ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00674.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYThe root patterns ofRumex palustris(Sm.),Rumex acetosa(L.) andPlantago major(L.) ssp.major, three species occurring in the river forelands, were studied in experimentally waterlogged or drained compacted soils and compared with specimens growing in drained loosely packed‐soils as a control. A modified method for endoscopy in root boxes was developed. The species studied showed different patterns of root development as a result of soil waterlogging or compaction.R. palustriswas the least sensitive to waterlogged soils, as shown by the formation of new, morphologically distinctive roots;R. acetosawas the most sensitive andP. majorhad an intermediate response. With respect to soil compactionP. majorwas the least affected species, followed byR. acetosaandR. palustris, respectively. The fractional root porosity of these species was studied by using a flow‐through system to create hypoxia, a small soil‐pore diameter or a combination of both. Hypoxia resulted in a higher root porosity. In bothRumexspecies small soil‐pores inhibited this increase. Contrasting results were found for the porosity ofPlantagoroots. Results are discussed in relation to the distribution of these species in th

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00675.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYThe morphology of light sprouts produced by tubers of the wild relatives of the cultivated potato was studied in order to determine its usefulness for the classification of wild tuberiferousSolanumspecies. Light sprout morphology is routinely used in tests to distinguish potato cultivars but it has not yet been applied to wild species. An advantage of this method is that the influence of environmental factors on the morphological characters of these phenotypically plastic plants is avoided. The results indicate that light sprout morphology can be used to characterize species and species groups. The implications for the current taxonomic system of the wild tuberiferousSolanumspecies are discussed.

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00676.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYEpidermal morphology of adaxial and abaxial leaf surfaces of five genera of the family Rhizophoraceae in Nigeria were studied by light microscopy. The epidermises are composed of variously shaped cells which, in surface view, range in outline from triangular, rectangular to more commonly hexagonal, polygonal and irregular. Cuticular striations are absent except inPoga oleosain which conspicuous striae encircle the guard cells and run parallel to the axis of non‐specialized epidermal cells. Anticlinal walls are either straight, curved or undulate. Leaves of all genera are hypostomatic. Paracytic stromata occur inCassipoureaandAnisophylleawhile all species ofRhizophorapossess cyclocytic stomata. The stomata ofAnopyxisare of the anisocytic type and thoseof Pogaanomocytic. The morphology of the guard cells and stomatal ledges varies significantly within the family. Evidence is produced to support the suspected hybrid natureof Rhizophora harrisonii. Other features of the epidermis that show variation include stomatal size, shape and density, size and density of epidermal cells, and cell wall thickness. Epidermal characters are of some utility in elucidating relationships and identifying some taxa within the famil

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00677.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYThree salt‐tolerant (ILL 6451, ILL 6788, ILL 6793) and two salt‐sensitive (ILL 6439 and ILL 6778) accessions of lentil(Lens culinarisMedic.) were grown for 42 days in sand culture salinized with 0 or 30 mol m−3NaCl in full strength Rorison nutrient solution in order to determine the physiological/biochemical mechanisms responsible for their salt tolerance. All three salt‐tolerant accessions produced significantly greater shoot and root biomass than the two salt‐sensitive accessions after the salt treatment. Of the salt‐tolerant accessions, ILL 6451 and ILL 6788 had significantly higher leaf water potentials but lower osmotic potentials than the other accessions under saline conditions. Leaf diffusive resistance and epicuticular wax content were significantly higher in the two sensitive accessions compared with the tolerant accessions after the salt treatment. Leaf soluble proteins decreased due to NaCl treatment but to the same extent in both tolerant and sensitive accessions. Total free amino acids and non‐reducing sugars were relatively low in the two salt‐sensitive accessions after the salt treatment. Reducing sugars of the tolerant accessions remained unaffected due to NaCl, whereas those of ILL 6439 increased and of ILL 6778 decreased. Leaf free amino acids and non‐reducing sugars appeared to have contributed, to some extent, to the salt tolerance of to

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00678.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYAgrostis stoloniferais a polyploid complex in which clonal propagation is predominant. Polyploidization often results in the induction of chromosomal aberrations at the mitotic and/or meiotic level. We observed that variation in ploidy level was present inAgrostis stolonifera, and that variation in chromosome number within genotypes also occurred. Populations differed in the degree of variation observed. Analysis of the frequency distribution of chromosome numbers per cell among different populations showed a wide range of variation in the inland meadow population, an intermediate level in the polder and salt marsh populations, and a very low level in the sand dune population. The results are discussed in the context of the origin of somatic chromosome number variation.

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00679.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

SUMMARYWe investigated variation in two traits that determine generation time, cold‐ and size‐requirement for flowering, within and among European populations for the monocarpic perennialCynoglossum officinale. When grown in an experimental garden in Leiden, no annual individuals were found among plants originating from 22 locations; all plants were biennial under nutrient‐rich growing conditions. In a controlled‐environment experiment, in which plants received an artificial cold treatment, flowering probability increased gradually with plant size for plants from two natural populations, signifying a large within‐population variation in threshold size for flowering. The relationships between plant size and flowering of these two groups were significantly different: plants from Holkham (England) had much higher threshold sizes than plants from Meijendel (The Netherlands). Three plant groups originating from botanic gardens showed a sharp increase in flowering probability with size, indicating less variation in threshold size. Significant differences existed among all five groups. Results indicate the possibility that natural selection acts upon threshold size for flowering inCynoglossum o

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00680.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00681.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Book reviewed in this article:Plant Root Growth: An Ecological PerspectiveD. Atkinson (ed.).Botanisch Basisregister. [Botanical Basic Register]*Uitgebreide versie [Complete edition] CBS‐103D/1991‐2, Dfl. 120.00. MS‐DOS [only], ASCII format, 1–3 Megabyte (2 diskettes of 3 1/2 inch).*Beknopte versie [Abridged edition] CBS‐103D/1991‐1, Dfl 60.00. MS‐DOS [only], ASCII format, 0.5 Megabyte (3 diskettes of 5 1/4 inchor 1 of 3 1/2 inch).*Beknopte versie [Abridged edition] CBS‐103/1991, Dfl 25.00, ISBN 906786 413 7 Printed edition. Netherlands Central Bureau of Statistics, Voorburg/Heerlen.The Genus Dombeya (Sterculiaceae) in Continental AfricaJ.H. Seyani.Microclimate, Vegetation and FaunaF. Stoutjesdijk and J.J. BarkmanZeigerwerte von Pflanzen in MitteleuropaH. Ellenberg, H.E. Weber, R. Düll, V. Wirth, W. Werner and D. Paulißen.Feuchtwälder im Nordwestdeutschen Tiefland; Gliederung‐Ökologie‐SchutzU. Döring‐Mederake. Verlag Erich Götze, Göttingen.Geschichte der Botanik. Leben und Leistung großer ForscherK. Mägdefrau. Gustav Fischer VerlagMorphology of Flowers

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00682.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0044-5983    

DOI:10.1111/j.1438-8677.1993.tb00683.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY