1. |
Cytochemical and infrastructural aspects of pollen and tapetum ontogeny insilene dioica(caryophyllaceae) |
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Grana,
Volume 20,
Issue 2,
1981,
Page 65-80
Jean-Claude Audran,
Mekinto Batcho,
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摘要:
Cytochemical modifications and ultrastructural transformations of pollen and tapetum were studied inSilene dioica(L.) Clairv. Meiosis leads to the formation of simultaneously septated tetrads. Ectexine is elaborated under the callose wall within a polysaccharic, fibrillar primexine. Endexine is formed after dissolution of the callose wall. During the vacuolization and enlargement of the microspores the structure and the chemical composition of the exine are modified. The tapetum is of the secretory type. Its cell walls are destroyed as soon as the tetrad stage is completed. Orbicules of large size and irregular shape are formed in the periplasmic spaces. Tapetal cells are modified, liberating a quantity of tryphine in the anther loculus.
ISSN:0017-3134
DOI:10.1080/00173138109427649
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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2. |
Etude ontogénique de la pollinie deCalotropis procera(Asclepiadaceae) |
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Grana,
Volume 20,
Issue 2,
1981,
Page 81-99
Iléontine dan Dicko-Zafimahova,
Jean-Claude Audran,
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摘要:
L'étude ontogénique de la pollinie deCalotropis proceraa permis de définir deux phases distinctes dans la formation de l'exine. Dans un premier temps, la sporopollénine se matérialise sous la forme de granules qui vont constituer la partie externe de l'exine (exine 1): les granules les plus superficiels fusionnent en un épais tectum continu autour de la pollinie, tandis que les granules sous-jacents restent séparés et forment la strate infratectale grenue. Dans un deuxième temps, la sporopollénine se dépose sur des systèmes lamellaires, formant ainsi la partie profonde feuilletée de l'exine (exine 2). Les différents composants de cette exine paraissent issus de l'activité des cellules microsporales.
ISSN:0017-3134
DOI:10.1080/00173138109427650
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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3. |
Key for northwest european rosaceae pollen |
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Grana,
Volume 20,
Issue 2,
1981,
Page 101-118
Frøydis Eide,
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摘要:
All main types of pollen grains in Rosaceae seem to be variations of the same theme: a tricolporate pollen, with or without operculum. In most cases the exine sculpture is the best feature for classification; and combined with other characteristics, it is possible to separate some species earlier considered undistinguishable.
ISSN:0017-3134
DOI:10.1080/00173138109427651
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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4. |
Études palynologiques sur les sédiments préquaternaires de l'Egypte. Néogène I |
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Grana,
Volume 20,
Issue 2,
1981,
Page 119-130
Miklós Kedves,
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摘要:
Cette étude est la première d'une série concernant les associations sporo-polliniques préquaternaires de l'Egypte. Dans cet article les spores, les pollens des Gymnospermes et les Bréviaxes des Angiospermes sont présentés. Dix espèces de forme nouvelle sont décrites. Vue la composition des sporomorphes présentés, les formes monoporées et périporées sont riches en espèces. L'interprétation détaillée prendra place dans la deuxième partie, après la fin de la partie taxonomique des couches Néogènes du Wadi el Fharigh et du Wadi el Natrun.
ISSN:0017-3134
DOI:10.1080/00173138109427652
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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5. |
An evaluation of the microscopical counting methods of the tape in hirst-burkard pollen and spore trap |
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Grana,
Volume 20,
Issue 2,
1981,
Page 131-141
Markku Käpylä,
Antti Penttinen,
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摘要:
Three different sampling units in current use and different sampling strategies were tested. Randomly placed microscope fields are good in estimating the daily mean concentration, but very big sample size is needed. Traverses across the slide in systematic order are best to estimate the shortterm concentrations and diurnal variation. A formula for the estimation of the error in one transverse traverse is given. Twelve transverse traverses in systematic order is also enough to estimate the daily mean concentration. One or two traverses along the length of the slide give often unreliable estimates because of the irregularities in the transverse variation of the particle concentrations on the slide. For the same reason it is not safe to choose an “effectively collecting area”. Instead the whole width of the tape should be studied.
ISSN:0017-3134
DOI:10.1080/00173138109427653
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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6. |
A note on viscin threads |
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Grana,
Volume 20,
Issue 2,
1981,
Page 143-143
Knut Faegri,
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ISSN:0017-3134
DOI:10.1080/00173138109427654
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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7. |
Editorial board page for “Grana”, Volume 20, Number 2 |
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Grana,
Volume 20,
Issue 2,
1981,
Page -
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PDF (68KB)
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摘要:
This is a scanned image of the original Editorial Board page(s) for this issue
ISSN:0017-3134
DOI:10.1080/00173138109427648
出版商:Taylor & Francis Group
年代:1981
数据来源: Taylor
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