Results 181 to 190 of about 24,573 (227)

Pollen wall stratification and pollination

Plant Systematics and Evolution, 2000
Qualities of the stratified pollen walls were evaluated for their possible role in pollination (pollination modes, and pollen tube formation). The importance of studying pollen grains in their respective natural state is noted. Examples of pollen morphological features specific to pollination vectors are rare and difficult to demonstrate. However, some
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Uncommon pollen walls: reasons and consequences).

Verhandlungen der Zoologisch-Botanischen Gesellschaft in Osterreich, 2011
The mature pollen wall of gymnosperms and angiosperms consists in principle of two fundamentally different layers, the complex, thick sporopolleninous exine and the homogeneous, thin, single-layered pectocellulosic intine. In angiosperms, the typical exine is usually formed by a tectum, columellae, a foot layer, and an endexine.
Pacini, Ettore, Hesse, Michael
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FINE STRUCTURE OF PARKINSONIA ACULEATA POLLEN. I. THE POLLEN WALL

American Journal of Botany, 1961
Larson, Donald A., and C. Willard Lewis, Jr. (U. Texas, Austin.) Fine structure of Parkinsonia aculeata pollen. I. The pollen wall. Amer. Jour. Bot. 48(10): 934–943. Illus. 1961.—Fresh pollen samples and chemically fossilized pollen samples were fixed in either potassium permanganate or osmium tetroxide and some sectioned material was poststained in an
Donald A. Larson, C. Willard Lewis
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Effects of 60Co-irradiation and superfine grinding wall disruption pretreatment on phenolic compounds in pine (Pinus yunnanensis) pollen and its antioxidant and α-glucosidase-inhibiting activities.

Food Chemistry, 2020
Effects of 60Co-irradiation and superfine grinding wall disruption on the phenolic, antioxidant activity, and α-glucosidase-inhibiting potential of pine pollen were investigated.
Yong Cheng, Wei Quan, Tao Qu, Yujie He, Zhaojun Wang, Maomao Zeng, Fang Qin, Jie Chen, Zhiyong He   +8 more
semanticscholar   +1 more source

Breaking strengths of pollen grain walls

Plant Systematics and Evolution, 1992
50% breaking point pressures of pollen grain walls of eleven species were determined. The breaking point pressures of most pollen grain walls are equivalent to those reported in the literature for other types of living cell walls such as bacterial spore coats, algal cell walls, mold sporophyte cells, and dicot suspension culture cells.
M. R. Bolick, S. Vogel
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Effect of ultrasonic and ball-milling treatment on cell wall, nutrients, and antioxidant capacity of rose (Rosa rugosa) bee pollen, and identification of bioactive components.

The Journal of the Science of Food and Agriculture, 2019
BACKGROUND Bee pollen has been regarded as a complete nutritional human dietary supplement but its nutrient absorption and biological effects may be restricted by the complex pollen wall. The aim of this study was to explore the effects of ultrasonic and
Yang Yang, Jiu‐liang Zhang, Qing Zhou, Lin Wang, Wei Huang, Rui-dan Wang   +5 more
semanticscholar   +1 more source

Pollen wall proteins: Pollen-Stigma interactions in ragweed and Cosmos (compositae)

Journal of Cell Science, 1973
ABSTRACT The release of wall-held materials from the pollen of ragweed (Ambrosia tenuifolia) and Cosmos bipimuxtus on to the stigma surface has been followed. When fresh stigmas were viewed by scanning electron microscopy, a fluid material was observed coating pollen grains, pollen tubes and adjacent stigmatic papillae.
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Pollen Wall Development of Austrobaileya maculata

Botanical Gazette, 1984
Pollen wall development of Austrobaileya maculata was investigated from the initiation of pollen mother cells to anthesis. Pollen wall development can be divided into three phases: premeiotic, tetrad, and free spore. The ektexine develops within the tetrad phase and follows the pattern for other tectate-columellate angiosperm pollen thus far ...
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Cold stress affects cell wall deposition and growth pattern in tobacco pollen tubes.

Plant Science, 2019
Cold is an abiotic stress seriously threatening crop productivity by decreasing biomass production. The pollen tube is a target of cold stress, but also a useful model to address questions on cell wall biosynthesis.
L. Parrotta, C. Faleri, G. Guerriero, G. Cai   +3 more
semanticscholar   +1 more source

Analysis of AGP contribution to the dynamic assembly and mechanical properties of cell wall during pollen tube growth.

Plant Science, 2019
Arabinogalactan proteins as cell wall structural proteins are involved in fundamental processes during plant development and growth. The aim of this study was to evaluate AGP function in the distribution of pectin, cellulose and callose along Fragaria x ...
Agata Leszczuk, A. Kozioł, E. Szczuka, A. Zdunek   +3 more
semanticscholar   +1 more source