摘要
iFlora是结合传统分类学与DNA测序和信息技术,通过系列关键技术进行集成,构建便捷、准确识别物种和掌握相关数字化信息的新一代智能植物志。iFlora研发中首要和迫切的任务之一就是寻找适合于大多数植物和经济蘑菇的标准DNA条形码序列。为筛选适合大型经济蘑菇的DNA条形码,本研究以云南食用牛肝菌为例,选取野生食用菌市场上常见的、被当地人认为的4"种"牛肝菌为研究对象,利用核糖体大亚基(nrLSU)、翻译延长因子1-α(tef1-α)、RNA聚合酶II大亚基(rpb1)和RNA聚合酶II的第二个大亚基(rpb2)四个DNA序列,使用真核生物通用引物进行扩增、测序和测试。研究发现这4"种"样品实际上代表了12个独立的物种,进一步研究表明4个候选片段的扩增和测序成功率均为100%,且不存在种间和种内变异的重叠。4个片段的物种分辨率均较高,但与nrLSU相比,rpb1、tef1-α和rpb2具有更为明显的条形码间隔。鉴于rpb1比tef1-α和rpb2具有更高的种间变异和较低的种内变异,建议将rpb1作为牛肝菌属的核心条形码,tef1-α和rpb2可作为该属的辅助条形码。
iFlora is designed to integrate traditional taxonomy knowledge with DNA sequencing and biological infor- mation. Through a series of key technological innovations and integrations, the main objective of iFlora is to con- struct the next-generation Flora or intelligent Flora, which should fulfill the function of accurately and rapidly identif- ying species and acquiring related digital information. The most important and urgent task for iFlora development is to search for the standard DNA barcode to distinguish most of the plants and economically important mushrooms. To establish a standard DNA barcode for the edible boletes in Yunnan, samples of common boletes in the free markets regarded as four "species" by local mushroom hunters were collected and studied. Our date indicated that these four "species" in fact represent 12 distinct species. Furthermore, four candidate markers, the large subunit nuclear ribo- somal RNA (nrLSU), the translation elongation factor 1-alpha (tefl--α), the RNA polymerase II largest subunit (rpbl) and the RNA polymerase II second largest subunit (rpb2) were tested using the eukaryotic general primers for their feasibility as barcodes of the species of Boletus. This study indicates that the four candidate markers are of very high PCR amplification and sequencing success rate (100% and 100% respectively), and there are no over- lapping between intra- and inter- specific variation. All four candidate markers showed high species resolution. Com- pared with nrLSU, rpbl, tefl-α and rpb2 had much more clearly defined barcoding gaps. This study showed that rpbl can be used as a primary barcode marker considering that rpbl showed high sequence variation among species and low variation within species, while tefl-α and rpb2 can be proposed as supplementary barcodes for the boletes.
出处
《植物分类与资源学报》
CAS
CSCD
北大核心
2013年第6期725-732,共8页
Plant Diversity
基金
中国科学院昆明植物研究所"一三五规划"iFlora项目
中国科学院大科学装置开放研究项目(2009-LSFGBOWS-01)