms or severe Mycosphaerella leaf blotch symptoms. Isolates were compared based on DNA sequence data for the internal transcribed spacer region (ITS1 & ITS2) and the 5.8S gene. These data, together with characteristics of the fungal growth on three different media, morphology of the anamorph and teleomorph structures as well as ascospore germination patterns were used to describe 21 new species.

中文翻译：

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Mycosphaerella spp. 的系统发育重新评估。以及它们在桉树上发生的变形。二、

桉树物种作为外来物种在热带和南半球以及在一定程度上在南欧被广泛种植，用于木材和纤维生产。Mycosphaerella 物种通常与桉树的叶子和树枝有关，可导致落叶、枯死，甚至树木死亡。在本研究中，从枯枝落叶、表现出叶斑症状或严重的Mycosphaerella 叶斑病症状的活叶中收集了大量Mycosphaerella 物种的分离物。根据内部转录间隔区（ITS1 和 ITS2）和 5.8S 基因的 DNA 序列数据比较分离物。这些数据，连同真菌在三种不同培养基上的生长特征、无形和有形结构的形态以及子囊孢子萌发模式被用来描述 21 个新物种。