凝胶电泳与共头霉分类

对于共头霉的唯一已知种总状共头霉Syncephalastrum racemosum Cohn ex Schroet.(S 1)和新发现的具单孢孢子囊的新种单孢共头霉下的三个变种,原变种S.monosporum Zheng et al. var. monosporum( S7, S8, S9),冠囊变种var. cristatum Zheng et al. (S10, S11)及多重生变种var. pluriproliferum Zheng et al.(S12) 6株菌的蛋白和酯酶进行了聚丙烯酰胺凝胶电泳的研究.这4个分类群的蛋白图谱和酯酶酶谱互不相同,而同一分类群内各个菌株之间则有很高的相似性.从计算出的相似性百分数来看,3个新变种相互之间有较为密切的关系,而和S. racemosum虽然较疏远,但也有相当程度的亲缘关系.这些结果被认为支持了根据形态鉴定而定这三个新变种属于同一新种内并将其和S. racemosum一并归属于一个属内.由此可见,聚丙烯酰胺凝胶电泳是共头霉分类的有用的辅助手段.     

马尔尼菲青霉的分类学研讨

马尔尼菲青霉能引起人和鼠类的马尔尼菲青霉病,1956年由Capponi等分离自越南的竹鼠,后由Segretain (1959)正式发表为新种.DiSalvo等(1973)首次报道此菌对人的自然感染,也分离了菌种。Pitt (1980'1979')承认Segretain的菌株为马尔尼菲青霉,但把DiSalvo的菌株(ATCC 24100)由于具明显的黄色菌丝而与岐生青霉金黄色变种(ATCC 10438)合并,成立了樱草黄青霉新种。近年来一些中国的研究者对广西的竹鼠作了大量的调查,证明竹鼠普遍携带此菌,并分离了大量菌株。作者对来自广西的34株分离物(2株来自患者,32株来自银星竹鼠)根据形态和培养特征作了鉴定,并用IMI 68794(来自模式),ATCC 24100和ATCC 10438作了对比。全部34株分离物尽管在菌落外观有明显不同(许多菌株产生黄色具饰菌丝,影响菌落外观)但根据其帚状枝及瓶梗的特征,产生紫红色素以及在370C形成酵母状细胞诸特点,作者认为都是马尔尼菲青霉。ATCC 24100也同样具有马尔尼菲青霉的特征。而ATCC 10438虽然也产生明显的黄色菌丝,但其帚状枝和瓶梗与马尔尼菲青霉不同,不产生紫红色素,在370C不生长,因此不是同一个种。ATCC 24100应保持原来的种名马尔尼菲青霉。     

蛋白和酯酶电泳在根霉鉴定上的应用

对根霉(Rhizopus)属的十个种或变种共二十四株菌的菌体可溶性蛋白和酯酶同工酶进行了电泳的研究得到对这个属分类上更多的依据.在严格控制培养,提取和电泳条件的情况下,同一株菌不同批次所得菌体蛋白电泳图谱有较好的重复性.在相同的条件下,每个种的根霉有各自特征性蛋白图谱,种内不同菌株的蛋白图谱和酯酶酶谱基本相同.特别是形态特征明显、分类地位明确的种,种内各株的图谱也较一致,如R. stolonifer;与R.circinans.在确定新变种R. delemar var. latoapicalis时,电泳图谱与R.delemar var.delema:有明显不同,起到了佐证作用.因此认为,蛋白图谱与酯酶酶谱相辅相成,在根霉种的分类中是一有效的辅助手段.     

中国菱属(菱科)植物的分类研究

菱科(Trapaceae)仅菱属(Trapa L.)1属,该属是典型的水生多型植物,中国乃至全球以往的分类处理分歧很大。基于文献查阅、野外采集、标本鉴定和栽培观察,对菱属植物分类的主要形态性状作了系统评价。果体大小和果冠变异稳定,可以用于属内种的划分,果喙大小和角的数目则可以用于种下变种的划分。在此基础上,对中国菱属作了分类处理,承认了细果野菱(T. incisa)和欧菱(T. natans)2个种,并将欧菱划分为6个变种,对其中4个变种作了新的组合。将10个种名和12个变种名处理为异名,并对5个名称(Trapa amurensis,T. bispinosa,T. dimorphocarpa,T. japonica,T. manchurica)作了后选模式标定。     

