Melon powdery mildew is a devastating disease caused by Podosphaera xanthii. To identify and characterize mycoviruses of P. xanthii, total RNA of P. xanthi was extracted for constructing a library which was sequenced in a paired-end 2 × 75 bp mode of a NextSeq500 sequencer. Sequence analyses showed 87,607,242 clean reads, and 1076 unigenes were successfully matched with 151 mycovirus isolates within 71 mycovirus species. Among these isolates, 17 new isolates from four mycovirus species were identified. Their amino acid identity ranged from 32.8% to 100%. Phylogenetic relationships based on the RNA-dependent RNA polymerase protein of 37 isolates, including 20 retrieved from databases, showed a high divergence, which was confirmed by differences in genome structure and size. These results expand our understanding of the diversity of mycoviruses and will be useful for the development of potential biological control methods.

中文翻译：

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瓜类白粉病新型真菌病毒的鉴定与分析

甜瓜白粉病是一种由 Podosphaera xanthii 引起的毁灭性病害。为了鉴定和表征 P. xanthii 的真菌病毒，提取 P. xanthi 的总 RNA 以构建一个文库，该文库在 NextSeq500 测序仪的双端 2 × 75 bp 模式下进行测序。序列分析显示 87,607,242 个干净读取，1076 个 unigenes 与 71 个真菌病毒物种中的 151 个真菌病毒分离株成功匹配。在这些分离株中，鉴定出来自四种真菌病毒种类的 17 种新分离株。它们的氨基酸同一性在 32.8% 到 100% 之间。基于 37 个分离株（包括从数据库中检索到的 20 个）的 RNA 依赖性 RNA 聚合酶蛋白的系统发育关系显示出高度差异，这通过基因组结构和大小的差异得到证实。