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1.
M. T. Grzesiak A. Rzepka T. Hura S. Grzesiak K. Hura W. Filek A. Skoczowski 《Photosynthetica》2007,45(4):606-611
An influence of soil drought (7 or 14 d) and 7 d recovery on changes of leaf fluorescence excitation spectra at wavelengths
of 450, 520, 690, and 740 nm (F450, F520, F690, F740) for drought resistant and sensitive genotypes of triticale and maize was compared. In non-stressed plants the differences
between maize and triticale were observed for F450 and F520, but not for F690 and F740. Drought caused the increase in F450, F520, and F690 and this increase was more distinct for drought sensitive genotypes. After re-hydration, chlorophyll fluorescence mostly
recovered to values of control plants. Drought caused significant increase in F690/F740 but not in F450/F690 and F450/F520. For triticale, highest increase in F690/F740 was observed in the 4th and 7th leaves of resistant genotype and contrarily in maize for the sensitive one. After recovery, the F450/F520, F450/F690, and F690/F740 ratios mostly returned to values of control plants. 相似文献
2.
Malgorzata Brindell Iwona Stawoska Justyna Supel Andrzej Skoczowski Grazyna Stochel Rudi van Eldik 《Journal of biological inorganic chemistry》2008,13(6):909-918
A systematic study of the reduction of (ImH)[trans-RuCl(4)(dmso)(Im)] (NAMI-A; dmso is dimethyl sulfoxide, Im is imidazole), a promising antimetastasing agent, by L: -ascorbic acid under physiological conditions is reported. Under blood plasma conditions (pH 7.4, 0.1-0.15 M NaCl , 37 degrees C) the rapid reduction of trans-[Ru(III)Cl(4)(dmso)(Im)](-) results in the formation of trans-[Ru(II)Cl(4)(dmso)(Im)](2-) within seconds, and is followed by successive dissociation of the chloride ligands, whereas neither dmso nor imidazole ligands are released during the reaction. Under our experimental conditions, the formation of the ascorbate dianion is the rate-determining step, and once it has formed it reacts rapidly with NAMI-A. Moreover, the NAMI-A complex is very unstable at physiological pH (7.4); therefore, the hydrolysis of NAMI-A cannot be excluded as a competing reaction. During hydrolysis, aquated derivatives via stepwise dissociation of chloride and dmso ligands are formed, and most of these species have a higher redox potential and are expected to be even more easily reduced by ascorbic acid. Thus, it is very likely that the reduced form of NAMI-A or the reduction products of its hydrolytic derivatives react with albumin. The reaction of reduced NAMI-A with human serum albumin leads to the formation of stable adducts, with a binding efficiency very similar to that of the parent complex, viz., 3.2 +/- 0.3 and 4.0 +/- 0.4 mol of Ru(II) and Ru(III) per mole of albumin, respectively, however with a significantly higher reactivity. 相似文献
3.
Iwona Żur Andrzej Skoczowski Sebastian Pieńkowski Franciszek Dubert 《Acta Physiologiae Plantarum》2002,24(1):11-17
The uptake rate of 14C-labelled sucrose, myo-inositol and PC was studied in callus cultures of two oilseed rape cultivars, characterized by different in vitro regeneration ability. Transfer of calli onto regeneration stimulating medium resulted in changes of examined substances uptake
rate, which were depended on tissue morphogenic potential. Non-regenerating calli of both cultivars increased uptake rate
of sucrose whereas changes in incorporation of other compounds were under genome control. Significant increase of uptake rate
of all tested compounds was observed as result of organogenesis initiation. Such differences, in the responses of organogenic
and non-organogenic tissue indicate that this parameter could be useful as marker of organogenesis
A correlation was observed between the rate of sucrose uptake and its concentration in the medium, which suggests an advantage
to passive transport through the callus cell membrane. Lack of such correlation in the case of other labels indicates that
this processes are selective and under cell control. 相似文献
4.
Żur Iwona Skoczowski Andrzej Niemczyk Elżbieta Dubert Franciszek 《Acta Physiologiae Plantarum》2002,24(1):3-10
Changes in the membrane lipid and sterols content and composition were studied during induction and differentiation in callus
cultures of Brassica napus var. oleifera. Callus induction was associated with an increase of DGDG content, significant changes in fatty acids composition of all
lipid fractions and increased degree of lipid unsaturation. The membrane lipid composition of tissue at different degrees
of differentiation was found to vary significantly, particularly two weeks after transfer of callus to regeneration medium.
The main differences concerned the content and composition of galactolipids. Curiously in many cases, these differences declined
during subsequent culture, in spite of the morphogenesis process which was in progress. Another result of differentiation
was the change in free sterol composition: in shoot regenerating calli the content of stigmasterol had rose whereas the accumulation
of campesterol decreased. Even though observed changes in membrane properties may not play a role in morphogenesis they are
nevertheless useful as developmental markers and can be invaluable in understanding biochemical basis of morphogenesis. 相似文献
5.
6.
Photosynthetica - Seedlings of spring barley, meadow fescue, and winter rape were fumigated with 180 μg kg−1 of ozone for 12 d, and effect of O3 on photosynthesis and cell membrane... 相似文献
7.