共头霉的单孢孢子囊变种

我们从江苏、浙江两省采到的一些样品中分离得到六株毛霉菌种并鉴定为分别属于三个变种的同一个新种,即单孢共头霉原变种(Syncephalastrum monosporum Zheng et al.sp. nov. var. monosporum),单孢共头霉冠囊变种(Syncephalastrum monosporum Zheng et al. var. cristatum Zheng et al. var. nov.),以及单孢共头霉多重生变种(Syncephalastrum monosporum Zheng et al. var. pluriproliferum Zheng et al. var. nov.).它们与共头霉属的唯一已知种总状共头霉(Syncephalastrum racemosum Cohn ex Schroeter)的主要区别在于全部孢子囊都是单孢的小型孢子囊(柱孢囊)而不是像后者一样孢子成单行排列的多袍柱孢囊.我们把这些菌归人共头霉属而没有为它们专门成立一个新属的理由除因它们与总状共头霉有明显的亲缘关系外,主要还因我们认为在不具备其它重要区别特征的情况下,在毛霉目的分类中,无论在科级或属级的水平上,都不应过分强调单孢孢子囊的作用.尽管单孢共头霉是毛霉目内唯一具单孢子柱孢囊的种,我们仍然把它们归入共头霉属内.至于我们为什么要把这六株菌鉴定为一个种的三个变种而不是三个各自独立的种,则是由于我们承认共头霉属的唯一已知种总状共头霉是一个变异性很大的种而并没有把它分成许多不同的种,因此,我们对这个属的另外一个种,即单孢共头霉同样采用较大的种概念.     

刺孢小克银汉霉原变种和轮生刺孢小克银汉霉变种(新组合)

刺孢小克银汉霉[Cunninghamella echinulata(Thaxt.) Thaxt. ex Blakeslce]是小克银汉霉属的模式种,多年来因不同作者是否将贝尼尔小克银汉霉(C. bainieri Naum.)包含在内而对此种持广义(sensu lato)或狭义(scnsu stricto)的不同理解。我们在国内分离到51株刺孢小克银汉霉(广义)菌种,经与获自css的7株菌(包括刺孢小克银汉霉的模式菌种在内)和IMI的1株菌(原定名称均为刺孢小克银汉霉)一起研究后,根据它们的无性型形态特征有明显不同但在配合试验中又可互相配合形成可育的接合孢子的结果,认为将它们处理为同一个种的两个不同变种较为合理.其中,13株中国的菌和3株CBS及IMI的菌被鉴定为刺孢小克银汉霉原变种(C. echinulata var. echinulata);其余的38株中国的菌和5株CBS的菌被鉴定为轮生刺孢小克银汉霉变种(新组合)[C. echinulata var. verticillata (F. S. Paine.) comb. nov.j.以‘轮生(verticillata)’作为新组合变种的加词是根据与贝尼尔小克银汉霉同物异名的‘轮生布拉小克银汉霉(C. blakesleeana var. verticillata (F. S. Paine) Baijal & B. S. Mchrotra)’而来的.在前人的工作中,对刺孢小克银汉霉持狭义理解的作者往往根据孢子枝的分枝方式、巨型暗色孢子的有无、以及40℃能否生长来区分这两个分类群.对刺孢小克银汉霉持广义理解的作者则认为这些特性毫无意义.我们同意后面两个特性意义不大,因为二者的许多菌系都能形成巨型暗色袍子并在40℃生长,但认为孢子枝分枝方式确实是区别这两个分类群的重要依据.此外,根据产孢构造的种类、孢子枝主枝的直径、孢子枝第一次分枝的数目、分枝长度、孢子枝主枝的顶生泡囊形状以及其直径等性状综合考虑,这两个分类群是不难明确区分的,对12株刺孢小克银汉霉原变种和13株轮生刺孢小克银汉霉相互之间所进行的配合试验结果表明,在具一定性亲和力的(+)、(一)菌系同时存在时,两个变种内和变种之间均可形成可育的接合孢子。对上述三种配合的各六对菌所形成的有性型形态的研究结果则表明,除轮生刺孢小克银汉霉变种内形成的接合孢子的壁往往较厚外,各种配合形成的有性型形态基本上是一致的.我们研究组的其他成员最近曾对小克银汉霉的22株菌进行了rDNA的ITS区的PCR产物长度测定,其中包括了刺孢小克银汉霉原变种和轮生刺孢小克银汉霉变种的各3株菌,它们的平均长度(bp)分别为890±7.5和915±7.6.这个结果也支持了我们在这两个分类群可以互相配合的情况下仍将它们作为两个不同变种的处理.这两个分类群虽然已被发表多次,但它们的描述和绘图均过于简单而未能充分显示出它们的区别性特征,因此我们在本文中再次作了描述并再次提供了详尽的线条图和显微照相.     

