摘要:

The occurrence ofLeymus arenariusas a constituent of the Greenlandic flora is confirmed. The different patterns of hairiness of the rachis segments characteristic ofL. mollisandL. arenarius, respectively, were found to correlate with endospermal protein patterns fractionated with SDS‐PAGE (sodium dodecylsulphate, polyacrylamide gel electrophoresis). The characteristics of its protein patterns were substantiated by a transect study ofL. arenariusthrough Fennoscandia. The northern populations ofL. mollisandL. arenariusdisplayed no or relatively little variation in endospermal protein patterns within plants or sites. This may reflect a prevailing self‐pollination, founder effect, clonal spreading of stands and selection or any combination thereof. The key proteins of 120 to 140 kg mole‐1demarcatingL. mollisandL. arenariuswere shown to be soluble in 50% isopropanol at pH 8.0, and hence to be prolamins, which were also found to carry glycosylation. The spontaneous, sterile hybrids of these species in Greenland have an intermediary morphology. A hybrid clone may form relatively wide stands in South and Southwest Gree

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01235.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

After its arrival in E Greenland c. 8000 C‐14 years B.P.Betula nanaspread rapidly to become a dominant plant. A climatic change c. 5000 B.P. almost exterminated it at more oceanic sites, whereas inland it only lost little ground. Today it is common inland in many kinds of heath and other vegetation types. When it spread to Middle W Greenland around 6500 B.P. it only took two to three centuries to become dominating in the continental inland whereas the spreading to the coastal areas began later and was more gradual. After the Holocene climatic optimum it decreased here but kept its dominating position inland, where today it is a main plant in mossy heaths on N slopes and dry, grassy communities on S slopes.Betula glandulosaarrived in SW Greenland c. 5 700 B.P., later on in S Greenland. It is a lowarctic, oceanic plant, missing only on the outer skerries, but being common in mossy heaths all through the fjords, where it also occurs in grassland vegetation types and, at the head of the fjords, as undergrowth in the subarctic, usually 4–5 m high birch woodlands formed byB. pubescens, which did not arrive until c. 3500 B.P. The most common plant communities, in which the threeBetulaspecies occur in different parts of Greenland are summarized, partly by referring to other publications, partly by presenting six new tables of vegetation analyses, stored in the Botanical Museum or published in “grey literature”. Where the species meet, hybridizing and introgression take place. Distribution maps of the three species and two hybrids are presented, and the taxonomy sum

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01236.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The circumscription ofJatrophasect.Robecchianais widened to include also the members of/, sect.Spinosasubsect.Parvifoliae.Seven species are recognized in the group that is confined to arid regions of NE and E tropical Africa. New taxa areJ. rivaessp.quercifolia, J. horizontalis, J. tenuicaulis, andJ. euarguta.A new combination isJ. rivaessp.parvifolia.Two lectotypes are selected.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01237.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01238.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Croton crispatus, sp. nov., fromAcacia‐Commiphorabushland on sand in central Somalia, is described and illustrate

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01239.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01240.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Momordica littorea, sp. nov., a dioecious climber with succulent 3‐foliolate leaves and conspicuously bracteate flowers from coastal regions of southern Somalia and Kenya, is described and illustrate

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01241.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01242.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The Amazon palm genusLeopoldiniaexemplifies the transition from a terrestrial to an amphibious life‐style, accompanied by a switch from synzoochorous dispersal to hydrochory.Leopoldinia piassabaproduces heavy fruits with a fleshy, sweet mesocarp and is presumed to be dispersed by terrestrial animals. This species enters aquatic habitats only so far as these are submersed for a short while. The other two species,L. majorandL. pulchra, resist long‐lasting submersion and have much smaller, buoyant fruits, which are dispersed by water and are produced in proportionately larger guantities. They are eaten and mostly destroyed, but occasionally probably also dispersed by fish.L. pulchra, the species with the smallest fruits, has acquired the widest geographical distribut

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01243.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The neotropical generaBrowneaandBrowneopsisare understorey trees and shrubs of lowland rain forest comprising twelve and six species, respectively. Four species ofBrowneaand three ofBrowneopsisoccur in Ecuador. Keys to the genera and species in Ecuador are provided, andBrownea coccinea, B. grandiceps, B. macrophylla, B. multijuga, Browneopsis disepala, B. ucayalina, andB. macrofoliolataare described, the last‐named as a new species. Additionally, the intergeneric relationships, and the morphological and the palynological variation in the genera are surveye

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1991.tb01244.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY