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1522. C3 and C4 photosynthetic pathways and life form types for native species from agro-forestry region, Northeastern China

Creator:
Wang, R. Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
agro-forestry region, C3 and C4 species, CAM plants, and Tumen Mountains
Language:
Multiple languages
Description:
Of the total 570 species, 194 species in 116 genera and 52 families were found with C3 photosynthesis, 24 species in 17 genera and 6 families with C4 photosynthesis, and 2 species in 1 genera and 1 family with CAM photosynthesis. 90 % of the total species can be found in Changbai Mountain flora, more a half (69 %) in North China flora, and about 1/3 in Mongolian flora and Xinan flora, respectively. The occurrence of C4 species was not as common as that in adjacent grasslands and deserts, but relatively more than in the adjacent forests. Of the total 24 C4 species, 63 % C4 species (15 of 24) was found in Gramineae. Nine life form types can be found, reflecting the moist climate in the region, especially the occurrence of epiphyte and liana forms. Relatively more geophyte life form plants suggested the winter in the region was much colder than in grasslands. These indicated that both ecological studies and land management decisions must take into account plant photosynthetic pathway and life form patterns, for both of them are closely related to climatic changes and land use.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1523. C4 plants in the deserts of China: occurrence of C4 photosynthesis and its morphological functional types

Creator:
Wang, R. Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
annual plants, Chenopodiaceae, forbs, grasses, and shrubs
Language:
Multiple languages
Description:
C4 photosynthetic pathway and morphological functional types were determined for 104 species in 45 genera and 10 families from the deserts of China. 67 C4 species (64.4 %) were found in Dicotyledoneae (e.g. Chenopodiaceae, Polygonaceae, and Amaranthaceae), the other 37 species were in Monocotyledoneae (e.g. Gramineae, Cyperaceae, and Commelinaceae). 36.5 % of the Chenopodiaceae species (predominantly members of the genera Anabasis, Atriplex, Kochia, Salsola, and Suaeda) identified in the desert regions were found with C4 photosynthesis, which was about 48 % of the total C4 species. Many C4 species (58.7 %) were annuals (e.g. Amaranthus, Atriplex, Digitaria, Eragrostis, Kochia, and Salsola) and experienced long-term droughts, high temperature, and high irradiance. Relatively more shrub C4 species (28 species of 104) were found in Chenopodiaceae (e.g. Anabasis, Camphorosma, Haloxylon, and Salsola) and Polygonaceae (e.g. Calligonum) in the desert regions. Most of shrub C4 species with small leaf area were no more than 1 m in height and distributed in sandy soils. Composition of relatively more annual species, shrubs, and Chenopodiaceae C4 species was the primary characteristic for the C4 species occurrence in deserts, and this was remarkably related with the arid environmental conditions.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1524. C4 plants in the vegetation of Tibet, China: Their natural occurrence and altitude distribution pattern

Creator:
Wang, R. Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
altitude distribution, geophytes, habitat types, hemicryptophytes, plant life form, precipitation, therophytes, and Tibet Plateau
Language:
Multiple languages
Description:
Floristic composition, life forms for C4 species, and the pattern of altitude distribution were studied on Tibetan Plateau. 79 species, in 7 families and 46 genera, were identified with C4 photosynthesis. 95 % of these C4 species belong to Gramineae (51 species), Cyperaceae (14 species), and Chenopodiaceae (10 species), indicating that C4 plants mainly occur in very few families (7 of 204) on the Tibetan Plateau. High altitude distribution for all the Chenopodiaceae C4 species (> 3 000 m above sea level) suggests that plants of this kind have large tolerance to cold, dryness, and strong ultraviolet radiation. Most Gramineae and Cyperaceae C4 species occurrences are consistent with extensive distribution of steppes and meadows in the vast flat of the central Plateau (1 000-3 000 m a.s.l.). Relatively high amount of hemicryptophyte form plants (44 %) in the region indicates that the vegetation, especially grassland, meadows, and steppe, are in good condition. There is a strong relationship between numbers of C4 species and altitude in the Tibetan Plateau. Occurrence of C4 species is significantly less in both high and low altitude plateaux in Tibet. Altitude distribution pattern for C4 species in the region is not only consistent with the altitude and climate, but also with the vegetation types in altitude gradient.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1525. C4 species and their response to large-scale longitudinal climate variables along the Northeast China Transect (NECT)

