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1.
Three species, Triplaris dugandii Brandbyge, T. moyobambensis Brandbyge, and T. physocalyx Brandbyge, all from lowland Amazonian South America are described as new to science.  相似文献   

2.
A revision of the generic limits between Triplaris and Ruprechtia (Polygonaceae), which were confused in earlier literature, led to the conclusion that the two genera should be maintained. Triplaris is characterized by 1–flowered pistillate partial inflorescences, absence of a basal pedicel–like extension of the fruiting perianth–tube, which is always as long as or longer than the achene, bracteoles completely fissured on the abaxial side, and sessile or subsessile male flowers with perianth segments always connate for more than half of their length.
Ruprechtia has 2–3–flowered monochasial pistillate part–inflorescences (except the 1–flowered R. triflora) , a basal pedicel–like extension of the fruiting perianth–tube, which is at most 3/4 as long as the achene, more or less tubular bracteoles only exceptionally fissured down on the abaxial side, and pedicellate male flowers with perianth segments never connate for more than one third of their lenght. Preliminary paly–nological studies have shown that the pollen of Triplaris are microreticulate or punc–tate–microreticulate while Ruprechtia pollen have perforate–rugulose surfaces.  相似文献   

3.
Three new species, Ruprechtia maracaensis, Ruprechtia nitida , and Triplaris matogrossensis are described. Ruprechtia glauca is a poorly known species from the state of Bahia. Its relationship with R. laxiflora is discussed.  相似文献   

4.
金线草的系统位置一直存在争议,该试验以Triplaris weigeltiana为外类群,采用最大简约法对金线草及其近缘类群的ITS序列进行了系统发育分析.结果表明:(1)金线草和蓼属的春蓼组、刺蓼组形成三个并列的分支,因此,金线草没有必要独立成属,分子证据支持金线草成立为组;(2)金线草和春蓼组、刺蓼组植物聚在一起,...  相似文献   

5.
6.
New species ofCoccoloba are described from Mexico (Coccoloba ortizii), Honduras (Coccoloba cholutecensis), Panama (Coccoloba gentryi andC. johnstonii), Venezuela (Coccoloba yaracuyensis), and Brazil (Coccoloba bullata). Recent collections have permitted the re-examination of species from Central and South America.Coccoloba escuintlensis Lundell,C. floribunda (Bentham) Lindau, andC. williamsii Standley, which had been placed in synonymy, are now re-established. The following species have been placed in synonymy after the examination of additional collections:Coccoloba itzana Lundell,C. matudai Lundell,C. oligocarpa Lundell,C. petensis Lundell,C. tenuis Lundell,C. verapazensis Lundell,C. viridis Lundell,C. ecuadorensis Brandbyge,C. trollii Brandbyge andC. inaequilatera Rizzini.  相似文献   

7.
The relationship between the myrmecophytic tree Duroia hirsuta (Rubiaceae) and its associated, minute, non-aggressive Myrmelachista sp. (Formicinae) ants is poorly investigated, even though the small understory tree is surrounded by a conspicuos zone almost devoid of vegetation. As to the cause of these barely vegetated "Devil's Gardens", two alternative interpretations exist in the literature: the pruning activity of ants and allelopathy. We investigated the mutualistic Duroia-Myrmelachista system in the Ecuadorian Amazon, focusing on the phenomenon of the areas of reduced vegetation, as well as on the natural history of the associated ants. We conducted planting experiments and behavioral studies, including coccoids, the third partner in this mutualism. Because the well-studied Triplaris americana (Polygonaceae) possesses analogous vegetation free surroundings created by the assiduous mechanical pruning of its mutualistic ant partner (Pseudomyrmex sp.), parallel comparative investigations of this ant-plant association were conducted. The two systems are not equivalent; it was demonstrated that the remarkably inactive Myrmelachista ants are not responsible for the bare areas around Duroia plants. Instead, we regard allelopathy as the causative agent for the clear zones.  相似文献   

