越南荨麻科楼梯草属和赤车属植物新记录

报道了7个楼梯草属和赤车属植物(荨麻科)新纪录,它们分别为锐齿楼梯草(E. cyrtandrifolium),变黄楼梯草(E. xanthophyllum),对叶楼梯草(E. sinense),宽叶楼梯草(E. platyphyllum),托叶楼梯草(E. nasutum),短叶赤车(P. brevifolia)和华南赤车(P. grijsii)。列出了各个物种的标本引证和地理分布情况。     

西藏紫草科1新记录属——微果草属

该文报道了西藏地区紫草科1新记录属微果草属(Microcaryum)及1新记录种微果草(Microcaryum pygmaeum (Clarke)Johnst.)。该种发现于西藏隆子县,生于海拔约5 000 m的高山草甸。研究了其外部形态、小坚果微形态及花粉形态,并与形态相近种毛果草 （Lasiocaryum densiflorum (Duthie)Johnst.） 进行了比较。凭证标本保存于北京师范大学动植物标本馆植物标本室(BNU)。     

阿尔泰山两河源国家级自然保护区鼓藻类中国新记录

分别于2016年7月和2017年8月在阿尔泰山两河源国家级自然保护区采集鼓藻类植物标本,经显微镜观察,发现鼓藻类（绿藻门）中国新记录植物5个分类单位,隶属于4个属,包括4种1变种：膨大新月藻（新拟）（Closterium tumidulum Gay）、钝齿宽带鼓藻（新拟）［Pleurotaenium crenulatum (Ralfs) Rabenhorst］、克塞凹顶鼓藻（新拟）（Euastrum coeselii Kouwets）、圆齿状鼓藻（新拟）（Cosmarium crenulatum Ngeli）和肾形鼓藻收缩变种（新拟）（Cosmarium reniforme var. compressum Nordstedt）。对这些新记录植物的形态学特征进行了详细的描述,并提供了光镜照片及手绘图。     

甘肃省小陇山地区鸢尾属植物资源调查及2个新记录种

本文报道了甘肃小陇山地区鸢尾科（Iridaceae）鸢尾属（Iris L.）植物2个新分布记录种：长柄鸢尾（Iris henryi Baker）和薄叶鸢尾（Iris leptophylla Lingelsh.）。通过整理重新编制了小陇山地区鸢尾属植物的分种检索表。两种植物的发现进一步丰富了鸢尾属在全国的分布格局和本属在秦岭地区的种类,并为小陇山地区的物种多样性研究提供了新的分布信息。凭证标本存放于陇南师范高等专科学校植物标本室。     

中国毛茛科翠雀属的分类学研究(十三):狭序翠雀花的名实订正

发现根据甘肃南部标本描述的毛茛科狭序翠雀花（Delphinium angustipaniculatum W.T.Wang）与此前记载分布于甘肃南部和四川北部的松潘翠雀花（D.sutchuenense Franch.）属于同一种植物,故将前者处理为后者的异名。讨论了松潘翠雀花与其可能的近缘种秦岭翠雀花（D.giraldii Diels）和疏花翠雀花（D.sparsiflorum Maxim.）的形态区别。     

贵州省新记录植物

报道了产自贵州赤水桫椤国家级自然保护区内的贵州省7种新记录植物,分别是狭冠长蒴苣苔（Didymocarpus stenanthos Clarke）、芒毛苣苔（Aeschynanthus acuminatus Wall.ex A.DC.）、石蜘蛛（Pinellia integrifolia N.E.Brown）、网子度量草（Mitreola reticulata Tirela-Roudet）、棒距虾脊兰（Calanthe clavata Lindl.）、金长莲（Staurogyne sichuanica H.S.Lo）和石萝藦（Pentasacme championii Benth.）,其中叉柱花属(Staurogyne Wall.)和石萝藦属(Pentasacme Wall.ex Wight)为贵州省新记录属,凭证标本均保存在中南林业科技大学植物标本室(CSFI)。这些植物新的地理分布对于贵州北部植物区系和丹霞地貌植被研究均有重要意义。     

