Agriculture Victoria, AgriBio Centre, Bundoora, Victoria, Australia.
Agriculture Victoria, Grains Innovation Park, Horsham, Victoria, Australia.
PLoS One. 2024 Oct 10;19(10):e0311938. doi: 10.1371/journal.pone.0311938. eCollection 2024.
Spittlebugs and froghoppers (Hemiptera: Cercopoidea) are insects feeding on xylem, which potentially can cause significant economic damage worldwide by transmitting plant pathogenic bacteria such as Xylella fastidiosa. Australia and New Zealand are currently free from X. fastidiosa, but they are home to at least 45 native spittlebug species. Among these, the Australian natives Bathyllus albicinctus (Erichson, 1842) and Philagra parva (Donovan, 1805) are particularly widespread and can be found across southern and eastern Australia, with B. albicinctus also in New Zealand. The potential that both species might be capable of vectoring Xylella fastidiosa poses a substantial biosecurity risk if the bacterium were to invade these regions. In this study, we examined 87 spittlebug nymphs collected across 12 different host plant species, in five locations in Victoria, Australia. Our objective was to explore the factors influencing bacterial communities within and between these widespread spittlebug species, considering geographic location, insect phylogenetics, and host plant associations. We employed COI barcoding to assess insect genetic variation and 16S high throughput sequencing (HTS) metabarcoding to analyse bacterial microbiome diversity across various host plants. Our findings revealed minimal genetic divergence among spittlebug individuals in the same species, highlighting conspecificity despite conspicuous morphological divergences. On the other hand, we recorded significant variation in bacterial communities harboured by Bathyllus albicinctus nymphs feeding on different plants, even when these were collected within close proximity to each other. Therefore, host plant association appeared to shape the bacterial communities of spittlebugs more than insect genetic divergence or geographical location. These diverse bacterial communities could potentially facilitate transmission of plant pathogenic bacteria, underscoring the risk of widespread transmission among numerous plant hosts through insect-plant interactions. This study emphasizes the critical need to understand these complex interactions, particularly in the context of biosecurity.
沫蝉和跳甲（半翅目：沫蝉科）以木质部为食的昆虫，它们通过传播诸如韧皮部难养菌（Xylella fastidiosa）等植物病原菌，在全球范围内可能造成重大的经济损失。澳大利亚和新西兰目前没有韧皮部难养菌，但它们至少有 45 种本土沫蝉物种。其中，澳大利亚本土的巴氏沫蝉（Bathyllus albicinctus）（Erichson，1842）和小沫蝉（Philagra parva）（Donovan，1805）分布特别广泛，在澳大利亚南部和东部各地都能发现，巴氏沫蝉在新西兰也有分布。如果这些地区遭到入侵，这两个物种都有可能传播韧皮部难养菌，这将构成重大的生物安全风险。在这项研究中，我们检查了在澳大利亚维多利亚州五个地点的 12 种不同寄主植物上收集的 87 只沫蝉若虫。我们的目的是探讨影响这些广泛分布的沫蝉种内和种间细菌群落的因素，考虑地理位置、昆虫系统发育和寄主植物的联系。我们采用 COI 条形码来评估昆虫的遗传变异，16S 高通量测序（HTS）宏条形码分析不同寄主植物上的细菌微生物多样性。我们的研究结果表明，同一物种的沫蝉个体之间遗传分化极小，尽管形态上存在明显的差异，但仍具有同属特征。另一方面，我们记录了在不同植物上取食的巴氏沫蝉若虫所携带的细菌群落存在显著差异，即使这些若虫是在彼此非常接近的地方收集的。因此，寄主植物的联系似乎比昆虫的遗传分化或地理位置更能塑造沫蝉的细菌群落。这些多样化的细菌群落可能会促进植物病原菌的传播，突出了通过昆虫-植物相互作用在众多植物寄主中广泛传播的风险。这项研究强调了在生物安全背景下，了解这些复杂相互作用的迫切需要。
