The use of environmental DNA (eDNA) surveys to monitor terrestrial species has been relatively limited, with successful implementations still confined to sampling DNA from natural or artificial water bodies and soil. Sampling water for eDNA depends on proximity to or availability of water, whereas eDNA from soil is limited in its spatial scale due to the large quantities necessary for processing and difficulty in doing so. These challenges limit the widespread use of eDNA in several systems, such as surveying forests for invasive insects. We developed two new eDNA aggregation approaches that overcome the challenges of above-ground terrestrial sampling and eliminate the dependency on creating or utilizing pre-existing water bodies to conduct eDNA sampling. The first, "spray aggregation," uses spray action to remove eDNA from surface substrates and was developed for shrubs and other understorey vegetation, while the second, "tree rolling," uses physical transfer via a roller to remove eDNA from the surface of tree trunks and large branches. We tested these approaches by surveying for spotted lanternfly, Lycorma delicatula, a recent invasive pest of northeastern USA that is considered a significant ecological and economic threat to forests and agriculture. We found that our terrestrial eDNA surveys matched visual surveys, but also detected L. delicatula presence ahead of visual surveys, indicating increased sensitivity of terrestrial eDNA surveys over currently used methodology. The terrestrial eDNA approaches we describe can be adapted for use in surveying a variety of forest insects and represent a novel strategy for surveying terrestrial biodiversity.

中文翻译：

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将eDNA调查移到土地上：主动eDNA聚集以检测入侵森林昆虫的策略。

使用环境DNA（eDNA）调查来监测陆生物种相对有限，成功实施仍仅限于从天然或人工水体和土壤中采样DNA。为eDNA采样水取决于水的接近性或可用性，而土壤中eDNA的空间规模有限，这是因为处理所需的大量水量以及这样做的难度。这些挑战限制了eDNA在几种系统中的广泛使用，例如调查森林中的入侵昆虫。我们开发了两种新的eDNA聚合方法，这些方法克服了地面上地面采样的挑战，并消除了对创建或利用现有水体进行eDNA采样的依赖性。第一个是“喷雾聚合” 它利用喷雾作用从表层基质上去除eDNA，并被开发用于灌木和其他地下植被，而第二种“树状滚动”则通过滚筒进行物理转移，从而从树干和大树枝表面去除eDNA。我们通过调查斑纹的天蛾Lycorma delicatula（一种美国东北部最近的入侵害虫）被测试了这些方法，该害虫被视为对森林和农业的重大生态和经济威胁。我们发现，我们的陆地eDNA调查与视觉调查相匹配，但是在视觉调查之前也检测到了纤毛乳杆菌的存在，这表明陆地eDNA调查相对于当前使用的方法更加敏感。