道地药材板桥党参nrDNA-ITS区序列分析

[目的]研究道地药材板桥党参(Codonopsis tangshen Oliv.)叶nrDNA-ITS区的序列特征,为板桥党参分子鉴定提供依据。[方法]采用PCR直接测序技术测定板桥党参的nrDNA-ITS区核苷酸序列,并分析其序列组成。[结果]采用改良CTAB法提取得到样品的基因组DNA吸光值OD260/OD280比值在1.8～2.0,DNA条带清晰整齐,无明显的拖尾现象,表明所得DNA样品纯度和质量较好,符合试验要求。利用nrDNA-ITS序列通用引物进行PCR扩增反应,获得预期约800bp的双链产物。经过测序发现,板桥党参nrDNA-ITS1序列核苷酸序列长度为260bp,其G+C含量为52%,nrDNA-ITS2序列核苷酸序列长度为239bp,其G+C含量为60%;在GenBank上进行Blast对比分析,证实其属于党参科植物nrDNA-ITS序列,并已提交GenBank,注册登记号为GQ906566。[结论]DNA测序技术可作为准确而有效地鉴定板桥党参基原的分子鉴定方法,可为板桥党参分子鉴定提供基础性资料。

Camellia nitidissima与C.petelotii之间的关系研究——来自nrDNA ITS的证据

通过对 Camellia nitidissima Chi和 Camellia petelotii (Merr.) Sealy的核糖体 DNAITS区序列进行分析 ,结果表明两者的 ITS区序列存在一定的差异 ,Camellia nitidissima与Camellia tunghinensis,Camellia limonia和 Camellia pingguoensis的亲缘关系比与 Camelliapetelotii的关系更近 ,说明两者是相互独立的种。

宣化块菌形态特征的修订

宣化块菌(Tuber xuanhuaense)是2016年被报道的隶属于块菌科、块菌属的一个新物种,在发表新种时,宣化块菌子囊果包被结构被描述为疏丝组织,该组织被认为是该物种的鉴别特征之一。对近年(2016～2017)采集到该物种的22份标本研究发现,宣化块菌的包被结构在完全成熟时分化为两层,外层为拟薄壁组织,内层为疏丝组织。本研究依据模式标本和22份新采集的标本对宣化块菌的形态特征进行了修订描述,同时本研究显示宣化块菌是块菌属在中国华北地区最常见的物种之一,秋季常见于桦木(Betula spp.)、栎树(Quercus spp.)、松树(Pinus spp.)林地下土壤中。

Phylogenetic Study of <i>Acacia</i>Species Using the Molecular Marker

Acacia species are found at various arid and semiarid regions. Among the tree genera of family, Fabaceae, Acacia contains the highest number of species. We have collected different species of Acacia from various places of Saudi Arabia and reconstructed phylogeny for evaluation of genetic relationship among them. Internal transcribed spacer sequence of nrDNA (nrDNA-ITS) locus was used for the reconstruction of phylogeny among these species. Based on phylogenetic tree, Acacia etbaica and A. johnwoodii were close to each other. Similarly, A. ehrenbergiana and A. tortilis were close to each other. Thus, this gene locus was helpful in evaluating the genetic relationship among these species.