Bauhinia blakeana Dunn is the Hong Kong Special Administrative Region emblem and a popular horticultural species in many Asian countries. It was first described as a new species from Hong Kong almost a century ago. Th...Bauhinia blakeana Dunn is the Hong Kong Special Administrative Region emblem and a popular horticultural species in many Asian countries. It was first described as a new species from Hong Kong almost a century ago. This plant is sterile and has long been considered a hybrid, possibly from two related species, B. purpurea and B. variegata. However, not much evidence based on molecular methods was available to support this hypothesis. In this study, sequences of internal transcribed spacer I （ITS1）, rbcL and atpB-rbcL intergenic spacer for five Bauhinia species and two varieties of one of the species were determined and compared. There were two types of ITS1 sequences in B. blakeana, one indistinguishable from that of B. purpurea and the other one identical to that of B. variegata. This confirmed that B. blakeana was a hybrid of these two species. Chloroplast atpB-rbcL intergenic spacer sequence of B. blakeana was identical to that of B. purpurea, indicating that B. purpurea was the female parent. The hybridization event seemed to occur only recently and was a rare incident. Its occurrence was likely facilitated by interspecific pollen competition. It appeared that human efforts played a crucial role in the preservation and ubiquity of B. blakeana.展开更多
应用PCR技术对在鸭粪中发现的疑似环孢子虫的18 S rDNA部分基因和ITS-1+基因进行了扩增,将扩增出的片段纯化后连接至pMD-18T载体上,选取阳性克隆进行序列测定,并利用NCBI在线BLAST程序和MEGA 4软件对测序结果进行了同源性比较和系统发...应用PCR技术对在鸭粪中发现的疑似环孢子虫的18 S rDNA部分基因和ITS-1+基因进行了扩增,将扩增出的片段纯化后连接至pMD-18T载体上,选取阳性克隆进行序列测定,并利用NCBI在线BLAST程序和MEGA 4软件对测序结果进行了同源性比较和系统发育树构建。结果显示,测得的18 SrDNA序列与环孢子虫的相似性最高(98%),且在系统树中位于同一分支上;测得的ITS-1序列高度特异,在GenBank中未发现同源性序列,可以确定其为环孢子虫的一个新种,暂命名为鸭源环孢子虫。展开更多
基金Partially Supported by the Chinese University of Hong Kong Strategic Research Programme.
文摘Bauhinia blakeana Dunn is the Hong Kong Special Administrative Region emblem and a popular horticultural species in many Asian countries. It was first described as a new species from Hong Kong almost a century ago. This plant is sterile and has long been considered a hybrid, possibly from two related species, B. purpurea and B. variegata. However, not much evidence based on molecular methods was available to support this hypothesis. In this study, sequences of internal transcribed spacer I （ITS1）, rbcL and atpB-rbcL intergenic spacer for five Bauhinia species and two varieties of one of the species were determined and compared. There were two types of ITS1 sequences in B. blakeana, one indistinguishable from that of B. purpurea and the other one identical to that of B. variegata. This confirmed that B. blakeana was a hybrid of these two species. Chloroplast atpB-rbcL intergenic spacer sequence of B. blakeana was identical to that of B. purpurea, indicating that B. purpurea was the female parent. The hybridization event seemed to occur only recently and was a rare incident. Its occurrence was likely facilitated by interspecific pollen competition. It appeared that human efforts played a crucial role in the preservation and ubiquity of B. blakeana.
基金This research was funded by the grant fromthe National Natural Science Foundation of China (30499341 ,30270221) the Excellent YouthFoundationin Anhui Province (04043050)+2 种基金the Natural Science Foundation of Educational Committee of Anhui Province (2004sys003) the Foundation of Provincial Key Laboratory of Conservation and Utilizationfor I mportant Biological Resourcein Anhui the Special Foun-dation of Anhui Normal University
文摘应用PCR技术对在鸭粪中发现的疑似环孢子虫的18 S rDNA部分基因和ITS-1+基因进行了扩增,将扩增出的片段纯化后连接至pMD-18T载体上,选取阳性克隆进行序列测定,并利用NCBI在线BLAST程序和MEGA 4软件对测序结果进行了同源性比较和系统发育树构建。结果显示,测得的18 SrDNA序列与环孢子虫的相似性最高(98%),且在系统树中位于同一分支上;测得的ITS-1序列高度特异,在GenBank中未发现同源性序列,可以确定其为环孢子虫的一个新种,暂命名为鸭源环孢子虫。
