濒危石斛兰野生原种的迁地保护与引种驯化

总结了连续几年的石斛兰引种与驯化实践,探讨了石斛兰生长习性与栽培措施的特殊性,对其抗寒、耐旱及繁殖特性及对应的管理方法进行了阐述。     

Germination and growth ofErythrorchis ochobinesis (Orchidaceae) accelerated by monokaryons and dikaryons ofLenzites betulinus andTrametes hirsuta

Four sib-monokaryons and two reconstituted dikaryons of two basidiomycetes,Lenzites betulinus andTrametes hiruta, accelerated the seed germination ofErythrorchis ochobiensis, an achlorophyllous orchid. All isolates ofL. betulinus and three isolates ofT. hirsuta induced the development of plants from germinated seeds. Although three monokaryotic isolates ofT. hirsuta failed to induce the development of plants, the reconstituted dikaryons induced the development.     

The impact of life form on the architecture of orchid mycorrhizal networks in tropical forest

Understanding the processes that determine the architecture of interaction networks represents a major challenge in ecology and evolutionary biology. One of the most important interactions involving plants is the interaction between plants and mycorrhizal fungi. While there is a mounting body of research that has studied the architecture of plant–fungus interaction networks, less is known about the potential factors that drive network architecture. In this study, we described the architecture of the network of interactions between mycorrhizal fungi and 44 orchid species that represented different life forms and co‐occurred in tropical forest and assessed the relative importance of ecological, evolutionary and co‐evolutionary mechanisms determining network architecture. We found 87 different fungal operational taxonomic units (OTUs), most of which were members of the Tulasnellaceae. Most orchid species associated with multiple fungi simultaneously, indicating that extreme host selectivity was rare. However, an increasing specificity towards Tulasnellaceae fungal associates from terrestrial to epiphytic and lithophytic orchids was observed. The network of interactions showed an association pattern that was significantly modular (M = 0.7389, M_random = 0.6998) and nested (NODF = 5.53, p < 0.05). Terrestrial orchids had almost no links to modules containing epiphytic or lithophytic orchids, while modules containing epiphytic orchids also contained lithophytic orchids. Within each life form several modules were observed, suggesting that the processes that organize orchid–fungus interactions are independent of life form. The overall phylogenetic signal for both partners in the interaction network was very weak. Overall, these results indicate that tropical orchids associate with a wide number of mycorrhizal fungi and that ecological rather than phylogenetic constraints determine network architecture.     

中国中部太白山不同海拔杜鹃兰根部内生真菌多样性

本研究以太白山自然保护区蒿坪站杜鹃兰Cremastra appendiculata为材料,采用菌丝团和根组织分离法进行真菌分离,并用ITS序列分子鉴定;用变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)分析根部内生真菌多样性,研究海拔和根际土理化性质对真菌多样...     

兰花病毒检测技术研究进展(综述)

综述近年来应用于兰花病毒检测的各种技术。较详细地介绍了血清学方法和分子生物学方法的应用情况;简述一些常用检测方法的优缺点,为在兰花生产中建立快速简便的病毒检测技术提供参考。     

Multiple shoot formation and plant regeneration from stem nodal explants of <Emphasis Type="Italic">Paphiopedilum</Emphasis> orchids

Summary Stem nodal explants of Paphiopedilum philippinense hybrids (hybrid PH59 and PH60) directly formed shoots when cultured on a modified half-strength Murashige and Skoog (1962) basal medium supplemented with a combination of 2,4-dichlorophenoxyacetic acid (2,4-D: 4.52 and 45.25 μM) and 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea (TDZ; 0.45 and 4.54 μM) for 6 mo. On hormone-free basal medium, the percentages of explants with shoots were 33.3% and 0% and the shoot numbers per explant were 1 and 0 in hybrid PH59 and hybrid PH60, respectively. In hybrid PH59, 4.52 μM 2,4-D plus 0.45μM TDZ induced a higher percentage of explants with shoots and shoot number per explant than did the hormone-free treatment. In hybrid PH60, although 4.52 μM 2,4-D and 0.45 μM TDZ promoted shoot formation, the highest shoot number was found with 4.52 μM 2,4-D alone. Plantlets, each having several roots, were obtained from regenerated shoots after transferring onto hormone-free basal medium for 3 mo. The plantlets were potted in sphagnum moss, and acclimatized well in a greenhouse.     

