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1.
Effects of light quality on the chloroplastic ultrastructure and photosynthetic characteristics of cucumber seedlings 总被引:4,自引:0,他引:4
To understand how light quality influences plant photosynthesis, we investigated chloroplastic ultrastructure, chlorophyll fluorescence and photosynthetic parameters, Rubisco and chlorophyll content and photosynthesis-related genes expression in cucumber seedlings exposed to different light qualities: white, red, blue, yellow and green lights with the same photosynthetic photon flux density of 100 μmol m?2 s?1. The results revealed that plant growth, CO2 assimilation rate and chlorophyll content were significantly reduced in the seedlings grown under red, blue, yellow and green lights as compared with those grown under white light, but each monochromatic light played its special role in regulating plant morphogenesis and photosynthesis. Seedling leaves were thickened and slightly curled; Rubisco biosynthesis, expression of the rca, rbcS and rbcL, the maximal photochemical efficiency of PSII (Fv/Fm) and quantum yield of PSII electron transport (ФPSII) were all increased in seedlings grown under blue light as compared with those grown under white light. Furthermore, the photosynthetic rate of seedlings grown under blue light was significantly increased, and leaf number and chlorophyll content of seedlings grown under red light were increased as compared with those exposed to other monochromatic lights. On the contrary, the seedlings grown under yellow and green lights were dwarf with the new leaves etiolated. Moreover, photosynthesis, Rubisco biosynthesis and relative gene expression were greatly decreased in seedlings grown under yellow and green light, but chloroplast structural features were less influenced. Interestingly, the Fv/Fm, ФPSII value and chlorophyll content of the seedlings grown under green light were much higher than those grown under yellow light. 相似文献
2.
In saturating irradiances of red light, photosynthesis of Laminaria saccharina (L.) Lamouroux was stimulated by low irradiances of continuous blue light only when the supply of dissolved inorganic carbon (DIC) was limiting. The degree of this stimulation was inversely proportional to the logarithm of the concentration of free CO2, whether this was adjusted by varying the total DIC or the pH at a given DIC concentration. The final pH reached in a closed system was higher in blue light than in red light. Both acetazolamide and ethoxyzolamide suppressed the responses to blue light almost completely, but reduced photosynthesis in red light by only 30%. Buffering the pH of the seawater also suppressed the stimulation of photosynthesis by blue light without affecting the photosynthetic rate in red light. The transient stimulation of O2 evolution by a blue light pulse was not accompanied by a corresponding increase in CO2 consumption. These observations could be explained if, in analogy to the mechanism proposed for Ectocarpus (Schmid, Mills & Dring 1996, Plant Cell and Environment 19,373–382, this issue, accompanying paper), photosynthesis was supported by a blue-light-activated release of CO2 from an internal store. We suggest that the store is located in the vacuoles of the cortical tissue of the blades. The main photosynthetic tissue, however, is in the overlying meristoderm, and blue-light-activated mobilization of the store could stimulate O2 evolution only if periplasmic carbonic anhydrase was available to facilitate CO2 uptake from the cortex. 相似文献
3.
Effects of light intensity and oxygen on photosynthesis and translocation in sugar beet 总被引:14,自引:11,他引:3
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The mass transfer rate of 14C-sucrose translocation from sugar beet (Beta vulgaris, L.) leaves was measured over a range of net photosynthesis rates from 0 to 60 milligrams of CO2 decimeters−2 hour−1 under varying conditions of light intensity, CO2 concentration, and O2 concentration. The resulting rate of translocation of labeled photosynthate into total sink tissue was a linear function (slope = 0.18) of the net photosynthesis rate of the source leaf regardless of light intensity (2000, 3700, or 7200 foot-candles), O2 concentration (21% or 1% O2), or CO2 concentration (900 microliters/liter of CO2 to compensation concentration). These data support the theory that the mass transfer rate of translocation under conditions of sufficient sink demand is limited by the net photosynthesis rate or more specifically by sucrose synthesis and this limitation is independent of light intensity per se. The rate of translocation was not saturated even at net photosynthesis rates four times greater than the rate occurring at 300 microliters/liter of CO2, 21% O2, and saturating light intensity. 相似文献
4.