青霉属的三个新种

本文报导青霉属的三个新种,它们不同于此属已发表的诸种.异型青霉(Penicillium heteromorphum Kong et Qi),根据帚状枝的结构和分生孢子的某些特征,近于两型孢青霉(Penicillium dimorphosporum Swart),但此种在查氏琼脂上生长很稀疏,并有两种大小的分生孢子,大分生孢子直径可达10 pm,壁光滑,在观察菌落期间,有时大分生孢子落在基质上,很快萌发生长成简单的分生孢子结构,这些特征易于与后者区分.结节青霉(Penicillium nodulum Kong et Qi)在某些方面类似纠缠青霉(Penicilliumimplicatum Biourge),此新种的菌落特征,柄顶端膨大似顶囊,呈结节状膨大的营养菌丝等特征而不同于纠缠青霉.神农架青霉(Penicillium shennong jianum Kong et Qi)和毡毛青霉(Penicillium velutinum van Heyma)相近,而新种在多种培养基上生长都局限,菌落面呈带褐的橄榄色,分生孢子壁光滑等特征可与毡毛青霉区分开来.     

广西金花茶新植物(二)

作者原先对该植物的分类研究结果已确认为一新种,但经《植物分类学报》送有关专家审查后,降为金花茶Camellia chrysantha (Hu) Tuyuma的变种发表。及后,有的学者又把它视为与原变种无异而予以归并。作者曾一再对该植物作了较多的观察,对比研究,觉得其主要特征与金花茶的差异是相当明显的,不但花小,果小,而且花瓣开放时近平展,萼片及花瓣内面均被柔毛,边缘具流苏状小缘毛,这些特征是比较稳定的,而在金花茶是不存在的。同时其染色体组型亦有差异,因此,作者认为把它视为金花茶的一个变种也不适当,把它与金花茶视为一物更不客观,以提升为种较适宜。     

小毛茛居群的遗传分化及其与空间隔离的相关性

采用聚丙烯酰胺凝胶电泳技术,对分布于华中地区的11个小毛茛（Ranunculus ternatus）居群的遗传分化进行了检测。对8个酶系统17个酶位点上的分析结果表明,该种各居群 的各项遗传多样性指标处于一个相对较低的水平：多态位点比率（P）为0～53.0%,平均每位点等位基因数（A）为1～1.647,平均预期杂合度（H_e）和观察杂合度（H_o）分别为0～0.108和0～0.102。居群间遗传一致度甚高（I＝0.9754～0.9991）。根据Nei′s遗传距离所作出的聚类分析表明,豫南信阳地区3个居群与湖北省武汉地区8 个居群之间关系较远。而在武汉地区,长江以北的居群及长江以南的部分居群分别相聚在一 起。用GPS定位方法得到居群间空间距离并据此聚类,结果显示了该种的遗传分化与地理因 素 的相关性,并推测出长江的隔离作用加强了两岸居群间的遗传分化。同时发现一个生于独特 生境的居群在表型和遗传结构上都已与其他邻近居群有了很大分异,由于该居群在所检测的 酶位点上均无特有等位基因出现,作者认为不宜将其作为新种或新变种处理。     

8个栽培水杉居群遗传多样性的等位酶分析

水杉(Metasequoia glyptostroboides)是我国特有的活化石植物,有50多年的栽培历史。栽培水杉在多大程度上涵盖了野生水杉的遗传多样性,是评价水杉保育策略成功与否的关键所在。为了评估水杉栽培居群的遗传变异水平,作者采用超薄平板微型聚丙烯酰胺等电聚焦电泳方法对水杉的8个人工栽培居群的等位酶变异和遗传多样性进行了研究。对9个酶系统23个酶位点的检测结果表明: 有8个酶位点的等位基因频率分布差异非常显著, 在2个居群中存在稀有等位基因;平均等位基因数Ａ=1.375,多态位点百分率PPL=33.15,平均预期杂合度H_e=0.161。与孑遗居群相比,　栽培水杉的遗传变异水平偏低,表明栽培居群的遗传多样性不能完全涵盖孑遗居群。将采于潜江的9个丛枝水杉（Metasequoia glyptostroboides var.caespitosa）样品与分别采自潜江、武汉和上海的各9个水杉样品的等位酶资料进行了UPGMA单株聚类分析,并将丛枝水杉作为一个居群与其他8个水杉居群作UPGMA聚类分析,其结果不支持将丛枝水杉作为水杉的一个变种的分类处理。     

