The meadow spittlebug, Philaenus spumarius L. (Hemiptera: Aphrophoridae), is the main vector of the phytopathogenic bacterium Xylella fastidiosa in Europe, where the ST53 strain induces the olive quick decline syndrome, causing severe economic damage in southern Italy. The wide range of plant species infected by X. fastidiosa, and the wide host range of P. spumarius suggest that a large number of wild and cultivated plants may become infected by the pathogen following unintentional introduction events. Therefore, it is necessary to detail the host plant preference of the vector, in order to include preferred plants in the field, in pathogen‐targeted diagnostic efforts. This would allow the identification of main sources of X. fastidiosa acquisition by P. spumarius; such plant species represent an important target for rational disease management. Here, we investigated the host plants of P. spumarius in north‐western Italy, a region where X. fastidiosa is still not present but is regarded as a primary threat. We designed a new molecular diagnostic tool targeting chloroplast DNA, to characterize the gut content of single P. spumarius adults. The newly set up, nested PCR/sequencing‐based identification protocol was proven to be useful for retrieving sequences from the last two different host plants used by P. spumarius, even if limited persistence of intact chloroplast DNA was reported in the spittlebug gut. We propose this protocol as a new tool for supporting research on xylem feeder biology that could be particularly useful for highly polyphagous species such as P. spumarius. Furthermore, the method could help monitor X. fastidiosa invasion, and contribute to the study of vector ecology and pathogen epidemiology.

中文翻译：

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通过肠道含量分析鉴定多面木质部饲养者 Philaenus spumarius 中的寄主植物

草甸飞虱（Philaenus spumarius L.）（半翅目：Aphrophoridae）是欧洲植物病原菌 Xylella fastidiosa 的主要载体，ST53 菌株诱导橄榄快速衰退综合征，在意大利南部造成严重的经济损失。被 X. fastidiosa 感染的植物种类范围广泛，而 P. spumarius 的寄主范围广泛，这表明大量野生和栽培植物可能在无意引入事件后被病原体感染。因此，有必要详细说明载体对宿主植物的偏好，以便在病原体靶向诊断工作中包括田间首选植物。这将允许鉴定由 P. spumarius 获得的 X. fastidiosa 的主要来源；此类植物物种代表了合理疾病管理的重要目标。在这里，我们调查了意大利西北部 P. spumarius 的寄主植物，该地区的 X. fastidiosa 仍然不存在，但被视为主要威胁。我们设计了一种针对叶绿体 DNA 的新分子诊断工具，以表征单个 P. spumarius 成虫的肠道含量。新建立的、基于嵌套 PCR/测序的识别协议被证明可用于从 P. spumarius 使用的最后两种不同宿主植物中检索序列，即使在 spittlebug 肠道中报告完整叶绿体 DNA 的持久性有限。我们建议将此协议作为支持木质部饲养者生物学研究的新工具，该工具可能对高度多食性物种（如 P. spumarius）特别有用。此外，该方法可以帮助监测 X. fastidiosa 入侵，