Testing PCR primers to accurately monitor pollinator communities from plant-derived eDNA

Abstract Plant derived environmental DNA (eDNA) has revolutionized our ability to study terrestrial arthropod communities. However, bee pollinators are still severely unrepresented in eDNA analyses. Here, we designed several PCR primers to enrich insects from plant-derived eDNA. We especially focussed on the utility of the primers to reconstruct pollinator communities, particularly on wild bees. We tested our primers using mock communities of different bee species as well as field collected flower eDNA samples. We found that all our primers are highly promising to enrich insect eDNA from plant material. All primers also provide highly reliable in recovering bee DNA. The primers recovered all bee species from the mock communities and also approximated their relative abundance. Moreover, we found highly diverse insect communities from our field collected samples, including diverse bee pollinators. Our study highlights the great promise of eDNA metabarcoding for the monitoring of plant associated insects, especially bee pollinators. The presented primer sets will greatly contribute to the status and interaction diversity of insect pollinator communities.摘要 植物源环境DNA（environmental DNA，eDNA）彻底革新了我们研究陆生节肢动物群落的能力。然而，传粉蜜蜂在eDNA分析中的代表性仍严重不足。 本研究设计了多款聚合酶链式反应（Polymerase Chain Reaction，PCR）引物，用于从植物源eDNA中富集昆虫核酸。本研究尤其聚焦于这些引物在重构传粉者群落（尤其是野生蜜蜂）方面的应用效能。研究团队使用不同蜜蜂物种的模拟群落以及野外采集的花卉eDNA样本对引物进行了测试。 结果显示，所有引物均具备从植物样本中富集昆虫eDNA的良好潜力，且在捕获蜜蜂DNA方面表现出极高的可靠性。引物可从模拟群落中检出全部蜜蜂物种，还能准确估算其相对丰度。此外，对野外采集样本的分析结果显示昆虫群落多样性极高，涵盖多种传粉蜜蜂。 本研究凸显了eDNA元条形码技术（metabarcoding）在监测植物关联昆虫（尤其是传粉蜜蜂）方面的巨大应用前景。本次报道的引物套装将极大助力昆虫传粉者群落的物种现状与互作多样性研究。