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1

Ecological adaptation of the seed microsculptures of Saussurea from different altitudes (Qinghai-Tibet Plateau)

100%
Li Z., Du G.
Polish Journal of Ecology
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2015
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tom 63
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nr 4
The aim of this study was to explore ecological adaptation of seed microsculptures of Saussurea from different altitudes. Scanning electron microscopy was used to observe the cypselae surface of 10 taxa of Saussurea collected from the eastern edge of Qinghai-Tibet plateau, China. The results indicated that the microsculptures had clear and consistent variations in some samples collected from high (4200 m a.s.l.) and low-altitude sites (2200 m a.s.l.). The thickness of stripes and distance between stripes are increasing while sulcus depth is increasing from a low to a high altitude (P < 0.01). The seed-coat surface was becoming rougher from low to high altitude. The surviving rate of seeds was lower at high altitude than that at low altitude in all the species. The surviving rate of the seeds collected from the high altitudes was higher than that of the seeds collected from low altitudes when sown at the same altitude. All the results suggested that there is selection pressure of the altitude on the development of the microsculpture patterns, which increases absorbed sunlight, the residence time of soil water and nutrition. The changes can make the seeds survive better at extreme environments (cold and dry). The cypselae microsculpture patterns should be used as potential adaptation biomarkers for the species of Saussurea from low- to high-altitude.
2
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Ecological adaptations of the floral structures of Galanthus nivalis L.

84%
Weryszko-Chmielewska E., Chwil M.
Acta Agrobotanica
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2010
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tom 63
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nr 2
The structure of the flowers of Galanthus nivalis shows adaptations to early spring flowering conditions as well as adaptations to entomogamy. The tepals produce colour marks and odorous substances. The aim of the present study was to determine the micromorphology and anatomy of tepals, in particular in the regions comprising colour marks which, in accordance with the literature data, emit essential oils. Examination was performed using light, fluorescence, and scanning electron microscopy. Large protrusions, corresponding to the location of the green stripes, were found to occur on the adaxial surface of the inner tepals. The epidermal cells in this part of the tepals produce a cuticle with characteristic ornamentation as well as numerous stomata with well-developed outer cuticular ledges. The wide opening of many stomata is evidence of high activity in this area. The fluorescence microscopy images confirm the high activity of the epidermis (scent emission), on both sides of the tepals, as well as of the chloroplast- containing mesophyll. In the abaxial epidermis, there were observed different-sized papillae that also participated in essential oil secretion. The polarization of the epidermal cell protoplasts, large cell nuclei, and the presence of large vacuoles with heterogeneous contents in the peripheral part of the cells correspond to the structural features of the tissues emitting odorous compounds in flowers – osmophores. In freshly opened flowers, the mesophyll of the central part of the perianth segments was composed of several cell layers, whereas in older flowers large air ducts formed, which are adaptations to environmental thermal conditions.
3

Ecological adaptation strategies in alien species: effects of salinity, temperature and photoperiod on Spartina alterniflora Loisel. seed germination

84%
Yuan Z., Shi F.
Polish Journal of Ecology
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2009
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tom 57
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nr 4
677-683
Spartina alterniflora (smooth cordgrass), a perennial grass native to the coastal marshes of eastern America, is widely distributed in northern China since 1979 of its introduction. In the tidal marshlands of north China, S. alterniflora has displaced native species and is presently dominant member of the community owing to its opportunistic characteristics. In this study we investigated S. alterniflora seed germination responses to different temperatures, between 5–25ºC in one thermoperiod (16/26ºC) and in two light treatments – 10/14h (night/day) photoperiod and dark conditions. Variations of seed germination at different storage temperatures and storage duration were also examined. In addition, the effect of different salt concentrations on seed germination was evaluated. The optimal temperature for germination was 25ºC and 16/26ºC (night/day) thermo-period – germination percentage was greater than 90%. Light intensity had no influence on the percent of seed germination and germination indices when seeds were exposed to identical temperatures. At 120 d of storage and -5, 0, and 5ºC temperatures, germination percentage exceeded 75%. The optimal salinity level for seed germination was 150 mM NaCl. Germination percentages were highest (> 90%) when salinity did not exceed 450 mM NaCl. The ability of S. alterniflora seeds to germinate under a wide range of temperature and light conditions resulted in continued seedling development under high salinity.
4
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Adaptation of existing livestock buildings to ecological requirements of selected organic farms in the Lublin Voivodeship

67%
Dabkowski N., Redzik K.
Acta Scientiarum Polonorum. Architectura
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2021
|
tom 20
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nr 4
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