Genetic differentiation among morphological variants of Acacia saligna (Mimosaceae)

This study investigated the pattern of genetic variation in Acacia saligna (Labill.) H.L. Wendl. to facilitate its development as a crop species for dryland salinity management. A. saligna is a morphologically variable species and four main variants are recognized. The genetic structure within A. saligna was investigated in populations across the geographic range of the species using nuclear restriction fragment length polymorphism loci. The analysis identified considerable genetic variation within A. saligna that was genetically structured into three groups. Two of the three groups corresponded to variants recognized in the field study; the third group encompassed the other two variants which, though morphologically different, were not genetically differentiated. The level of genetic differentiation between the groups suggests they may represent different taxa and a taxonomic revision of the species may be required. Identification of different taxa within A. saligna will have implications for the utilization and domestication of the species, as the taxa will need to be evaluated separately to determine their suitability for agroforestry. The high genetic variation between and within groups suggests there is a large genetic base available for breeding improved cultivars.     

几株类棒束孢菌株分类地位的修订

[背景] 粉棒束孢是自然环境中常见的一种昆虫病原真菌,全球广泛分布且寄主多样。然而,棒束孢属许多种形态学特征相似,仅根据经典形态学鉴定容易出现错乱现象。长期以来依据形态特征鉴定为粉棒束孢的菌株,其准确的分类地位出现了越来越多的争议。最近,该属起源被确定是多系发生的。[目的] 明确粉棒束孢的分类沿革并探究先前被鉴定为粉棒束孢菌株的准确分类地位。[方法] 选取6株先前被鉴定为粉棒束孢的菌株,对其进行经典形态观察,并扩增5个基因位点（nrSSU、nrLSU、TEF、RPB1和RPB2）的基因序列,进行多基因分子系统发育学分析。[结果] 通过查阅文献和实验研究,明确了粉棒束孢分类研究的历史沿革;供试的6株不同来源的菌株与粉棒束孢模式种亲缘关系较远,而与新成立的组合种Samsoniella hepiali完全一致。[结论] 利用经典形态学特征和构建5个基因系统发育树,重新修订6株类棒束孢菌株的正确分类地位为Samsoniella hepiali。为该类昆虫病原真菌正确分类提供合理的方法,也为开发和利用该类菌株提供科学的指导。     

纤维单胞菌属放线菌的研究进展

纤维单胞菌属(Cellulomonas)的一些菌株能够产生多种纤维素酶,在纤维素降解方面显示出明显优势。1923年Bergey等以产黄纤维单胞菌为模式菌建立了纤维单胞菌属。1991年Stackebrand和Prauser又以纤维单胞菌属为模式属建立了纤维单胞菌科(Cellulomonadaceae)。目前,纤维单胞菌属包含有从多种环境中分离培养得到的26个有效描述种。纤维单胞菌属菌株在分类学上的典型特征是:细胞壁的肽聚糖成分主要含有Orn和Glu/Asp,以MK-9(H4)为主要的甲基萘醌,主要的脂肪酸成分为anteiso-C15:0和C16:0,极性脂成分主要包括双磷脂酰甘油(DPG)和磷脂酰肌醇甘露糖甙(PIM)。基因组DNA的G+C含量为(68.5–76.0)mol%。最近,本实验室分离到2株纤维单胞菌,应用多相分类研究手段确定了他们的分类学地位。本文将结合我们的研究,对纤维单胞菌属的建立、分类学特征及其在生态和酶资源应用方面进行综述。     

A revision of the genus <Emphasis Type="Italic">Podococcus</Emphasis> (<Emphasis Type="Italic">Arecaceae</Emphasis>)

Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed     

Phylogenetics and the conservation of rare taxa in the Eucalyptus angustissima complex in Western Australia

Effective conservation that preservesevolutionary entities and processes requiresconservation action that is targeted atappropriate taxonomic units. Molecularphylogenetics can contribute to the resolutionof taxonomic uncertainties by defining therelationships between populations and species,and allowing the recognition of taxonomicentities that reflect evolutionary history.Some uncertainty surrounds the status of taxain the Eucalyptus angustissima complex,which includes threatened taxa with restricteddistributions. The phylogenetic relationshipsbetween populations and taxa in the E.angustissima complex were investigated usingnuclear and chloroplast RFLP analysis.Phylogenetic relationships confirmed thegenetic differentiation of two taxa, identifiedspecies level divergence between two taxacurrently recognised at subspecies level, andestablished the identity of a previouslyundetermined population. Phylogeneticrelationships between the taxa were notcongruent with presumed relationships based onmorphological characters alone.     

