中国红豆属植物的叶表皮形态学

用光学显微镜和扫描电子显微镜观察了红豆属(Ormosia)35种的叶表皮形态,这些植物的叶上下表皮细胞为不规则形或多边形,垂周壁有平直、弓形、浅波状或深波状,表皮细胞形状和垂周壁在种间有一些差异。气孔仅存在于下表皮,形状为椭圆形或卵形,以平列型为主;此外还有其他类型的气孔,如长脐红豆、海南红豆等的气孔为不规则形、不等型;少数种类如亮毛红豆、茸荚红豆等的气孔不明显。气孔外拱盖光滑,呈浅波状、波状或不明显,气孔内拱盖光滑、近光滑、浅波状或不明显;蜡被近光滑、颗粒状、鳞片状、条纹状或结网状;多数种具毛被。叶表皮与气孔器特征可作为区分种、变种或亚种的依据。叶表皮微观形态特征支持红豆属成为一个自然类群。     

Two new species of Ophiocaryon (Sabiaceae) from South America

Ophiocaryon barnebyanum from the Serra da Neblina (Venezuelan-Brazilian border) andO. neillii from southern Ecuador are described and illustrated, and their morphological relationships with allied spcies are discussed.Ophiocaryon barnebyanum is morphologically similar toO. duckei, but it differs by its larger leaves, leaflets, petioles, petiolules, and inflorescences, the higher number of secondary veins, and the ciliate sepals.Ophiocaryon neillii is a small tree related toO. klugii but differs by its smaller leaflets, petiolules and inflorescences, fewer secondary veins, lanceolate-acuminate sepals, and orbicular staminodes. An updated key to the species ofOphiocaryon is provided.     

Taxonomic notes on the genus Otoptera (Phaseoleae, Fabaceae) in southern Africa

A taxonomic study of the genus Otoptera (tribe Phaseoleae) is presented. This distinct genus consists of two species, O. burchellii in southern Africa (Namibia, Botswana, South Africa and Zimbabwe) and O. madagascariensis endemic to Madagascar. The two species differ in the shape and size of leaflets, size and orientation of the spur located at the base of the wing petal, and also by size of the pod. A key to the two species is provided. This study focuses mainly on the southern African O. burchellii DC., which is described and illustrated. The species name is lectotypified and the known geographical distribution is recorded for the first time.     

A rare new species of Polhillia (Genisteae,Fabaceae)

The new species Polhillia ignota Boatwr. is described. This species is known only from two collections, one between Vredenburg and Saldanha and the other close to Porterville. The new species is most similar to P. obsoleta, which is known only from a few localities around Worcester, in its narrow, sericeous leaflets and flowers of equal size, but differs in its flattened mature leaves with larger leaflets (up to ± 12 mm long), longer pseudo-peduncles (up to ± 15  mm long), denser inflorescences (with up to four flowers), shorter pedicels (1–2 mm long) and non-auriculate wing- and keel petals.     

Two fungi associated with necrotic leaflets of areca palms (Areca catechu)

Information on fungi associated with necrotic leaflets of exotic palms in Thailand is scanty, as previous studies were mainly focused on decaying fronds. This study provides some information regarding fungi associated with necrotic leaflets of exotic palms in Thailand. Specimens in this work were collected from several locations in Chiang Mai province, including natural and planted areas. One new species, Cercospora arecacearum on areca palm (Areca catechu), is described and illustrated. An ITS sequence data analysis confirms the separation of the new Cercospora species from related taxa. Another species, Neorehmia arecae, hitherto only known from areca palm, is newly recorded for Thailand. Furthermore, Wallichia siamensis is a new host for this species.     

A new species and a new combination in Zanthoxylum (Rutaceae) from Brazil

A new species,Zanthoxylum hamadryadicum, is described, illustrated and compared to its closest relatives. It is unique in its small leaves and leaflets, which are densely stellate-pilose, and its short racemes crowded on new shoots with 4-merous flowers. A new combination,Zanthoxylum hasslerianum (Chodat) Pirani, and some new synonyms among Brazilian species are proposed.     

