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111.
Věra Sosnová 《Biologia Plantarum》1965,7(6):472-473
P?i studiu klí?ních rostlin raj?at pěstovaných ve vodních kulturách bylo zji?těmo, ?e ko?eny rostlin infikovaných TMV vylu?ují do kultia?ního média látky, které p?sobí toxicky na neinfikované rostliny rostoucí spole?ně v tém?e médiu. 相似文献
112.
Calamagrostis villosa stands occurring in areas deforested by air-pollution impact in the Moravian-Silesian Beskydy Mountains were characterized by a high dry mass of total underground biomass (3 300 g. m?2—the slope site, 2 850 g. m?2—the flat site). The percentage of living roots and rhizomes in total underground biomass was very high (about 70%). The total aboveground biomass was respectively, 321 g.m?2 (the slope site) and 726 g. m?2 (the flat site). In unstabilized habitats on steep slope, the higher plant biomass produced was allocated to a more developed root system. 相似文献
113.
114.
Further characterization of four lipocortins from human peripheral blood mononuclear cells 总被引:1,自引:0,他引:1
C Coméra B Rothhut J C Cavadore I Vilgrain C Cochet E Chambaz F Russo-Marie 《Journal of cellular biochemistry》1989,40(3):361-370
Four calcium and phospholipid binding proteins purified from mononuclear cells were characterized for PKC and EGF phosphorylation, actin binding capacity, and partial tissue distribution. Those named 35K, 32K, and 73K are equivalent, respectively, to lipocortin III, endonexin II and the 67 kDa calelectrin; 36K is a fragment of 73K. After purification, 35K and 73K were phosphorylated by protein kinase C in vitro but 36K nor 32K were not. None were phosphorylated by the epidermal growth factor receptor kinase in vitro; 73K bound F-actin in a calcium-dependent manner, whereas 35K, 36K, and 32K did not. Using Western blotting analysis, 32K and 73K were detected in high amounts in human lymphocytes, monocytes, liver, and placenta and in rat adrenal medulla; but 32K was not detected in polymorphonuclear cells, and 36K and 35K were detected in high amounts only, respectively, in human blood lymphocytes and polymorphonuclear cells. Thus, 32K and 73K appear to have a wide tissue distribution, whereas 35K has a much more restricted distribution. 相似文献
115.
Stand microclimate and physiological activity of tree leaves in an oak-hornbeam forest 总被引:1,自引:0,他引:1
Michal Marek Elena Masarovičovà Irena Kratochvílová P. Eliáš D. Janouš 《Trees - Structure and Function》1989,3(4):234-240
Summary In an uneven-aged, multi-species oak-hornbeam forest at Báb, SW Slovakia (former IBP Forest Research Site), a series of micrometeorological and ecophysiological measurements started in 1985. The aims of the work are to improve understanding of physiological processes (photosynthesis, respiration, and transpiration) of adult trees and stand microclimate, to collect data for simulation of the canopy (stand) photosynthesis and for ecological synthesis of the functioning of the forest ecosystem. In this paper, photosynthetically active radiation (PAR), air temperature (AT) and relative humidity (RH), wind speed (WS), and CO2 concentration ([CO2]) in and above the forest are characterized for the fully leaved season, using diurnal courses, vertical profiles and isodiagrams (isopleths). Approximately 50% of incident PAR was absorbed by the upper 4–5 m layer of leaves and only approximately 5% or less penetrated to the forest floor. Vertical gradients of AT and RH were generally low, but large differences in diurnal ranges of AT and RH were observed between vertical levels. The upper leaf canopy greatly reduced WS, and at a height of about 14 m above the ground it was close to zero. The highest diurnal [CO2] maximum and variations occurred at 1 m above the ground, and the lowest above the forest. In good light conditions in the forest, the entire leaf canopy (overstorey and understorey canopy) is a large sink of CO2. At night the forest stand is a source of CO2, the largest internal source being the soil and forest floor. 相似文献
116.
The greening of the upper part of the outerAllium cepa L. bulb scales, in particular along the vascular regions, is limited to the hypodermal cells in which typical leucoplasts are transformed to normal and functional chloroplasts. This process is light dependent and cannot afterwards be reversed or modified by darkness. The changes in fine structure are described and briefly discussed.Dedicated to Prof. DrLothar Geitler on the occasion of his 90th birthday and 55 years after the publication of his Grundriß der Cytologie. 相似文献
117.
118.
In the course of three years' investigations (1983–1986) of Lake Volvi, N Greece, 62 species and varieties of chlorococcal algae and 6 species of ulotrichal algae (Chlorophyceae) were found. Although chlorophytes form the largest group of the phytoplankton assemblages of the lake, their biomass is relatively small or even negligeable in some periods of the year in comparison with domination cyanophytes, diatoms and cryptophytes. Morphological variation of diagnostic features is described and documented by original drawings in 53 taxa. 相似文献
119.
František Krahulec 《Folia Geobotanica》1990,25(4):337-347
The montaneNardus-rich acidophilous meadows occurring in the Krkono?e and W. Carpathians Mts. were evaluated. They are classified intoNardo-Agrostion tenuis Sillinger 1933. Five associations were distinguished:Sileno-Nardetum, Homogyno-Nardetum, Hieracio Lachenalii-Nardetum, Phleo alpini-Nardetum, andRanunculo nemorosi-Nardetum, the first occuring in the Krkono?e Mts., the others in the W. Carpathians. 相似文献
120.
Agents known to influence Ca2+ homeostasis affected significantly the vegetative growth and starvation-induced conidiation ofTrichoderma viride. Ca2+ in millimolar concentrations stimulated both growth and conidiation; a Ca2+ deprivation of the fungus by the chelation of extracellular Ca2+ (not Mg2+ or divalent trace metals) with EGTA (ethyleneglycolbis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) restricted both the
vegetative growth rate and starvation-induced conidiation. Both processes were affected by either Ca2+ or EGTA with different efficiencies. Divalent cations (Sr2+, Ba2+, Co2+, Ni2+, Mg2+, Cd2+, Cu2+, Mn2+) and La3+ (inorganic Ca2+ blockers) in millimolar concentrations exerted complex (stimulatory, inhibitory, or biphasic) effects on growth and conidiation.
In general, their effects on the two processes were mutually different either qualitatively, or quantitatively, or both. Organic
Ca2+ antagonists (verapamil and dihydropyridines) inhibited the vegetative growth. The results show that Ca2+ is required for vegetative growth and conidiation, and that different Ca2+-dependent mechanisms may be involved in the two processes. Divalent cations could serve as a tool for investigating the relationship
between growth and conidiation. 相似文献