Redox Processes in the Blue Light Response of Guard Cell Protoplasts of Commelina communis L 总被引:7,自引:4,他引:3
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Guard cell protoplasts from Commelina communis L. illuminated with red light responded to a blue light pulse by an H+ extrusion which lasted for about 10 minutes. This proton extrusion was accompanied by an O2 uptake with a 4H+ to O2 ratio. The response to blue light was nil in darkness without a preillumination period of red light and increased with the duration of the red light illumination until about 40 minutes. However, acidification in response to a pulse of blue light was obtained in darkness when external NADH (1 millimolar) was added to the incubation medium, suggesting that redox equivalents necessary for the expression of the response to blue light in darkness may be supplied via red light. In accordance with this hypothesis, the photosystem II inhibitor 3-(3,4-dichlorophenyl)-1, 1-dimethylurea (10 micromolar) decreased the acidification in response to blue light more efficiently when it was added before red light illumination than before the blue light pulse. In the presence of hexacyanoferrate, the acidification in response to a blue light pulse was partly inhibited (53% of control), suggesting a competition for reducing power between ferricyanide reduction and the response to blue light. 相似文献
5.
The effect of blue and red light on the adaptation to low CO2 conditions was studied in high-CO2 grown cultures of Chlorella Pyrenoidosa (82T) and Chlamydomonas reinhardtii(137+) by measuring O2 exchange under various inorganic carbon (Ci) concentrations. At equal photosynthetic photon flux density (PPFD), blue light was more favourable for adaptation in both species, compared to red light. The difference in photosynthetic oxygen evolution between cells adapted to low Ciunder blue and red light was more pronounced when oxygen evolution was measured under low Ci compared to high Ci conditions. The effect of light quality on adaptation remained for several hours. The different effects caused by blue and red light was observed in C. pyrenoidosa over a wide range of PPFD with increasing differences at increasing PPFD. The maximal difference was obtained at a PPFD above 1 500 μmol m?2s?1. We found no difference in the extracellular carbonic anhydrase activity between blue- and red light adapted cells. The light quality effect recorded under Ci-limiting conditions in C. reinhardtii cells adapted to air, was only 37% less when instead of pure blue light red light containing 12.5% of blue light (similar PPFD as blue light) was used during adaptation to low carbon. This indicates that in addition to affecting photosynthesis, blue light affected a sensory system involved in algal adaptation to low Ci conditions. Since the affinity for Ci of C. Pyrenoidosa and C. reinhardtii cells adapted to air under blue light was higher than that of cells adapted under red light, we suggest that induction of some component(s) of the Ci accumulating mechanism is regulated by the light quality. 相似文献
6.
CO2 exchange were measured on pea seedlings (Pisum sativum L. var. Bördi) cultivated from seeds imbibed either in water (C-plants) or in gibberellic acid (GA3) at the concentration of 25 g/1 (GA-plants), and then grown under 17 W/m2 blue light (B-plants) or 11 W/m2 red light (R-plants).When measured under the same light conditions as during growth the net photosynthesis (APS) rate in B-plants was about twice higher than that in R-plants. Dark respiration (DR) rate was 70% higher in B- than in R-plants. Red light retarded the development of photosynthetic activity, but GA3 suppressed this effect. The hormone enhanced net photosynthesis and dark respiration to the same extent.When measured under saturating white light net photosynthesis rate of C-plants was also two times higher in B-plants than in R-plants. Growth conditions had only a slight effect on the APS of GA-plants under white light. APS rates of GA-plants grown under red light were higher under white light than those of C-plants, but lower than those of plants grown under blue light.We assume that blue light induced formation of plants that were adapted to higher light intensity: red light had an opposite effect, whereas gibberellic acid induced formation of plants that were adapted to medium light intensity. 相似文献
7.
Effect of light quality on the organization of photosynthetic electron transport chain of pea seedlings 总被引:7,自引:0,他引:7
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The activity of NADP and O2 photoreduction by water is essentially higher in chloroplasts isolated from pea seedlings (Pisum sativum L.) grown under blue light as compared with that from plants grown under red light. In contrast, the photoreduction of NADP and O2 with photosystem I only is practically the same or even lower in chloroplasts isolated from plants grown under blue light. The addition of plastocyanin does not affect the rate or the extent of NADP photoreduction by water in the chloroplasts isolated from plants grown under blue light, whereas it sharply activates NADP reduction in the chloroplasts isolated from plants grown under red light. The extent of the light-induced oxidation of cytochrome f is appreciably higher in chloroplasts isolated from plants grown under blue light. Cytochrome b559 plays the predominant role in the oxidoreductive reactions of these chloroplasts. Furthermore, the fluorescence measurements indicate more effective transfer of excitation energy from chlorophyll to the photosystem II reaction center in chloroplasts isolated from plants grown under blue light. 相似文献
8.