Enhancement of Phloem Exudation from Fraxinus uhdei Wenz. (Evergreen Ash) using Ethylenediaminetetraacetic Acid

Ethylenediaminetetraacetic acid (EDTA) enhanced the exudation of ¹⁴C-labeled assimilates from excised leaflets and whole plant specimens of Fraxinus uhdei Wenz. A 2 millimolar EDTA concentration was found to be most effective in promoting exudation from excised leaflets, while 10 millimolar EDTA was most effective in whole plants experiments. Exudation rate reached a maximum after 24 hours in both experiments. The continuous presence of EDTA throughout the treatment period was required for maximum exudation from excised leaflets. Stachyose, raffinose, verbascose, and sucrose were the principal compounds found to occur in exudate samples. These compounds are typically transported in sieve elements of various Fraxinus species suggesting the exudate was of phloem origin. Electron microscope studies of petiolule sieve plate pores from excised leaflets showed substantially less callose appearing after treatment with EDTA than after H₂O treatment. It is suggested that EDTA enhances phloem exudation by inhibiting or reducing callose formation in sieve plate pores. The exudation enhancement technique described for whole plant specimens is suggested as a useful means of collecting phloem sap and studying translocation in woody plants.     

Angelica muliensis sp. nov. (Apiaceae) from Sichuan,southwest China

Angelica muliensis (Apiaceae), a new species from Sichuan Province, southwest China, is described and illustrated. The new species resembles A. biserrata, but differs in the shapes of the leaflets and sheaths, umbel number and size and especially mericarp features. The diagnostic characters of these two species are presented and compared.     

Three new species and a revised key to species of Oxalis section Polymorphae (Oxalidaceae)

Three new species of Oxalis sect. Polymorphae are here described and illustrated: Oxalis artemioides, O. calcicola, and O. monochasiata. These species have narrow geographic distributions, each being known from just one location. Oxalis artemioides differs from other species of the section by the glabrous stem, narrow terminal leaflets (8–10.5 × 2 mm), and inflorescences with elongated dichasial branches bearing flowers only in the distal portion. Oxalis calcicola differs from other species by having the young stem with adpressed-retrorse trichomes, inflorescences shorter than adjacent leaves, short dichasial branches (0.5–3 mm long) with flowers densely grouped along the entire length, and glabrous pedicels. Oxalis monochasiata is remarkable because of its monochasial inflorescence and the two-ovulate carpels, both features unique within Oxalis sect. Polymorphae. The new species are compared to similar species of the section, and information on distribution and habitat, phenology, and conservation status according with IUCN criteria are provided. Geographic distribution maps, lists of examined materials and an identification key for species of this section are also presented.     

Four new species of the Didymopanax group of <Emphasis Type="Italic">Schefflera</Emphasis> (Araliaceae) from the Brazilian Amazon

Four new species of the Didymopanax group of Neotropical Schefflera (Araliaceae) from the Brazilian Amazon are here described and illustrated. Two of these are mainly known from the surroundings of Manaus, Amazonas state (Schefflera ciliatifolia and Schefflera umbrosa). The first is distinguished by its ciliate leaflets, while the second is characterized by leaflets varying in shape from trilobed to entire. Schefflera plurifolia is known only from southern Amazonian forests, and is remarkable in its pinnately-compound leaflets. Schefflera dichotoma, only known from the type collected on “campinarana” forests from Upper Rio Negro, at the municipality of São Gabriel da Cachoeira (Amazonas), is characterized by dichotomously branching inflorescences. Comments on the geographic distribution and ecology of the new species are provided, as well as an identification key to the species of the Didymopanax group found in Brazilian Amazonian rainforests and savannas.     

Caesalpinia elliptifolia (Leguminosae: Caesalpinioideae): a new species from China

A new species, Caesalpinia elliptifolia , is described from Guangdong, China. The species is related to C. magnifoliolata and C. crista , but can be easily distinguished by its subsymmetrical pod with a wide cuneate base, brown hairs on the lower surfaces of leaflets, pedicels of flowers and fruits, and axis of inflorescences.     

A new species of Picramnia (Simaroubaceae) from Amazonian Peru

A new and rare species,Picramnia bullata, is described, illustrated, and compared to its closest relatives It is unique in its hirsute pubescence, numerous, elongate, bullate leaflets, and long, pendent, unbranched inflorescences.     

A new species of ceratozamia (Zamiaceae) from Veracruz,Mexico with comments on species relationships,habitats, and vegetative morphology in ceratozamia

Ceratozamia euryphyllidia from Veracruz is described and illustrated. This species differs from all others in the genus in its very large, broad leaflets (9–16 cm wide) which have undulate margins, prominent veins, and a membranous to translucent texture at maturity. It is apparently related to a group of species which all have relatively small strobili and leaflets that are attenuate basally, oblanceolate to obovate, inequilateral, abruptly acuminate apically, and generally papyraceous to membranaceous. The allopatric species of this group inhabit moist to very wet areas. The wetter the habitat, the larger and thinner the leaflets. Thus, for example,C. latifolia which has the smallest leaflets grows in the driest habitat whereasC. euryphyllidia which grows in the wettest habitat has the largest leaflets in the genus.     