广东山区兰科植物区系的研究

初步统计 ,广东山区共有兰科植物 71属 2 0 8种。其中以热带分布属 4 7属 ( 66.2 % )为主 ,占绝对优势 ,其次为热带—亚热带属 1 3属 ( 1 8.3% )。主要属为虾脊兰属、羊耳蒜属、玉凤花属、石斛属、兰属、石豆兰属 ,其中 2属为世界分布属 ,2属为热带分布属 ,2属为热带—亚热带分布属。广东山区兰科植物区系的地理成分较为复杂、多样 ,以热带亚洲成分 (占 39.4 % )为主导成分 ,其次为热带亚洲至热带大洋洲分布成分 ( 1 6.9% )。广东山区没有特有属 ,但特有种丰富 ,产中国特有种 39种 (占 1 8.8% ) ,其中广东特有种 6种 (占 2 .9% )。广东山区具有兰科植物从最原始到最进化各类型的代表。区系成份比较表明 ,本区与云南、广西和中南半岛兰科植物区系有较密切的联系。结果表明本区兰科植物区系的古老原始性 ;具有从热带向亚热带过渡的特点 ;与热带亚洲兰科植物区系具有密切的关系 ;可能是中国兰科植物演化中心的一部分。     

Agrobacterium tumefaciens-mediated transformation of Dendrobium lasianthera J.J.Sm: An important medicinal orchid

A protocol for genetic transformation mediated by Agrobacterium tumefaciens and production of transgenic Dendrobium lasianthera has been developed for the first time. The 8-week-old protocorm explants were used as target of transformation with Agrobacterium tumefaciens strain LBA4404 carrying plasmid pG35SKNAT1. Several parameters such as infection period, Agrobacterium density, concentration of acetosyringone, and co-cultivation period were evaluated for the transformation efficiency. The data were analyzed using one-way analysis of variance (ANOVA) and Duncan's Multiple Range Test (DMRT) with p?<?0.05. Subsequently, KNAT1 gene expression was confirmed by polymerase chain reaction (PCR) analysis. The highest efficiency of transformation (70%) obtained from protocorm explants infected with Agrobacterium culture was at the OD₆₀₀ concentration of 0.6 for 30?min, and co-cultivated with acetosyringone 100?µM for 5?days. The results of confirmation by PCR analysis show that the KNAT1 gene has been integrated and expressed in the genome of Dendrobium lasianthera transgenic.     

Direct somatic embryogenesis and plant regeneration from leaf explants of Phalaenopsis amabilis

Leaf explants of Phalaenopsis amabilis var. formosa formed clusters of somatic embryos directly from epidermal cells without an intervening callus within 20 – 30 d when cultured on 1/2-strength modified Murashige and Skoog medium supplemented with 0.1, 1 and 3 mg dm⁻³ TDZ. Repetitive production of embryos involved secondary embryogenesis could be obtained by culturing segments of embryogenic masses on TDZ-containing media. Plantlet conversion from embryos was successfully achieved on regulator-free growth medium.     

Induction of repetitive embryogenesis from seed-derived protocorms of <Emphasis Type="Italic">Phalaenopsis amabilis</Emphasis> var. <Emphasis Type="Italic">Formosa</Emphasis> shimadzu

Summary An in vitro culture procedure was established for repetitive embryogenesis and plant regeneration from seed-derived protocorms of Phalaenopsis amabilis var. formosa Shimadzu (Orchidaceae). Seed-derived protocorms were cultured on modified half-strength Murashige and Skoog (1962) basal medium (1/2MS) devoid of plant growth regulators. After 45 d, 28.1% of protocorms formed embryos from their posterior regions. 1-Phenyl-3-(1,2,3-thiadiazol-5-yl)-urea (TDZ; 0.45, 4.54, and 13.62 μM) promoted direct embryo formation. The best response was at 13.62 μM TDZ, and 100% of the protocorms formed a mean number of 13.5 embryos after 45d of culture. By contrast, naphthaleneacetic acid (NAA) at 0.54 and 5.37 μM inhibited direct embryo formation. On basal medium devoid of plant growth regulators, 18.8% of primary proliferating embryos could form more embryos. TDZ (0.45, 4.54, and 13.62 μM) also promoted this process. Proliferating embryos/protocorms were transferred to basal medium devoid of plant growth regulators for plantlet formation. Plantlets were successfully obtained from the embryos after 4–6 wk. Following subculture every 6 wk for three passages, the plantlets were transferred to sphagnum moss in a container for acclimatization in the greenhouse. The survival rate was 100%.     

