ISSN:0017-3134    

DOI:10.1080/00173137809428846

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A considerable variation in the size of modernCorylus avellanapollen mounted in silicone oil was noticed. It turned out that a residue of the silicone oil solvent (benzene) prevents shrinkage of the pollen grains, and that size-variations may be due to more or less incomplete evaporation of the solvent. Evaporation at 50[ddot]C is more effective than evaporation at room temperature. Diffusion of solvents from a plastic spatula and from the slide-sealing material may cause a swelling of the pollen. The size of pollen grains compressed by the cover slip may increase slightly due to deformation. Size changes with storage up to 17 years are random, compressed grains do not swell, and the average changes are insignificant. The size ofCoryluspollen from various modern collections is compared.

ISSN:0017-3134    

DOI:10.1080/00173137809428847

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

In single pollen grains, the polar axis should be defined in relation to the actual geometry of the surface of the monads. The ontogenetic definition, referring to the position in the tetrad, is inapplicable in practice, and can lead to confusion.

ISSN:0017-3134    

DOI:10.1080/00173137809428848

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The morphology of the teliospores ofPuccinia smyrniihas been variously described as warted, or reticulate, or a combination of both patterns. Spores were examined by LM and SEM, and shown to be irregularly warted. The sequence of development of the spores was examined by TEM. Four phases of wall differentiation were recognised. The ornamentation results from a differential deposition of secondary wall components, which are concentrated into invaginations of the cytoplasm. The subsequent exsertion of these invaginations, and concomitant disappearance of the primary wall, reveal the irregular warts of the mature spore. This mode of ornament formation is compared with other rust spore forms, and contrasted with that already outlined forPuccinia chaerophylli,a truly reticulatespored Umbelliferous rust. Combined SEM and TEM observations suggest an explanation for the erroneous LM interpretations.

ISSN:0017-3134    

DOI:10.1080/00173137809428849

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The pollen content of the air in Munich was determined during six years (1971 to 1976) using a Burkard spore trap. Samples were taken continuously 24 hours a day from the beginning of February to the end of October. The mean changes of the pollen content in defined volumes of air during the years are summarized in two graphs and 4 tables, showing the most frequently and rarely found pollen types at the sampling site. Pollen of at least 49 taxa were registered. 72% of all pollen could be associated with 5 taxa, namely with grasses, birch, nettle, pine, and elm. A survey of the trees in the neighbourhood of the trap was accomplished to determine the origin of the collected tree pollen.

ISSN:0017-3134    

DOI:10.1080/00173137809428850

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Exposure of a total of more than 5 000 susceptible plants of barley, wheat and oats at Blåvandshuk, the most westerly point of Jutland, Denmark, for periods of several hours when air mass movements from the British Isles across the North Sea occurred, resulted in infections ofErysiphe graminisf.sp.hordei, E. graminisf.sp.tritici, E. graminisf.sp.avenae, Puccinia reconditaf.sp.triticiandP. hordei.Single colony isolates ofErysiphe graminisf.sp.hordeifrom exposures at different sites in 1976 were tested on the barley variety Sultan. The results strongly indicate that the frequency of the gene for virulence on Sultan in the mildew populations in North Jutland is influenced by the high frequency of the same gene for virulence in the mildew populations borne by wind from the British Isles. Zero or low numbers of infections on exposed plants at Blåvandshuk were generally associated with rainy weather at the source area. It is concluded that ideal conditions for both spore release in the British Isles and wind transport across the North Sea occur rather rarely.

ISSN:0017-3134    

DOI:10.1080/00173137809428851

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Analysis of the dinoflagellate generaTenuaandCyclonepheliumindicates that the type species ofTenua, T. hystrix,is assignable toCyclonephelium,and that other species presently placed inTenuashould be reattributed. For their reassignment, the new genusSentusidiniumis proposed and nine species are herein transferred fromTenuatoSentusidinium(two provisionally). Other proposed new combinations includeAptea anaphrissa (ex Doidyx), Cyclonephelium dubium (ex Tenua)andHemicystodinium? taugourdeaui (ex Tenua).A revised diagnosis forCyclonepheliumis presented and the species presently attributed to that genus are listed.

ISSN:0017-3134    

DOI:10.1080/00173137809428852

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A number of palynological terms with their definitions has been circulated among the members of the ICP Working Group on Terminology. As a result, the following terms and definitions are recommended for general use: aperturate, apolar, bilateral, colpate, ectoaperture, endoaperture, heteropolar, inaperturate, isopolar, laesura, -lete, porate, radially symmetric(al). In addition, the following terms were recommended in Paris, 1975: columella, ectexine, endexine, exine, infratectum, intine, layer, nexine, sexine, sole (foot layer), sporoderm, stratum, tectum (complete tectum, partial tectum, absent tectum), wall.

ISSN:0017-3134    

DOI:10.1080/00173137809428853

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue

ISSN:0017-3134    

DOI:10.1080/00173137809428845

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor