Data from: Determining plant – leaf miner – parasitoid interactions: a DNA barcoding approach

A major challenge in network ecology is to describe the full-range of species interactions in a community to create highly-resolved food-webs. We developed a molecular approach based on DNA full barcoding and mini-barcoding to describe difficult to observe plant – leaf miner – parasitoid interactions, consisting of animals commonly regarded as agricultural pests and their natural enemies. We tested the ability of universal primers to amplify the remaining DNA inside leaf miner mines after the emergence of the insect. We compared the results of a) morphological identification of adult specimens; b) identification based on the shape of the mines; c) the COI Mini-barcode (130 bp) and d) the COI full barcode (658 bp) fragments to accurately identify the leaf-miner species. We used the molecular approach to build and analyse a tri-partite ecological network of plant – leaf miner – parasitoid interactions. We were able to detect the DNA of leaf-mining insects within their feeding mines on a range of host plants using mini-barcoding primers: 6% for the leaves collected empty and 33% success after we observed the emergence of the leaf miner. We suggest that the low amplification success of leaf mines collected empty was mainly due to the time since the adult emerged and discuss methodological improvements. Nevertheless our approach provided new species-interaction data for the ecological network. We found that the 130 bp fragment is variable enough to identify all the species included in this study. Both COI fragments reveal that some leaf miner species could be composed of cryptic species. The network built using the molecular approach was more accurate in describing tri-partite interactions compared with traditional approaches based on morphological criteria.

网络生态学（network ecology）的一项重大挑战，在于完整刻画群落内的全部物种互作关系，以构建高分辨率食物网。我们开发了一种基于DNA全条形码（DNA full barcoding）与微型条形码（mini-barcoding）的分子学方法，用以解析难以直接观测的植物-潜叶虫-寄生蜂互作体系——该体系涵盖通常被视为农业害虫的昆虫及其天敌。我们验证了通用引物对昆虫羽化后潜叶虫道内残留DNA的扩增能力，并对比了四种鉴定方案以准确鉴定潜叶虫物种：a) 成虫标本的形态学鉴定；b) 基于潜叶虫道形态的鉴定；c) COI微型条形码（130 bp）；d) COI全条形码（658 bp）。我们利用该分子方法构建并分析了植物-潜叶虫-寄生蜂三方互作的生态网络。通过微型条形码引物，我们在多种寄主植物的潜叶虫道内成功检测到潜叶昆虫的DNA：采集时已无虫的叶片样本扩增成功率为6%，在观测到潜叶虫羽化的样本中成功率达33%。我们推测，空叶虫道样本较低的扩增成功率主要与成虫羽化后的时间间隔相关，并对方法学改进方向展开了讨论。尽管如此，本方法仍为生态网络研究提供了全新的物种互作数据。本研究发现，130 bp的COI微型条形码片段具有足够的序列变异性，可准确鉴定本研究涵盖的所有物种；两种COI条形码片段均显示，部分潜叶虫物种可能由隐存种构成。相较于基于形态学标准的传统研究方法，采用分子方法构建的生态网络，对三方互作关系的描述更为精准。