Blue light induced stomatal opening has been studied by applying a short pulse (~5 to 60 s) of blue light to a background of saturating photosynthetic red photons, but little is known about steady-state stomatal responses. Here we report stomatal responses to blue light at high and low CO2 concentrations. Steady-state stomatal conductance (gs) of C3 plants increased asymptotically with increasing blue light to a maximum at 20% blue (120 μmol m−2 s−1). This response was consistent from 200 to 800 μmol mol−1 atmospheric CO2 (Ca). In contrast, blue light induced only a transient stomatal opening (~5 min) in C4 species above a Ca of 400 μmol mol−1. Steady-state gs of C4 plants generally decreased with increasing blue intensity. The net photosynthetic rate of all species decreased above 20% blue because blue photons have lower quantum yield (moles carbon fixed per mole photons absorbed) than red photons. Our findings indicate that photosynthesis, rather than a blue light signal, plays a dominant role in stomatal regulation in C4 species. Additionally, we found that blue light affected only stomata on the illuminated side of the leaf. Contrary to widely held belief, the blue light-induced stomatal opening minimally enhanced photosynthesis and consistently decreased water use efficiency. 相似文献
9.
Interactions of blue light and inorganic carbon supply in the control of light-saturated photosynthesis in brown algae 总被引:3,自引:2,他引:1
Photosynthetic capacities of five species of brown algae in red light were found to be strongly limited by the inorganic carbon supply of natural sea water. Under these conditions, pH 8·2 and dissolved inorganic carbon concentration (DIG) of 2·1 mol m?3, a short pulse of blue light was found to increase the subsequent rate of photosynthesis in saturating red light. The degree of blue light stimulation varied between species, ranging from an increase of over 200% of the original rate in Colpomenia peregrins to only 10% in Dictyota dichotoma. Increasing the DIG concentration of sea water by bicarbonate addition resulted in carbon saturation of photosynthesis in all five species. Blue light stimulation was greatly reduced at these higher DIG concentrations. The response in Laminaria digitata was examined in more detail by manipulation of pH and DIG to produce solutions with different concentrations of dissolved CO2. At a CO2 concentration typical of normal sea water (12·4 mmol m?3), blue light treatment increased photosynthetic rate by approximately 50%. Blue light stimulation was increased to over 150% at CO2 concentrations below that of sea water, whereas at concentrations above that of sea water, the effect was diminished. Therefore, the effect of blue light on photosynthetic capacity appears to involve an increase in the rate of supply of carbon dioxide to the plant. 相似文献
10.
《Plant Physiology and Biochemistry》2000,38(9):717-725
In the present work, the aim was to study the combined effects of high irradiance (about 1 000 μmol·m–2·s–1) on the effects of O3 (150 nL·L–1 for 2 h) on the photosynthetic process of primary pinto (Phaseolus vulgaris L.) leaves. The CO2 assimilation rate significantly decreased in high light and/or O3-treated leaves, as did the stomatal conductance. The present work shows that changes occur in photosynthesis-related parameters due to light stress. Photoinhibition was detected as a decrease in the Fv/Fm ratio. This indicates that the light treatment considerably exceeded the photoprotective capacity and resulted in significant photon damage. Moreover O3 fumigation alone determined an impairment of the photosynthetic process, that in this case is related to the dark reactions of photosynthesis as also showed by the strong increase in (1-qP). The data presented in this paper illustrate the complexity of photosynthetic response to high light intensities and ozone, which are two stress factors that often occur simultaneously under natural conditions. High light can modify the reaction of leaves to ozone treatment by reducing the chloroplastic electron transport rate and the quantum yield for PSII photochemistry. Thus, high light seems to enhance the detrimental effects of ozone on photosynthesis. 相似文献
11.