ALLELOPATHIC AND HERBICIDAL EFFECTS OF EXTRACTS FROM TREE OF HEAVEN (AILANTHUS ALTISSIMA)

Mature trees of Ailanthus altissima produce one or more potent inhibitors of seed germination and seedling growth. Inhibitor activity is highest in bark, especially of roots, intermediate in leaflets, and low in wood. Crude extracts of Ailanthus root bark and leaflets corresponding to 34 and 119 mg water extractable material/L, respectively, caused 50% inhibition of cress radicle growth. Ailanthus seeds also contain one or more inhibitors. These are bound within the seed by the pericarp but diffuse into water agar when the pericarp is removed. The inhibitor(s) could readily be extracted from Ailanthus tissues with methanol, but not dichloromethane, indicating polar characteristics. Ailanthus leaflets had highest inhibitory activity during expansion in spring, whereas activity of trunk bark peaked just before emergence of leaves. This pattern suggests transport of allelochemicals from bark into new leaves. A comparison of seven plant species for sensitivity to the inhibitor(s) from Ailanthus root bark showed little selectivity, although velvetleaf was somewhat more resistant. The inhibitor(s) from Ailanthus root bark exhibited strong herbicidal effects when sprayed pre- and postemergence on plants in soil in the greenhouse. Postemergence effects were striking, with nearly complete mortality of all species, except velvetleaf, at even the lowest doses tested. The results suggest the allelochemical(s) from Ailanthus may have potential for development as natural-product herbicides.     

Munronia yinggelingensis sp. nov. (Meliaceae) from Hainan, China

Munronia yinggelingensis R. J. Zhang, Y. S. Ye & F. W. Xing, a new species of Meliaceae from Hainan, China, is described and illustrated. Notes are also presented on the phenology, ecology and conservation status of the new species. The new species was found growing in the valley rain forests of Yinggeling Nature Reserve at altitudes of 600 m a.s.l. in Gaofeng, Baisha County, Hainan Province, China. It is closely related to Munronia delavayi Franch., but differs in its entire or inconspicuously coarsely serrate margins of leaflets, longer inflorescence (8–30  cm), longer calyx lobes (5 mm), shorter coronal tube (1.2–1.5  cm), with white hairs on both sides, shorter coronal lobes (0.6–0.9  cm) and shorter stamen tube (1.8  cm).     

Revision of Leioproctus (Anacolletes) Michener and Description of a New Subgenus Leioproctus (Odontocolletes) (Hymenoptera: Colletidae)

Leioproctus (Anacolletes) is revised to contain only L. (A.) bimaculatus (Smith). A new subgenus, Leioproctus (Odontocolletes) , is erected. Four new species ( Leioproctus (Odontocolletes) asper, L. (O.) cardaleae, L. (O.) erythropyga and L. (O.) xanthozoster) are described and L. callurus (Cockerell), L. nomiaeformis (Cockerell), L. pachyodontus (Cockerell) and L. rudissimus (Cockerell) are transferred.     

Reconstruction of the Leaves of Two New Species of Pseudosmodingium (Anacardiaceae) from Oligocene Strata of Puebla, Mexico

Leaves of two new plants are reconstructed from their isolated leaflets collected from the Oligocene Los Ahuehuetes locality near Tepexi de Rodríguez in Puebla, Mexico. The leaves of Pseudosmodingium mirandae Ramírez-Gardu?o et al. are compound imparipinnate with leaflets of variable morphology. The leaflets of five leaf morphotypes vary from narrow elliptic to lanceolate or lorate; they are symmetrical to slightly asymmetrical, with acute to attenuate apex, acute to cuneate base, and entire to serrate margin. Venation is simple pinnate craspedodromous, with secondary veins slightly curved near their base; secondary veins may dichotomize near the margin to become tertiary veins, and intersecondary veins are small and oblique to the secondary veins. A small number of leaflets assigned to Pseudosmodingium terrazasiae Ramírez-Gardu?o et al. are distinguished from P. mirandae by the leaflet shape, length&rcolon;width ratio, base shape, and apex angle. Morphological comparison of the fossil leaves with leaves of extant species of Anacardiaceae based on numerical analyses indicates a close similarity between P. mirandae and Pseudosmodingium multifolium Rose, while P. terrazasiae is more similar to Pseudosmodingium perniciosum (HBK) Engl. The presence of fossil species with extant relatives that are endemic to Mexico, along with previous reports, indicates that by the Oligocene, some lineages were already in place, although today they form part of the more xeric communities in southern North America.