中国兜兰属植物生态地理分布

分析了国产兜兰属植物的生态地理分布特点和发展趋势及兜兰属植物的系统演化趋势与生态地理环境的关系。国产兜兰野生种共有 18种 ,主要分布于热带过渡地区 (南亚热带 ) ,主产西南各省区 ;大多数种类生长于石灰岩山地 ,多为半附生兰 ,呈丛生生长 ,另一部分生长于酸性砂岩面的腐叶土上 ,多为地生兰 ,呈单株生长或分蘖状散生 ;大部分兜兰分布于较高海拔地区 ;国产兜兰属中最原始的短瓣亚属绝大部分种类仅分布在滇东南地区与贵州、广西连成一片的岩溶地貌的石灰岩地区 ,而兜兰属中较进化的兜兰亚属大部分种类在本区皆有分布。以上说明滇东南的石灰岩地区可能是兜兰属的起源中心和演化中心 ,中国的南亚热带地区是兜兰属植物的生态多样性中心     

Paphiopedilum microchilum,a new species of Orchidaceae from Yunnan,China

Paphiopedilum microchilum Z. J. Liu et S. C. Chen from Yunnan, China, is described and illustrated. Its affinity with Paph. wardii Summerh. is briefly discussed.     

Paphiopedilum× yingjiangense,a New Hybrid of Orchidaceae from China

Paphiopedilum× yingjiangense Z . J . Liu et S . C . Chen , a new hybrid from China, is described and illustrated. This entity may be a natural hybrid between Paphiopedilum villosum and P . wardii . It differs from the former by having obscurely deep and light green nets on upper surface of leaves, a pale yellow-green flower with fine dark purple spots on petals and lower part of dorsal sepal and broadly ovate-orbicular staminode without a central glossy knob; from the latter by longer leaves not obviously mottled pale and dark bluish green above nor densely spotted purple below, a much larger flower, and a broadly ovate-orbicular staminode .     

中国兜兰属23种植物叶表皮微形态特征初步研究

利用光学显微镜对兜兰属（Paphiopedilum）23种植物叶片进行观察,并对其中14种叶表皮微形态性状测量数值进行主成分分析和聚类分析。结果显示：23种植物叶表皮均有较厚角质层,上表皮细胞多为多边形和卵圆形,无气孔分布,部分种叶上表皮细胞有表皮毛,表皮细胞表面会形成乳突状突起,并且一个细胞只形成一个乳突,多数种的叶表面会呈现明显或不明显的龟背隆起,细胞大小及细胞密度在不同种之间存在极大差异;气孔器广泛分布于下表皮,由保卫细胞构成,排列无规则,外壁呈不同程度加厚。主成分分析表明,特征值大于1的主成分共有4个,基于4个主成分进行聚类,结果可将兜兰属分为两大类,即宽瓣亚属（Brachypetalum）和兜兰亚属（Paphiopedilum）,小萼亚属（Parvisepalum）被聚类于宽瓣亚属中。本研究表明兜兰属种间部分叶表皮形态特征具有一定的稳定性,叶片表皮细胞的形状与垂周壁式样变异不大;受环境气候的影响,气孔器大小及气孔密度在不同种间的分布不同,表现出种间多样性,因此这部分叶表皮微形态特征可作为其分类的参考依据。     

中国新分布种海伦兜兰的濒危状况

海伦兜兰Paphiopedilum helenae Aver.为中国新记录种。本种中萼片黄色,花瓣橙色,狭长圆形或略带匙形,边缘直,唇瓣橙褐色,退化雄蕊为近圆形。文章首次报道了海伦兜兰在中国新分布点的居群大小和繁育现状,并对其生境、伴生植物等作了详细描述。海伦兜兰所在的森林群落目前保护状况良好,但由于该地靠近村寨和公路,又不在保护区内,海伦兜兰居群仍然面临潜在的威胁。考虑到海伦兜兰在越南已遭受过度采集,建议进一步加强对该新分布兜兰属Pahiopdeilum植物的保护和监测。     