湖北省被子植物1个新记录属和5个新记录种

报道了湖北省被子植物1个新记录属：葛缕子属（Carum L.）;5个新记录种：田葛缕子（Carum buriaticum Turcz.）、南川鹿药（Maianthemum nanchuanense H. Li & J. L. Huang）、宽叶香茶菜〔Isodon latifolius （C. Y. Wu & H. W. Li） H. Hara〕、广东新耳草〔Neanotis kwangtungensis （Merrill & F. P. Metcalf） W. H. Lewis〕和毛柱郁李（Prunus pogonostyla Maxim.）。相关凭证标本保存于中国科学院武汉植物园标本馆（HIB）。     

半干旱草地不同植物枯落物分解对放牧和封育的响应

为探究放牧和封育对半干旱草地植物枯落物分解的影响,选取赖草、牛枝子及其混合物为研究对象,调查了不同网孔分解袋中宁夏半干旱草地植物枯落物分解特征及对放牧和封育的响应规律。结果表明：（1）放牧样地250目网孔中,枯落物质量残留率表现为牛枝子显著高于赖草和混合物（P<0.05）,而在放牧样地30目网孔、封育样地2种网孔中,枯落物质量残留率均表现为3种枯落物间无显著差异。（2）250目网孔中,放牧和封育样地枯落物分解衰减常数均表现为混合物显著高于牛枝子,而赖草居中;并且,牛枝子枯落物分解衰减常数表现为封育样地显著高于放牧样地。30目网孔中,放牧和封育样地枯落物分解衰减常数均表现为赖草、混合物显著高于牛枝子（P<0.05）;并且,牛枝子枯落物分解衰减常数表现为封育样地显著高于放牧样地（P<0.05）。（3）在放牧样地,仅牛枝子枯落物R_m表现为30目显著低于250目网孔（P<0.05）,k表现为30目显著高于250目网孔（P<0.05）;土壤动物对枯落物分解的贡献率表现为混合物显著低于牛枝子,赖草居中（P<0.05）。而在封育样地,仅牛枝子枯落物k表现为30目显著高于250目网孔（P<0.05）;土壤动物对枯落物分解的贡献率表现为混合物和牛枝子均显著高于赖草,且混合枯落物的土壤动物贡献率表现为封育样地显著高于放牧样地（P<0.05）。（4）枯落物残留率与其初始N、P、木质素/N、C/P呈显著相关性（P<0.05）;枯落物分解衰减常数与其初始N、P、木质素、N/P、C/P和木质素/P间均呈显著相关性（P<0.05）。研究表明,植物种类组成显著影响枯落物的残留率和分解衰减常数。放牧与封育管理通过影响网孔中土壤动物分布来调控半干旱区草地植物枯落物的分解,而且封育管理更有利于促进土壤动物对低质量枯落物（牛枝子）的分解。     

崆峒山国家级风景名胜区野生植物群落特征研究

采用样地调查的方法对崆峒山国家级风景名胜区野生植物群落进行野外调查，共布设26个20 m×20 m的标准样地，共调查野生维管植物86科230属323种。对植物群落外貌分析发现，研究区野生群落的外貌结构层次清晰，其中高位芽占比达到43.34%，地面芽植物占比23.30%，地上芽植物和一年生植物分别占比为18.58%和8.98%，地下芽植物最少，仅有5.80%；主要以纸质4级中型叶的中高位芽植物和草质3级小型叶的地面芽植物为主，反映出半湿润暖温带气候区所具有的谱系特征。野生植物群落在垂直结构上，乔木层以青榨槭（Acer davidii）、鹅耳枥（Carpinus turczaninowii）、少脉椴（Tilia paucicostata）、毛桃（Prunus davidiana）等为主要的优势种；灌木层以箭竹（Fargesia nitida）、毛叶欧李（Cerasus dictyoneura）、栓翅卫矛（Euonymus phellomanus）分布密集，为主要的优势种；草本层中除了有较多的蕨类草本植物外，其优势种主要有地丁草（Corydalis bungeana）、委陵菜（Potentilla chinensis）等。在径级结构分析中，径级分布比较规整，随着径级等级的增加从Ⅰ至Ⅴ，植株数整体呈急剧下降的趋势。采用Margalef丰富度、Shannon-Wiener多样性、Simpson优势度和Pielou均匀度指数对崆峒山国家级风景名胜区典型野生植物群落进行分析，不同的野生群落物种多样性存在明显差异，但四个指数在群落层次的变化趋势中均表现为乔木层>灌木层>草本层。     