Genetic variation in two sympatric European populations of Bosmina spp. (Cladocera) tested with RAPD markers

We used RAPDs (Random Amplified Polymorphic DNA) to test genetic divergence between two populations of Bosmina spp. in Lake Östersjön, Sweden. Previous taxonomic studies on European species within the genus Bosmina have been based on morphological characters alone. RAPD markers distinguished the two populations and supported the specific status of B. coregoni and B. longispina based on morphological characters. Furthermore, juveniles with a long antennule and a mucro were classified as B. coregoni. RAPDs also revealed genetic differences among the tested individuals, suggesting several clones within each species.     

A reassessment of the taxonomic and phylogenetic affinities of the fossil catarrhines from fort Ternan,Kenya

This paper presents a reassessment of the taxonomic and phylogenetic affinities of the fossil catarrhine primates from the important middle Miocene site of Fort Ternan in Kenya. Although the sample of specimens is rather small, the material can be attributed to at least five different species, identified here asKenyapithecus wickeri, Proconsul sp., a large species of oreopithecid,Simiolus sp., and a small species of catarrhine of indeterminate status.Kenyapithecus wickeri probably represents a conservative sister-taxon of the extant large hominoids. It is more derived than“Sivapithecus” africanus from Maboko Island, from which it can be distinguished at the generic level. A small species of catarrhine from Fort Ternan can be attributed toSimiolus. It is probably a different species fromSimiolus enjiessi from the early Miocene of East Africa, but additional material is needed to confirm its taxonomic distinctiveness. The occurrence of at least five species of catarrhine primates at Fort Ternan confirms that species diversity levels were as high during the middle Miocene as they had been during the early Miocene. However, the overall taxonomic and ecological composition of the middle Miocene catarrhine community was quite different, evidently due to a significant change in the local ecological setting. Taxonomic differences between the catarrhine faunas at Fort Ternan and Maboko Island can probably be explained as a consequence of a chronological separation between the two sites, and, to a lesser degree, to paleoecological differences.     

Genetic nature of eastern wolves: Past, present and future

Eastern North American wolves have long been recognized as morphologically distinct from both coyotes and gray wolves. This has led to questions regarding their origins and taxonomic status. Eastern wolves are mainly viewed as: (1) a smaller subspecies of gray wolf (Canis lupus lycaon), potentially the result of historical hybridization between gray wolves (C. lupus) and red wolves (C. rufus), (2) a hybrid, the result of gray wolf (C. lupus) and coyote (C. latrans) interbreeding, or (3) a distinct species, C. lycaon, closely related to the red wolf (C. rufus). Although debate persists, recent molecular studies suggest that the eastern wolf is not a gray wolf subspecies, nor the result of gray wolf/coyote hybridization. Eastern wolves were more likely a distinct species, C. lycaon, prior to the eastward spread of coyotes in the late 1800s. However, contemporary interbreeding exits between C. lycaon to both C. lupus and C. latrans over much of its present range complicating its present taxonomic characterization. While hybridization may be reducing the taxonomic distinctiveness of C. lycaon, it should not necessarily be viewed as negative influence. Hybridization may be enhancing the adaptive potential of eastern wolves, allowing them to more effectively exploit available resources in rapidly changing environments.     

Morphological analysis ofAlouatta seniculus species group (Primates,Cebidae). A comparison with biochemical and karyological data

Fifteen cranial measurements were taken from wild caught specimens ofAlouatta seniculus seniculus, A. s. stramineus andA. s. macconnelli. A morphological analysis showed sex dimorphism in these three groups. A multivariate analysis discriminated among these taxa; males being more clearly discriminated than females. Our data showed that these taxa can be separated on the basis of quantitative cranial traits, biogeographic distribution, karyological differences, and biochemical characters. We therefore propose a new taxonomic arrangement, changing their taxonomic status to the species level (Alouatta seniculus, A. macconnelli, andA. stramineus).