8.
The Neotropical ant Pseudomyrmex triplarinus is involved in an obligate and complex symbiotic association with Triplaris americana trees. The ants inhabit trunk and branch domatia and respond aggressively to foreign invaders. Their degree of host specificity and basis for recognition of host trees has not been studied. We determined that, in contrast to T. americana seedlings, heterospecific seedlings set around the host trees suffered continuous pruning. Ants also removed 80–100 percent of heterospecific leaves attached to the trunk in contrast to only 10–30 percent of conspecific leaves. True species specificity was demonstrated by the selective removal of leaves from Triplaris poeppigiana pinned to host trees. This selectivity was also observed in a matrix‐independent bioassay using leaf cuticular extracts on glass microfiber strips. Strips treated with leaf wax extracts from host trees and pinned to the trunk of host trees received only 42 percent of the number of ant visits recorded on solvent‐treated controls by the end of the experiment. Strips treated with extracts of a related species, T. poeppigiana, received 64 percent of the number of ant visits compared with solvent‐treated controls. These experiments also suggest that P. triplarinus recognizes surface chemicals of their host tree, independent of the texture or architecture of the carrier material; although these factors may still play some role in recognition. This is the first study that we are aware of to investigate the mechanism of host discrimination related to pruning behavior. Abstract in Spanish is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   

9.
孙必兴  王松 《植物研究》1990,10(4):13-20
在禾本科植物编志工作中,我们先后订正了一些族、属和种的分类学问题,发现了不少新植物和一些在我国境内首次记录的种。本文只报道云南虉草族的各分类群,包括茅香属1种,黄花茅属4种1变种,其中1个是新种,1个是新变种,1种是中国新记录,虉草属3种及1变种,其中2种是中国新记录。  相似文献   

10.
A phytosociological study was conducted in a riparian forest of the Rio Paraguai near Corumbá and Ladário in the state of Mato Grosso do Sul, Brazil. The topographic distribution of species was correlated with durations of the river's seasonal floodings and the cumulative time of flooding between 1974 and 1995. One hundred and eight contiguous 10×10 m plots were systematically established. All individuals with more than 15 cm of girth at breast height (gbh=1.3 m) were sampled. A total of 695 individuals distributed among 37 species, 35 genera and 23 families were found. The Shannon index (H′) for species diversity was 2.7. The highest importance value (IV) was found for Inga vera ssp. affinis, followed by Triplaris gardneriana, Ocotea diospyrifolia, Crataeva tapia and Vochysia divergens. The plots were classified into two groups according to their distance from the margin, applying Ward's method of classification and principal coordinate analysis (PCO) on the same Bray Curtis distance matrix. The topical environments were divided into four bands by Two-Way Indicator Species Analysis (TWINSPAN), and the species were also grouped into four groups. Flooding in these groups ranged from regular inundation in all 23 years of the historical series of the Ladário gauge to sporadic flooding for a maximum of 2 consecutive years.  相似文献   

11.
报道了白粉菌目的一个新变种和一个中国新记录种。新变种:苋生蒙加拉白粉菌Erysiphemunjalii var.amaranthicola,寄生在苋科皱果苋Amaranthus viridis上;新记录种:山田叉丝壳Microsphaera yamadai,寄生在鼠李科拐枣Hovenia dulcis上。新变种有中文和拉丁文描述。研究标本保存在中国科学院微生物研究所菌物标本馆(HMAS)。  相似文献   

12.
中国葡萄属(Vitis L.)的系统研究   总被引:8,自引:0,他引:8  
对中国葡萄属(Vitis L.)的系统学进行处理。中国葡萄属共分42种1亚种12变种,归属于1亚属5组4系。文中命名了3新组(小叶葡萄组、秋葡萄组和武汉葡萄组)、2新等级及组合组(毛葡萄组和河岸葡萄组)、3新系(密柔毛系、复叶系、刺状毛系)、1新变种(伏牛山葡萄)和1新组合变种(小叶葛Lai)。  相似文献   

13.
郭正堂 《植物研究》1986,6(4):73-92
本文报道中国韧革菌科(Stereaceae Pilat)真菌10种和1变种,隶属于淀粉韧革菌属(Amylostereum Boidin)、北方韧革菌属(Boreostereum Parmasto)、小韧革菌属(Chodrostereum Pouzar)、柱囊韧革菌属(Columnocystis Pouzar)、杯革菌属(Cotylidia Karsten)和皱革菌属(Cymatoderma Junghuhn)。其中有1个新种和1个新记录变种,即海南皱革菌(Cymatoderma hainanense Z.T.Guo,sp.nov.)和黄杯革菌白色变种(Cotylidia aurantiaca(Pers.)Welden var.alba Reid)。标本全部保藏于中国科学院微生物研究所真菌标本室(HMAS)中。  相似文献   