油菜类型和品种对外来入侵杂草小子虉草的替代控制作用

外来入侵植物小子虉草（Phalaris minor Retz.）是世界公认的冬季农田恶性杂草,掌握农作物对其替代控制作用具有重要的研究价值。前期研究表明,油菜是替代控制小子虉草的优良农作物,然而,目前尚不清楚油菜类型与品种对其控制能力的影响。为此选取与小子虉草同域发生的不同类型（白菜型油菜、芥菜型油菜和甘蓝型油菜）油菜品种各3种,通过田间小区实验和室内化感作用测定,对比研究其对小子虉草的生长、繁殖、表型以及化感作用的影响。田间实验显示：竞争方式（种内或种间竞争）和油菜类型对小子虉草的地上生物量、种子数、株高、分枝数、叶面积和比叶面积存在极显著（P=0.0001）影响;而油菜品种对小子虉草的地上生物量（P=0.6064）、种子数（P=0.3577）、株高（P=0.4279）、分枝数（P=0.6357）、叶面积（P=0.8839）和比叶面积（P=0.3424）均无显著影响。3种类型油菜对小子虉草生长、繁殖以及表型的影响存在明显差异,其中芥菜型油菜对小子虉草的上述指标的影响最强,而白菜型油菜的影响最弱。室内生物测定显示,油菜对小子虉草具有化感抑制作用,当供试油菜叶片水提液浓度为0.1 g/mL时,小子虉草种子的萌发和幼苗的株高、根长、生物量均被显著抑制;研究也表明不同类型油菜对小子虉草的化感作用显著不同,同等条件下,芥菜型油菜对小子虉草的化感抑制作用最强。综上所述,油菜类型对外来入侵小子虉草的控制作用存在显著差异,其中芥菜型油菜对植物小子虉草的替代控制作用明显优于白菜型油菜和甘蓝型油菜,而其强的化感抑草特性或许是其强控草能力的原因之一。另外,本研究也为进一步利用油菜替代控制入侵植物小子虉草提供了参考。     

Vermicomposting in the management of pig-waste in Hong Kong

The treatment and disposal of pig-waste in Hong Kong has received much attention in recent years but, following any of the presently used treatment processes, solids remain to be further stabilized. Vermicomposting is a waste stabilization technique which converts waste into potentially recyclable materials such as worm protein and worm casts. The earthworm, Pheretima asiatica, can stabilize most of the solids arising from the treatment of pig-waste, including raw pig manure, suggesting that vermicomposting has a high potential as a unit process in the management of pig-waste in Hong Kong.S.H. Wong is with the Environmental Protection Department, Hong Kong; and D.A. Griffiths is with the Department of Botany, University of Hong Kong, Hong Kong.     

香港鹅耳枥(桦木科)的群落特征

为保护香港特有植物香港鹅耳枥,基于典型样地调查,对香港鹅耳枥所在群落进行了研究。结果表明,在225 m2的样地内,有维管植物37科66属68种。建群种为香港鹅耳枥,个体高度最高3 m,所在群落植株平均高度0.92 m,分层不明显。位于中国香港岛的香港鹅耳枥处于衰退状态,小个体极少。因此,建议采取就地保护和迁地保护措施,以重建种群。     

Rodent Diversity in a Highly Degraded Tropical Landscape: Hong Kong, South China

The diverse ecological roles played by different rodent species mean that the loss of some species and superabundance of others could potentially influence a wide range of ecological processes. Hong Kong (22° N, 114° E), with seven million people in a land area of 1100 km², could be considered a `worst case scenario' for the survival of mammalian diversity. Existing information on rodents in Hong Kong was compiled from previous published and unpublished studies, and additional trapping was conducted at 17 non-urban sites. The rodent fauna of modern Hong Kong consists of eight species of rats and mice (Bandicota indica, Mus caroli, M. musculus, Niviventer fulvescens, Rattus norvegicus, R. rattus, R. tanezumi, R. sikkimensis: Muridae), one porcupine (Hystrix brachyura: Hystricidae), and one recently introduced tree squirrel (Callosciurus erythraeus: Sciuridae). Six of the murids are urban or agricultural commensals, so only the porcupine and two murids, N. fulvescens and R. sikkimensis, are likely survivors of Hong Kong's pre-deforestation native rodent fauna. The two murids co-dominate in forest and shrubland, but can also move through grassland, which has probably enabled their survival through repeated cycles of fragmentation and regrowth. Additional forest rodents that may have inhabited Hong Kong in the past are tentatively identified from information on their recent distributions in the region. One possible ecological consequence of Hong Kong's depleted rodent fauna is a shift in the balance between seed predation and seed dispersal, in favor of the former.     