R. Schmid 《Plant, cell & environment》1998,21(5):523-529
Pulses of blue light cause stimulation of red light saturated photosynthesis in Ectocarpus siliculosus, because blue light activates the operation of a pathway for inorganic carbon (Ci) acquisition by inducing the mobilization of CO2 from an intermediate metabolite. In the absence of exogenous Ci, photosynthetic rates roughly equal those of CO2 release by respiration. In seawater of pH 9·5 (2·3 mol m–3 total Ci, but concentrations of free CO2 below 0·2 mmol m–3), photosynthesis was clearly above these rates, although they were only ≈ 30% of those in normal seawater (≈ pH 8). The degree and the time course of the stimulations of photosynthesis by pulses of blue light were unaltered at high pH. Essentially the same characteristics were found after buffering or in the presence of acetazolamide, an inhibitor of extracellular carbonic anhydrase activity. Therefore, it is concluded that Ectocarpus is able to directly take up HCO3– in addition to CO2 (uptake of CO32– cannot be excluded). The dependence of photosynthesis on Ci at pH 9·5 was biphasic, with Ci below 0·2 mol m–3 having no effect at all. In Ci-free seawater, the shapes of the stimulations after blue light pulses differed for pH 6, pH 8 and pH 9·5. At low pH, only the fast peak (maximum ≈ 5 min after blue light) was detected, whereas at high pH mainly the slow peak (maximum ≈ 20 min after blue light) was observed. At the intermediate pH 8, both peaks were present. As inhibition of total carbonic anhydrase by ethoxyzolamide brought out the fast peak of the stimulations at pH 9·5 it is concluded that the fast component was due to a transient disequilibrium of an intracellular pool of Ci which, after blue light, was fed by CO2 released from the postulated storage intermediate. 相似文献
12.
Control of the Photosynthetic Apparatus of Acetabularia mediterranea by Blue Light : Analysis by Light-Saturation Curves 总被引:1,自引:0,他引:1
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During growth, Acetabularia mediterranea requires the action of blue light to maintain high rates of photosynthesis. In the present study, blue light-dependent alterations of the photosynthetic apparatus, which can be detected by analysis of light-saturation curves and by measurements of partial reactions of the photosynthetic electron transport chain, are described. Light-saturation curves of photosynthesis in vivo were measured with a new closed oxygen electrode system after culture of Acetabularia in continuous red or blue light. These curves were compared to those of 2,6-dichlorophenol-indophenol reduction by isolated chloroplast membranes. The analysis lead to the following statements: (a) only one reaction limits electron transport rates in vitro (dichlorophenol-indophenol reduction) at all light intensities irrespective of the light quality during growth, and (b) the limiting step is light driven and located in the reaction center of photosystem II. Presumably, this same reaction determines the flow of electrons under low light intensities in vivo in cells from white, blue, and red light. In addition to photosynthesis, the rates of dark respiration changed due to the action of blue light. Concomitantly, the light compensation point of apparent photosynthesis was shifted during monochromatic irradiations. 相似文献
13.
Rates of net photosynthesis and respiration were determined for Pithophora oedogonia (Mont.) Wittr. acclimatized to 56 combinations of light (7–1200 μE m?2 s?1) and temperature (5–35°C). Conditions for maximum net photosynthesis were estimated to be 26°C and 970 μE m?2 s?1. The rate of net photosyntheses varied considerably with temperature, with the maximum measured value (9.67 mg O2 h?1 g dry wt.?1) occurring at 25°C. Respiration rate increased with temperature and the light received just prior to measurement. The maximum respiration rate (7.05 mg O2 g?1 h?1) occurred at 30°C and 1200 μE m?2 s?1. Exposure of Pithophora to light levels of 600 or 1200 μE m?2 s?1 prior to determination of the respiration rate resulted in significantly elevated levels of oxygen consumption at temperatures ≥ 15°C. The relationship between light, temperature and photosynthesis and respiration were summarized as three-dimensional response surfaces. 相似文献
14.