Diana Saja Magdalena Rys Iwona Stawoska Andrzej Skoczowski 《Acta Physiologiae Plantarum》2016,38(7):168
Tribenuron-methyl is the active substance of the herbicide used for weed control in crops. The aim of this study was to investigate differences in the metabolic response of seeds, seedlings and leaves of Centaurea cyanus L., depending on the degree of resistance to tribenuron-methyl. Changes in the values of selected biochemical and physiological parameters (germination index, chemical composition, photochemical efficiency of photosystem II and the emission spectra of blue-green fluorescence) presented herein make it possible to determine the differences between cornflower biotypes with various types of resistance to the tested herbicide. Moreover, differences in the chemical composition of dry seeds between biotypes susceptible and resistant to tribenuron-methyl were observed before using the herbicide. The degree of resistance to the herbicide—resistant or susceptible, but not the types of this resistance-mutational or metabolic, can be distinguished on the basis of the presented parameters. These findings allow for early diagnosis of the resistance of cornflower to tribenuron-methyl. Additionally, we suggest that the described parameters might be used as physiochemical markers for early estimation of weed resistance to various types of herbicide. The presented conclusions are especially important for agricultural practice. 相似文献
8.
Although the fern Platycerium bifurcatum is popular among the producers of ornamental plants, it is a species of relatively poorly known physiology. Studies concerning the impact of the red/far-red (R/FR) ratio on photomorphogenesis refer primarily to spermatophytes. However, quite different phytochrome response mechanism functions in ferns, involving the localization of physiologically active form of phytochrome in the cytoplasm, without translocation to the nucleus. This work determined the reaction of young fern sporotrophophylls to the change of the R/FR ratio and investigated sporophyte ontogeny in various spectral light composition using non-destructive testing methods. It has been shown that the development of morphogenic sporophyte depends on the R/FR ratio. At a high R/FR ratio, sporotrophophylls showed a slower growth compared to those growing at a low value. A high R/FR value resulted in lower photochemical performance of PSII and adverse changes in the functioning of the acceptor portion of the PSII reaction center, while the PSII vitality analysis indicated the positive effect of simulated shadow. The value of the R/FR ratio did not affect the intensity of blue-green leaf fluorescence. However, the fluorescence intensity of red and far-red was significantly higher in plants growing at higher R/FR values. The analysis of leaf optical properties indicated higher concentrations of carotenoids and anthocyanins in the leaves of plants grown under the lower R/FR ratio. Determining the effect of spectral light composition on the physiology of this species may be useful for plant breeders and for the protection of these epiphytes in natural habitats. 相似文献
9.
Influence of drought (D) on changes of leaf water potential (Ψ) and parameters of gas exchange in D-resistant and D-sensitive
genotypes of triticale and maize was compared. Soil D (from −0.01 to −2.45 MPa) was simulated by mannitol solutions. At −0.013
MPa significant differences in Ψ, net photosynthetic rate (P
N), transpiration rate (E), stomatal conductance (g
s), and internal CO2 concentration (C
i) of D-resistant and D-sensitive triticale and maize genotypes were not found. Together with the increase in concentration
of the mannitol solution the impact of D on E and g
s for D-sensitive genotypes (CHD-12, Ankora) became lower than for the D-resistant ones (CHD-247, Tina). Inversely, impact
of D on Ψ was higher in D-sensitive than D-resistant genotypes. From 1 to 3 d of D, a higher decrease in P
N was observed in D-resistant genotypes than in the D-sensitive ones. Under prolonged D (5–14 d) and simultaneous more severe
D the decrease in P
N was lower in D-resistant than in D-sensitive genotypes. Changes in Ψ, P
N, E, and g
s caused by D in genotypes differing in the drought susceptibility were similar for triticale and maize. Compared to control
plants, increase of C
i was different for triticale and maize genotypes. Hence one of the physiological reasons of different susceptibility to D
between sensitive and resistant genotypes is more efficient protection of tissue water status in resistant genotypes reflected
in higher decrease in g
s and limiting E compared to the sensitive ones. Other reason, observed in D-resistant genotypes during the recovery from D-stress, was more
efficient removal of detrimental effects of D. 相似文献
10.
Anna Janeczko Katarzyna Hura Andrzej Skoczowski Iwona Idzik Jolanta Biesaga-Kościelniak Elżbieta Niemczyk 《Acta Physiologiae Plantarum》2009,31(1):71-79
The aim of this experiment was to study the effect of 24-epibrassinolide (BR27) on fatty acids composition and sugar content in winter oilseed rape callus cultured at 20 and 5°C. Studies have showed that
BR27 action is highly temperature-dependent. The increase in sugar content (sucrose, glucose and fructose) by BR27 in concentration 100 nM was observed only in calli cultured at 20°C. At 5°C, quite the opposite effect of BR27 action was observed; where cold increased the sugar content, BR27 decreased it. BR27 at 20°C had a similar effect on the fatty acid composition of phospholipids (PL) as the cold in the process of frost hardening
of oilseed rape calli. BR27 decreased the 16:0, 18:1 and 18:2 and increased the 18:3 fatty acid content. At 5°C, BR27 (100 nM) generally did not influence the fatty acid composition of PL. In case of digalactosyl diacylglycerols and monogalactosyl
diacylglycerols, the influence of BR27 on the fatty acid composition is ambiguous but still depends on temperature. 相似文献