Purification and properties of β-amylase from Bacillus circulans S31

A thermotolerant -amylase was purified from Bacillus circulans S31 isolated from soil in Hong Kong. The purified enzyme has an M _r of 64 kDa and was stable at 50°C and pH 7.0 for 30 min. Its K _m for starch was 0.9 mg/ml with a V _max of 0.3 mg/min. It was not activated by any metal ion although sulphydrys reagents were inhibitory.H.S. Kwan, K.H. So and K.Y. Chan are with the Department of Biology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong S.C. Cheng is with the Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic, Hung Hom, Hong Kong.     

Phylogenetic relationships in the harmful dinoflagellate Cochlodinium polykrikoides (Gymnodiniales, Dinophyceae) inferred from LSU rDNA sequences

Phylogenetic relationships among chain-forming Cochlodinium species, including the harmful red tide forming dinoflagellate Cochlodinium polykrikoides, were investigated using specimens collected from coastal waters of Canada, Hong Kong, Japan, Korea, Malaysia, México, Philippines, Puerto Rico, and USA. The phylogenetic tree inferred from partial (D1–D6 regions) large subunit ribosomal RNA gene (LSU rDNA) sequences clearly differentiated between C. polykrikoides and a recently described species, Cochlodinium fulvescens. Two samples collected from the Pacific coasts of North America (British Columbia, Canada and California, USA) having typical morphological characters of C. fulvescens such as the sulcus located in the intermediate region of the cingulum, were closely related to C. fulvescens from western Japan in the phylogenetic tree. Cochlodinium polykrikoides formed a monophyletic group positioned as a sister group of the C. fulvescens clade with three well-supported sub-clades. These three clades were composed of (1) East Asian, including specimens collected from Hong Kong, western Japan, and southern Korea, (2) Philippines, from Manila Bay, Philippines and Omura Bay, Japan, and (3) American/Malaysian, from the Atlantic coasts of USA, the Pacific coast of México, Puerto Rico, and Borneo Island, Malaysia. Each of these clades is considered to be a so-called “ribotype” representing the population inhabiting each region, which is distinguished based on ribosomal RNA gene sequences in the species despite similarities in their morphological characters.     

The reproductive biology of <Emphasis Type="Italic">Nassarius festivus</Emphasis> (Powys, 1835) (Gastropoda: Nassariidae) in relation to seasonal changes in temperature and salinity in subtropical Hong Kong

The reproduction of Nassarius festivus (Gastropoda: Nassariidae) has been studied on three contrasting beaches in Hong Kong. There was no significant difference in shell heights between females and males of N. festivus at three study sites and the sex ratio was always female biased. The highest female sex ratio was recorded from Starfish Bay, followed by Tai Tam Bay and then Tai Mong Tsai. The sexual cycle of N. festivus is completed in 1 year in Hong Kong. It is a winter spawner with a reproductive period ranging from September to May. The gonads progressively mature in autumn with maturity being achieved in winter. Spring and summer are times of gonadal decline and gametogenesis initiation, respectively. The ranges in water temperature and salinity at which mature individuals occur were 13.7–28.0°C and 19.3–29.0‰, respectively. N. festivus produces between 16 and 46 eggs·capsule⁻¹. Over its short life span of 1.21 years, therefore, N. festivus attempts to maximize reproductive output. The eggs hatch as veligers which remain in the plankton for between 33 and 41 days. In terms of its reproductive biology, it is concluded that N. festivus behaves as a typical sub-tropical species with a mix of tropical and temperate characteristics seen in other nassariids from these latitudes.     