广东国兰虫害发生调查

2009年12月至2013年3月,调查了广东省国兰虫害种类及其危害,调查结果表明：在广东为害国兰的节肢动物有：半翅目的牡蛎蚧Lepidosaphinae、褐软蜡蚧Coccus hesperidum (Linnaeus)和蚜虫Aphidae、缨翅目的兰花蓟马Dichromothrips corbetti (Priesner)、直翅目的Locustoidea、螽斯Tettigoniidae、鳞翅目的蓑蛾Psychidae以及软体动物蜗牛和蛞蝓等9种（类）有害生物,并对国兰虫害的为害状和发生情况进行了简要描述,以期为国兰虫害的诊断和预防提供指导。     

Pollinator rarity as a threat to a plant with a specialized pollination system

An increasing diversity of highly specialized pollination systems are being discovered, many of which are likely to be vulnerable to anthropogenic landscape modification. Here, we investigate if a specialized pollination system limits the persistence of Caladenia huegelii (Orchidaceae), an endangered species pollinated by sexual deception of thynnine wasps. Once locally common in part of its geographical range, C. huegelii is now largely restricted to small habitat remnants in urban areas. Pollinator surveys coupled with DNA barcoding detected a single pollinator taxon, a small form of Macrothynnus insignis. Phylogenetic analysis revealed that small M. insignis from within the range of C. huegelii are strongly divergent from other wasp populations, suggesting that some reproductive isolation may exist. Although common in intact landscapes outside the range of C. huegelli, small M. insignis individuals were recorded at only 4% of sites in suitable C. huegelii habitat. Accordingly, reproductive success in C. huegelii was low compared with related Caladenia spp., with 33–60% of populations failing to set fruit in any given year. As such, populations are likely to now persist primarily through individual plant longevity rather than reproduction. Due to the low reproductive success of C. huegelii, ongoing human intervention will almost certainly be needed to sustain the species. Future research will need to focus on optimizing hand pollination to maintain reproduction and high seed fitness. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 511–525.     

Ethylene induced cyanide resistant respiration in orchid petal cells

Respiration of isolated Aranda orchid petal cells increased markedly after cut flowers were treated with ethylene. An increase in respiration was observed 15 to 20h after treatment which was further enhanced in the presence of oxygen and ethylene. Ethylene induces the development of a cyanide resistant pathway in fully opened orchid flower tissues where the cyanide resistant capacity is negligible. However, there appears a shift back to the cyanide sensitive pathway some time after induction.     

Development and characterization of microsatellites in Vanda varieties

The orchid genus Vanda includes more than 70 monopodial species and numerous hybrids. The aim of this study was to develop microsatellite markers for this horticultural valuable genus. Thirteen polymorphic microsatellite markers were isolated from the variety Vanda Miss Joaquim and were characterized in four Vanda species, 11 Vanda hybrids, and one Aranda intergenus hybrid. Populations from three species were also analysed. Number of alleles ranged from two to 19. For the V. sumatrana population, the expected heterozygosity ranged from 0 to 0.76 (mean 0.31) and the observed heterozygosity ranged from 0 to 1 (mean 0.36). All the varieties tested were distinct from one another (similarity index < 0.8). These microsatellites could be used for studying genetic diversity and population structure of wild populations within the orchid genus Vanda, as well as for distinguishing cultured Vanda varieties.     

Mass multiplication of protocorm-like bodies using bioreactor system and subsequent plant regeneration in Phalaenopsis

Protocorm-like bodies (PLBs) formed on leaf segmentsin vitro were used as explants for bioreactor cultures. Continuous immersion cultures (air lift column and air lift-balloon bioreactor), and temporary immersion cultures (with or without charcoal filter attached) were used for the culture of PLB sections. A temporary immersion culture with charcoal filter attached was most suitable for PLB culture. About 18,000 PLBs were harvested from 20 g of inoculum (∼1000 PLB sections) in 2 l Hyponex medium after 8 weeks of incubation. Aeration in a bioreactor at 0.5 or 2.0 volume of air per volume of medium min⁻¹ (vvm) yielded similar levels of biomass production. PLBs grown in bioreactors were cultured on solid Murashige and Skoog, Vacin and Went, Knudson C, Lindemann and Hyponex media. Hyponex medium was found to be suitable for conversion of PLBs into plantlets and 83% of PLBs transformed into plantlets on this medium. The feasibility of using PLBs for large-scale micropropagation was evaluated for scaled-up liquid cultures in bioreactors, rate of proliferation, and regeneration. This revised version was published online in June 2006 with corrections to the Cover Date.