Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
Yiyang Forestry Bureau, Yiyang, China.
Mol Ecol Resour. 2023 Aug;23(6):1389-1402. doi: 10.1111/1755-0998.13797. Epub 2023 Apr 23.
DNA barcoding is a well-established tool for rapid species identification and biodiversity monitoring. A reliable and traceable DNA barcode reference library with extensive coverage is necessary but unavailable for many geographical regions. The arid region in northwestern China, a vast area of about 2.5 million km , is ecologically fragile and often overlooked in biodiversity studies. In particular, DNA barcode data from the arid region in China are lacking. We develop and evaluate the efficacy of an extensive DNA barcode library for native flowering plants in the arid region of northwestern China. Plant specimens were collected, identified and vouchered for this purpose. The database utilized four DNA barcode markers, namely rbcL, matK, ITS and ITS2, for 1816 accessions (representing 890 species from 385 genera and 72 families), and consisted of 5196 barcode sequences. Individual barcodes varied in resolution rates: species- and genus-level rates for rbcL, matK, ITS and ITS2 were 79.9%-51.1%/76.1%, 79.9%-67.2%/88.9%, 85.0%-72.0%/88.2% and 81.0%-67.4%/84.9%, respectively. The three-barcode combination of rbcL + matK + ITS (RMI) revealed a higher species- and genus-level resolution (75.5%/92.1%, respectively). A total of 110 plastomes were newly generated as super-barcodes to increase species resolution for seven species-rich genera, namely Astragalus, Caragana, Lactuca, Lappula, Lepidium, Silene and Zygophyllum. Plastomes revealed higher species resolution compared to standard DNA barcodes and their combination. We suggest future databases include super-barcodes, especially for species-rich and complex genera. The plant DNA barcode library in the current study provides a valuable resource for future biological investigations in the arid regions of China.
DNA 条形码是一种快速物种鉴定和生物多样性监测的成熟工具。需要建立一个可靠且可追踪的、广泛涵盖的 DNA 条形码参考文库，但对于许多地理区域来说，这个文库仍然是缺失的。中国西北部干旱地区是一个约 250 万平方公里的广阔区域，生态脆弱，在生物多样性研究中经常被忽视。特别是，中国干旱地区的 DNA 条形码数据非常缺乏。我们为中国西北部干旱地区的本地开花植物开发并评估了一个广泛的 DNA 条形码文库的功效。为此目的收集、鉴定和凭证保存了植物标本。该数据库利用了四个 DNA 条形码标记，即 rbcL、matK、ITS 和 ITS2，涵盖了 1816 个样本（代表 72 个科 385 属 890 种），共包含 5196 条条形码序列。个体条形码的分辨率各不相同：rbcL、matK、ITS 和 ITS2 的种和属分辨率分别为 79.9%-51.1%/76.1%、79.9%-67.2%/88.9%、85.0%-72.0%/88.2%和 81.0%-67.4%/84.9%。rbcL+matK+ITS（RMI）的三标记组合显示出更高的种和属分辨率（分别为 75.5%/92.1%）。为了提高七个物种丰富属（即黄芪属、锦鸡儿属、莴苣属、鸦葱属、荠属、委陵菜属和蒺藜属）的物种分辨率，共生成了 110 个新的质体条形码作为超级条形码。质体条形码比标准 DNA 条形码及其组合具有更高的物种分辨率。我们建议未来的数据库包括超级条形码，特别是对于物种丰富和复杂的属。本研究中的植物 DNA 条形码文库为中国干旱地区未来的生物研究提供了有价值的资源。
