The best of both worlds: a combined approach for analyzing microalgal diversity via metabarcoding and morphology-based methods

An increasing number of studies use next generation sequencing (NGS) to analyze complex communities, but is the method sensitive enough when it comes to identification and quantification of species? We compared NGS with morphology-based identification methods in an analysis of microalgal (periphyton) communities. We conducted a mesocosm experiment in which we allowed two benthic grazer species to feed upon benthic biofilms, which resulted in altered periphyton communities. Morphology-based identification and 454 (Roche) pyrosequencing of the V4 region in the small ribosomal unit (18S) rDNA gene were used to investigate the community change caused by grazing. Both the NGS-based data and the morphology-based method detected a marked shift in the biofilm composition, though the two methods varied strongly in their abilities to detect and quantify specific taxa, and neither method was able to detect all species in the biofilms. For quantitative analysis, we therefore recommend using both me...越来越多的研究采用下一代测序（next generation sequencing, NGS）技术分析复杂群落，但该方法在物种鉴定与定量分析方面是否具备足够灵敏度？我们以微藻（周丛生物，periphyton）群落为研究对象，将下一代测序与基于形态学的鉴定方法进行了对比。我们开展了一项中宇宙实验（mesocosm experiment），让两种底栖牧食生物以底栖生物膜为食，由此使周丛生物群落发生了改变。我们采用基于形态学的鉴定方法，以及针对小核糖体亚基（18S）rDNA基因V4区的454焦磷酸测序（Roche 454 Pyrosequencing）技术，来探究牧食作用引发的群落变化。基于NGS的测序数据与基于形态学的鉴定方法均检测到了生物膜群落组成的显著变化，但两种方法在特定分类群的检测与定量能力上差异显著，且均无法完全检出生物膜中的所有物种。因此针对定量分析，我们建议同时采用...