School of Molecular and Life Sciences, Curtin University, Bentley, Australia.
EcoHealth Network, Brookline, MA, USA.
Sci Rep. 2022 Mar 21;12(1):4778. doi: 10.1038/s41598-022-08580-8.
Prey spectra (the number and composition of captured arthropods) represent a crucial aspect of carnivorous plant ecology, yet remain poorly studied. Traditional morphology-based approaches for prey identification are time-intensive, require specialists with considerable knowledge of arthropod taxonomy, and are hampered by high numbers of unidentifiable (i.e., heavily digested) prey items. We examined prey spectra of three species of closely-related annual Drosera (Droseraceae, sundews) from tropical northern Australia using a novel DNA metabarcoding approach with in-situ macro photography as a plausibility control and to facilitate prey quantity estimations. This new method facilitated accurate analyses of carnivorous plant prey spectra (even of heavily digested prey lacking characteristic morphological features) at a taxonomic resolution and level of completeness far exceeding morphology-based methods and approaching the 100% mark at arthropod order level. Although the three studied species exhibited significant differences in detected prey spectra, little prey specialisation was observed and habitat or plant population density variations were likely the main drivers of prey spectra dissimilarity.
猎物谱（被捕食的节肢动物的数量和组成）是肉食性植物生态学的一个重要方面，但研究甚少。传统的基于形态的猎物鉴定方法耗时耗力，需要对节肢动物分类学有相当了解的专家，并且由于大量无法识别的（即，严重消化的）猎物而受到阻碍。我们使用一种新颖的 DNA metabarcoding 方法，结合现场宏观摄影作为合理性控制，并促进猎物数量估计，研究了来自澳大利亚热带北部的三种密切相关的一年生茅膏菜（茅膏菜科，茅膏菜）的猎物谱。这种新方法能够以分类分辨率和完整性水平非常高的方式准确分析肉食性植物的猎物谱（即使是严重消化的猎物缺乏特征形态特征），远远超过基于形态的方法，并在节肢动物目水平上接近 100%。尽管研究的三种物种在检测到的猎物谱上表现出显著差异，但观察到的猎物专业化很少，栖息地或植物种群密度的变化可能是猎物谱差异的主要驱动因素。