14.
广东楝科植物分类的初步研究   总被引:4,自引:0,他引:4  
本文是对广东楝科植物种类的初步整理、研究,记载了16属33种7交种,包括本省产的13属27种7变种和外来引种的3属6种。其中有1个新变种(封开地黄连Munronia hainanensis How et T. Chen var. microphyllina X. M. Chen),3个新组合(曾椤Amoora tsangii (Merr.) X. M. Chen, 雷楝Reinwardtiodendron dubium (Merr.) X. M. Chen, 毛香椿Toona sinensis (A. Juss.) M. J. Roem. var. schensiana (C. DC.) X. M. Chen), 3个分布新记录[雷楝属Reinwardtiodendron (我国新记录),鹧鸪花Trichilia connaroides (W. et A.) Bentv. var. connaroides(广东新记录),海南(木坚)木Dysoxylvm hainanense Merr. var. hainanense(广东大陆新记录)].  相似文献   

15.
本文报道黑蛋巢菌属Cyathus Haller:Pers.一新种——潞西黑蛋巢Cyathus luxiensis T.X.Zhou,J.Yu et Y.H.Chen,一新变种——非洲黑蛋巢宽孢变种Cyathus africanus H.J.Brodie var.latisporus Y.H.Chen et J.Yu 和一新记录型——壶黑蛋巢布诺德变型Cyathus olla (Batch) Pers .f. brodiensis Shinners et Tewari。给出了每个分类单元的宏观、微观特征图。新种、新变种的模式标本保存于西南林学院真菌标本室(MHSFC)。  相似文献   

16.
A new variety of Ligusticum L. (Umbelliferae), L. sinense var. hupehense collected from Hubei province, is described in this paper.. Cytological investigation shows that the new plant is a diploid, with the karyotypic formula 2n=22=14m+ 8sm. The parameters of chromosomes and the idiogram are given. The comparison of ARC (arm ratio curve) diagram between the new variety andL. sinense is also given.  相似文献   

17.
The alpha-Gal epitope (Gal-alpha1-3Gal-beta1-4-GlcNAc-R), which is biosynthesized by the UDP-Gal:alpha1-3-galactosyltransferase (alpha1, 3GT), is highly associated with hyperacute rejection in swine to human xenotransplantation. A variety of strategies have been pursued to reduce or eliminate this epitope from swine tissues. Since swine ES cells are not available at present, the targeted knock out of the alpha1,3GT is restricted. Other strategies, such as enzyme competition of the alpha1,3GT with other glycosyltransferases and/or control of sugar processing by the glycosyltransferases, provide a new insight into the downregulation of the alpha-Gal epitope. This review will focus on this type of strategy, which involves a gene transfection of variety of glycosyltransferases as competitors against alpha1,3GT.  相似文献   

18.
浙江蔷薇科新分类群   总被引:1,自引:0,他引:1  
描述了浙江蔷薇科1新亚种和1新变种,并分别附有线条图。它们是:腺瓣蔷薇(新亚种)和遂昌红腺悬钩子(新变种)。腺瓣蔷薇与模式亚种单花合柱蔷薇区别在托叶、叶柄和萼片仅密被短柔毛而无腺毛,小叶片较大,两面近无毛或疏被短柔毛,伞房花序具1~3花,花瓣宽倒卵形。遂昌红腺悬钩子与模式变种红腺悬钩子区别在于花梗、小枝和老枝密被腺毛而无柔毛,小叶片两面具腺毛,萼片较长,长13~15mm,先端长尾尖。  相似文献   

19.
报道弯孢属一新名称厚隔弯孢Curvulariacrassiseptum和生于莴苣LactucasativaL.上的一新变种厚隔弯孢莴苣变种Curvulariacrassiseptumvar.lactucae。模式标本保藏于山东农业大学植物病理标本室(HSAUP)。  相似文献   

20.
报道了一个黏菌新变种,小筛菌大孢变种Cribraria microcarpa var.megaspora nov.var.,获得于湿室培养的采自云南大围山国家级自然保护区的柳杉Cryptomeria fortunei树皮上,其特征是比原变种具有明显较大的孢子。这里描述和图示了这个新变种,模式标本保存于南京师范大学微生物菌种保藏中心。  相似文献   

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