DNA barcoding of endangered Indian Paphiopedilum species

The indiscriminate collections of Paphiopedilum species from the wild for their exotic ornamental flowers have rendered these plants endangered. Although the trade of these endangered species from the wild is strictly forbidden, it continues unabated in one or other forms that elude the current identification methods. DNA barcoding that offers identification of a species even if only a small fragment of the organism at any stage of development is available could be of great utility in scrutinizing the illegal trade of both endangered plant and animal species. Therefore, this study was undertaken to develop DNA barcodes of Indian species of Paphiopedilum along with their three natural hybrids using loci from both the chloroplast and nuclear genomes. The five loci tested for their potential as effective barcodes were RNA polymerase-β subunit (rpoB), RNA polymerase-β' subunit (rpoC1), Rubisco large subunit (rbcL) and maturase K (matK) from the chloroplast genome and nuclear ribosomal internal transcribed spacer (nrITS) from the nuclear genome. The intra- and inter-specific divergence values and species discrimination rates were calculated by Kimura 2 parameter (K2P) method using mega 4.0. The matK with 0.9% average inter-specific divergence value yielded 100% species resolution, thus could distinguish all the eight species of Paphiopedilum unequivocally. The species identification capability of these sequences was further confirmed as each of the matK sequences was found to be unique for the species when a blast analysis of these sequences was carried out on NCBI. nrITS, although had 4.4% average inter-specific divergence value, afforded only 50% species resolution. DNA barcodes of the three hybrids also reflected their parentage.     

ISSR and SRAP Markers Reveal Genetic Diversity and Population Structure of an Endangered Slipper Orchid,Paphiopedilum micranthum (Orchidaceae)

Paphiopedilum micranthum is an endangered pink slipper orchid mainly distributed in the limestone areas of southwestern China. Wild populations of this species have been seriously threatened by excessive collections, rampant smuggling for export, and habitat destruction. We used 15 ISSR markers and 11 SRAP markers to investigate the genetic diversity and structure of 15 natural populations. A high degree of diversity was observed at the species level (ISSR: PPB=9166%, He=03839; SRAP: PPB=9929%, He=02806). Certain degree of genetic differentiation among populations (ISSR: Gst=02577; SRAP: Gst=02383) was detected maybe caused by low gene flow (ISSR: Nm=07201; SRAP: Nm=07991). Consistent with the results of Principal Coordinate Analysis, the UPGMA dendrogram analysis divided the 15 populations into two main clades. In addition to geographic distance, the difference in elevation was another natural factor contributing to this differentiation. Knowledge about genetic diversity and structure gained from our study will be beneficial for the development of reasonable and efficient strategies to conserve this endangered species.     

Interaction between Endophytic Fungi and Seedlings of Two Species of Paphiopedilum during Symbiotic Culture

Two fungi PM 1 and PA 1 were isolated from P.micranthum and P.armeniacum, respectively, the former belonged to Epulorhiza while the latter belonged to Tulasnella calospora. In this study, seedlings of P.armeniacum and P.micranthum were inoculated with PM 1 on DE medium, the biomass and the content of Ca, Mn of both P.armeniacum and P.micranthum seedlings were higher than those in the control seedlings, which indicated that PM 1 could improve the growth of those species. Seedlings of P.armeniacum and P.micranthum were inoculated with PA 1 on DE medium, the biomass in both species was no difference with those in the control ones. But PA 1 enhanced the dry weight of P.armeniacum according to the rate of dry weight increase. The impact of PM 1 on P.micranthum was higher than on P.armeniacum, while PA 1 impacted conversely, which demonstrated that fungi had stronger improving effect only on its own host plants instead of any other orchids. P.armeniacum seedlings wereinoculated with PM 1 and PA 1 on Harvais medium. The growth of seedlings was inhibited by fungi. The results indicated that nutrient level of medium played an important role in affecting the symbiotic relationship between P.armeniacum seedings and endophytic fungi. Poor nutrient medium was beneficial to the symbiotic relationship and nutrient rich medium was not conducive to the symbiosis.     

Asymbiotic Seed Germination and in vitro Seedling Rapid Development of Paphiopedilum spicerianum

In this paper, we studied the asymbiotic seed germination and seedling development of Paphiopedilum spicerianum, a wild plant with extremely small populations (PSESP) in China. By analogizing the influences of different media, seed maturity, pretreatments and lights on the seed germination, the results showed that the best germination condition is using the seeds at 270 days after pollination, pretreating with 1% NaOCl for 40 min, on the 1/4MS+10% coconut water medium under 24 hours darkness for 4 weeks. For seedling formation, 30g·L-1 Hyponex No 1 medium with 10mg·L-1 α naphthlene acetic acid, 05g·L-1 activated charcoal and 10% banana homogenate was the most effective. For seedling development, the same medium used for seedling formation with supplemented 10g·L-1 6 benzyladenine was most suitable.