Lignocellulolytic enzyme profiles of edible mushroom fungi

One of the most economically-viable processes for the bioconversion of many types of lignocellulosic wastes is represented by edible mushroom cultivation. Lentinula edodes, Volvariella volvacea and Pleurotus sajor-caju are three important commercially cultivated mushrooms which exhibit varying abilities to utilise different lignocellulosics as growth substrate. Examination of the lignocellulolytic enzyme profiles of the three species show this diversity to be reflected in qualitative variations in the major enzymic determinants (i.e. cellulases, ligninases) required for substrate bioconversion. For example, L. edodes, which is cultivated on highly lignified substrates such as wood or sawdust, produces two extracellular enzymes which have been associated with lignin depolymerisation in other fungi, (manganese peroxidase and laccase). Conversely, V. volvacea, which prefers high cellulose-, low lignin-containing substrates produces a family of cellulolytic enzymes including at least five endoglucanases, five cellobiohydrolases and two -glucosidases, but none of the recognised lignin-degrading enzymes.J.A. Buswell, Y.J. Cai, S.T. Chang, J.F. Peberdy and S.Y. Fu are with the Department of Biology, The Chinese University of Hong Kong, Shatin, Hong Kong. J.A. Buswell and S.T. Chang are also with the Centre for International Services to Mushroom Biotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong. J.F. Peberdy is also with the Department of Life Science, University of Nottingham, United Kingdom. S.Y. Fu is also with, and H.-s. Yu is with the Institute of Chemistry, Academia Sinica, Guangzhou, China.     

Isolation and characterization of restriction endonuclease EclHKI from an Enterobacter cloacae strain

An Enterobacter cloacae strain, producing restriction enzyme EclHKI, was isolated from a decaying potato. The enzyme is an isoschizomer of Eam1105I, which recognizes and cleaves GACNNN!NNGTC. EclHKI was produced at high activity (4×10⁴ U/g wet cells) and was purified from contaminants which interfere with restriction digestion by passing the cell lysate through DEAE-Sephacel and heparin columns. Activity was optimal at 37°C in a medium salt buffer.H.-Y. Chan, Y.-C. Chan and P.-C. Shaw are with the Department of Biochemistry, The Chinese University of Hong Kong, Hong Kong: K.-M. Kam is with the Institute of Pathology, Sai Ying Pun Jockey Club Clinic, Hong Kong.     

Molecular Coordinated Regulation of Gene Expression During Ovarian Development in the Penaeid Shrimp

To understand the molecular events of ovarian development in penaeid shrimp, RNA arbitrarily primed polymerase chain reaction (RAP-PCR) was used to identify differentially expressed genes during ovarian maturation in Metapenaeus ensis. From a screening of 700 clones in a cDNA library of the shrimp ovary by the products of RAP-PCR of different maturation stages, 91 fragments with differentially expressed pattern as revealed by dot-blot hybridization were isolated and sequenced. Forty-two of these fragments show significant sequence similarity to known gene products and the differentially expressed pattern of 10 putative genes were further characterized via Northern hybridization. Putative glyceraldehyde–3–phosphate dehydrogenase and arginine kinase are related to provision of energy for active cellular function in oocyte development. Translationally controlled tumor protein, actin, and keratin are related to the organization of cytoskeleton to accomplish growth and development of oocytes. High mobility group protein DSP1, heat shock protein 70, and nucleoside diphosphate kinase may act as repressors before the onset of ovarian maturation. Peptidyl-prolyl cis-trans isomerase and glutathione peroxidase are related to the stabilization of proteins and oocytes. This study provides new insights on the molecular events in the ovarian development in the shrimp. Present addresses: T.S. Lo, Department of Applied Science, Hong Kong Institute of Vocational Education, Chai Wan, Hong Kong, China J.L.Y. Mong, Department of Biochemistry, The Chinese University of Hong Kong, Shatin, Hong Kong, China Q.W.L. Wong, Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong, China     

Distribution of toxigenic Bacillus cereus in rice samples marketed in Hong Kong

Eleven of 16 samples of rice on sale in rice shops and supermarkets in Hong Kong contained Bacillus cereus. Although B. cereus counts did not exceed 100 bacteria/g in most of the positive samples, a sample of Thai red rice and a poor quality rice originating from China contained between 300 to 1000 cells/g and 10⁴ to 2×10⁵ cells/g, respectively. Nine strains produced an enterotoxin responsible for the diarrhoeal-type B. cereus food poisoning and seven of these strains also produced a haemolysin (haemolysin BL), a dermonecrotic vascular permeability factor which may be a virulence determinant in diarrhoeal illness caused by this bacterium.P.K. Lee and J.A. Buswell are with the Department of Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong; K. Shinagawa is with the Department of Veterinary Medicine, Iwate University, Iwate, Japan.