Micromorphological Study on Leaf Epidermis of Schizostachyum and Its Allies ( Poaceae: Bambusoideae)

Micromorphological characters of leaf epidermis of 16 published species from Schizostachy um Nees and its allies ( including Melocanna Trin. , Pseudostachyum Munro, Leptocanna Chia et H. L. Fung and Cephalostachyum Munro) were examined by both light and scanning electron microscopies. The results indicated that the papillae forms and distributional patterns on the abaxial surface were taxonomically informative at the generic level. The characters of papillae did not support Schiz ostachyum sensu lato; meanwhile, it was supported that Melocanna, Pseudostachyum and Cep halostachyum were better to be treated as separate genera respectively. Furthermore, it seemed to be more appropriate to place Leptocanna chinensis and Schizostachyum sanguineum in Cep halostachyum; and to place Cephalostachyum pergr acile and C1 virgatum in Schizostachy um .     

植物物种的快速鉴定与iFlora: DNA条形码在马先蒿属中的应用

DNA条形码技术就是利用一段较短的标准DNA序列对物种进行快速鉴定。与基于植物外部形态特征的传统分类鉴定方法相比, DNA条形码具有高效、准确,且易于实现自动化和标准化的特点。马先蒿属（Pedicularis L.）植物具对生（轮生）叶的种类70%以上分布在中国,近缘种间形态上非常相似,鉴定较为困难。研究选取马先蒿属具对生（轮生）叶类群43种164份样品,利用叶绿体基因（rbcL、matK、trnH psbA）和核基因（ITS）条形码片段,采用建树法和距离法检验4个条形码对这些物种的鉴定效果。结果表明,ITS片段用于建树法和距离法的鉴别率分别为81.40%和89.57%,其鉴别率高于3个叶绿体基因片段和任一基因片段的组合条码。另外,利用ITS成功解决了一些疑难种的分类问题。DNA条形码在马先蒿属研究中的实用性为新一代植物志（iFlora）实现物种的快速和准确鉴定提供了有力支持,并能为分类学、生态学、进化生物学、居群遗传学和保护遗传学等分支学科的研究提供重要信息。