Creator:
Wang, R. Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
C4 plants, climatic pattern, large-scale longitudinal gradient, and life form
Language:
Multiple languages
Description:
Natural occurrence of C4 species, life forms, and their longitudinal distribution patterns along the Northeast China Transect (NECT) were studied. Six vegetation regions experiencing similar irradiation regimes, but differing in longitude, precipitation, and altitude were selected along the NECT from 108 to 131 °E, around altitude of 43.5 °N. Seventy C4 species were identified in 41 genera and 13 families. 84 % of the total C4 species were found in four families: Gramineae (38 species), Chenopodiaceae (11 species), Cyperaceae (5 species), and Amaranthaceae (5 species). C4 grasses make up 54 % of the total identified C4 species along the NECT and form the leading C4 family in meadow, steppe, and desert along the NECT. C4Chenopodiaceae species make up about 16 % of the C4 species and become less important, particularly in the meadow and the eastern end of the NECT. 57 % of the total C4 species are therophytes and 37 % are hemicryptophytes, which is consistent with floristic composition and land utilization. In general, the number of C4 species decreased significantly from the west to the east or from dry to moist areas along the NECT, and was remarkably correlated with annual precipitation (r2= 0.677) and aridity (r2= 0.912), except for salinized meadow region. The proportion of C4 species from all the six vegetation regions was considerably correlated with these two climatic parameters (r2= 0.626 or 0.706, respectively). These findings suggest that the natural occurrence of C4 species varies significantly along the large-scale longitudinal gradient of the NECT. The notable relationship of C4 species number and proportion in the flora with variations in annual precipitation and aridity suggest that these two climatic parameters are the main factors controlling the longitudinal distribution patterns of C4 species along the NECT.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1526. Ca-ATPase of human myometrium plasma membranes

Creator:
Carrera, F., Proverbio, T., Marín, R., and Proverbio, F.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, hladké svaly, smooth muscles, calcium adenosine triphosphatase, human myometrium, 14, and 612
Language:
English
Description:
We determined and characterized the Mg2+-dependent, Ca2+-stimulated ATPase (Ca-ATPase) activity in cell plasma membranes from the myometrium of pregnant women, and compared these characteristics to those of the active Ca2+-transport already demonstrated in this tissue. Similarly to the Ca2+-transport system, the Ca2+-ATPase is Mg2+-dependent, stimulated by calmodulin, and inhibited by vanadate. The Km for Ca2+ activation is 0.40 m M, very similar to that found for active calcium transport, i.e. 0.25 m M. Consequently, this Ca2+-ATPase can be responsible for the active calcium transport across the plasma membranes of smooth muscle cells., F. Carrera, T. Proverbio, R. Marín, F. Proverbio., and Obsahuje bibliografii
Rights:
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1529. Cadmium and zinc induced chlorosis in Indian mustard [Brassica juncea (L.) Czern] involves preferential loss of chlorophyll b

Creator:
Ebbs, S. and Uchil, S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heavy metals
Language:
Multiple languages
Description:
Plants of Indian mustard (Brassica juncea) were treated with either 50 µM Cd, 250 µM Zn, or 25 µM Cd+125 µM Zn and the progression of chlorosis in the mature leaves monitored. As relative chlorophyll (Chl) contents in the mature leaves decreased to 75, 50, and 25 % relative to controls, both mature and young leaves were harvested and the Chl pools extracted. The metal treatments caused a greater loss of Chl b than Chl a. As mature leaves underwent progressive chlorosis, the young leaves displayed a characteristic over-greening, due largely to increased content of Chl b. However, as the young leaves began to experience chlorosis, a greater loss of Chl b was also observed. Thus during metal induced chlorosis, there is a preferential turnover of the Chl b pool in mature and young leaves. and S. Ebbs, S. Uchil.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1530. Cadmium chloride toxicity revisited: effect on certain andrological, endocrinological and biochemical parameters of adult male rabbits

Creator:
Sajjad, S., Malik, H., Farooq, U., Rashid, F., Nasim, H., Tariq, S., and Rehman, S.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, kadmium, kortizol, cadmium, cortisol, endocrine disruptors, prolactin, 14, and 612
Language:
English
Description:
The present study was devised to assess the effects of cadmium chloride (CdCl2) administration on certain andrological, endocrinological and biochemical alterations in adult male rabbits (n=24). The animals were assigned to control (n=8) and experimental (n=16) group. Experimental group was orally administered with 1.5 mg/kg body weight of CdCl2. The trials were carried out for a total of 5 weeks and blood sampling was carried out on weekly basis. A gradual decrease was noticed for body weight in the experimental group from week 1 to 5, being significantly lower in week 4 and 5 (P<0.05). A similar decremented trend was noticed for serum testosterone level being significantly lower in experimental group in week 4 and 5 (P<0.001). Significantly lower values were noticed for prolactin in experimental group in week 4 and 5 (P<0.05), than in the control. On the contrary, serum cortisol level showed a gradual increase in experimental group, from week 1 to 5, being significantly higher in week 4 and 5 (P<0.05). Regarding the biochemical attributes, all the parameters under study revealed a gradually ascending trend. Statistical significance was, however, achieved in varying weeks and at varying levels. The total protein and albumin were significantly higher in week 4 and 5 (P<0.01); alanine aminotransferase in week 2 (P<0.01), 3 (P<0.001), 4 (P<0.01) and 5 (P<0.001); aspartate aminotransferase in week 1, 2, 3, 4 and 5 (P<0.01); and alkaline phosphatase in week 1, 2 (P<0.01), 3, 4 and 5 (P<0.0001), respectively. Overall mortality rate in experimental group was 68.75 (11/16). In a nutshell, Cd exposure results in adverse effects on all physiological parameters of body and may lead to lethal consequences., S. Sajjad, H. Malik, U. Farooq, F. Rashid, H. Nasim, S. Tariq, S. Rehman., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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