Md. Abdullahil Baque Eun-Joo Hahn Kee-Yoeup Paek 《In vitro cellular & developmental biology. Plant》2010,46(1):71-80
An efficient protocol for adventitious root induction from leaf explants of Morinda citrifolia treated with different concentrations of indole-3-butyric acid (IBA) and α-naphthaleneacetic acid (NAA) was established in
relation to physiological process changes during adventitious root induction under different light sources (fluorescent, red,
blue, red + blue, and far-red). Among the different concentrations of IBA and NAA, 1.0 mg l−1 IBA was proven as the best auxin source for adventitious root induction under fluorescent light. Higher concentrations of
IBA and NAA trigger callus formation in both light and dark conditions. Maximum numbers of adventitious roots were induced
under red light (26) followed by blue light (22) and the lowest under far-red light (6). In contrast, numerous callus formations
were induced by red + blue followed by red and blue, while the highest root length (1.66 cm) with negligible callusing was
observed under fluorescent light. Catalase and guaicacol peroxidase activities were highest under red light followed by fluorescent
light and the lowest under red + blue light, but superoxide dismutase activity was not significantly influenced by different
light sources. Ascorbate peroxidase played an important role in detoxification of the harmful effects of hydrogen peroxide
(H2O2). Under fluorescent light, significantly lower accumulation of H2O2 was observed. Accumulation of H2O2 in the induced root under different light showed a positive correlation with peroxidation of lipids and was observed higher
under far-red followed by red + blue and blue light. 相似文献
15.
N. ROTH-BEJERANO 《Physiologia plantarum》1980,50(3):326-330
The elongation of hypocotyls excised from de-etiolated seedlings of beans (Phaseolus vulgaris L. cv. British Wax) is inhibited by light, blue and red irradiations being equally effective. Conditions which decrease chlorophyll fluorescence, such as CO2-free air, abolish the inhibitory effect of blue irradiation and enhance the inhibition by red light. Conversely, conditions which increase chlorophyll fluorescence, such as a N2 atmosphere or irradiation through a chlorophyll filter, abolish the inhibitory effect of red light and enhance the inhibition by blue irradiation. The inhibitory effect of blue light is reversible by red irradiation under increased fluorescence as well as by far red. We propose that the chlorophyll fluorescence excited by blue and red irradiations in λF > 660 nm and λF > 720 nm, respectively, is responsible for the inhibitory effect of blue light and the reduction of the inhibitory effect of non fluorescing red light. Both red and blue wavelengths seem, therefore, to control hypocotyl elongation through phytochrome. 相似文献
16.
Changes in Chlorophyll a/b Ratio and Products of CO(2) Fixation by Algae Grown in Blue or Red Light
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Chlamydomonas and Chlorella were grown for 10 days in white light. 955 μw/cm2 blue light (400-500 mμ) or 685 μw/cm2 red light (above 600 mμ). Rates of growth in blue or red light were initially slow, but increased over a period of 5 days until normal growth rates were reestablished. During this adaptation period in blue light, total chlorophyll per volume of algae increased 20% while the chlorophyll a/b ratio decreased. In red light no change was observed in the total amount of chlorophyll or in the chlorophyll a/b ratio. After adaptation to growth in blue light and upon exposure to 14CO2 with either blue or white light for 3 to 10 minutes, 30 to 36% of the total soluble fixed 14C accumulated in glycolate-14C which was the major product. However, with 1 minute experiments, it was shown that phosphate esters of the photosynthetic carbon cycle were labeled before the glycolate. Glycolate accumulation by algae grown in blue light occurred even at low light intensity. After growth of the algae in red light, 14C accumulated in malate, aspartate, glutamate and alanine, whereas glycolate contained less than 3% of the soluble 14C fraction. 相似文献
17.
Flavonoid synthesis in cell suspension cultures of parsley (Petroselinum hortense Hoffm.) occurs only after irradiation with ultraviolet light (UV), mainly from the UV-B (280–320 nm) spectral range. However, it is also controlled by phytochrome. A Pfr/Ptot ratio of approximately 20% is sufficient for a maximum phytochrome response as induced by pulse irradiation. Continuous red and far red light, as well as blue light, given after UV, are more effective than pulse irradiations. The response to blue light is considerably greater than that to red and far red light. Continuous red and blue light treatments can be substituted for by multiple pulses and can thus probably be ascribed to a multible induction effect. Continuous irradiations with red, far red and blue light also increase the UV-induced flavonoid synthesis if given before UV. The data indicate that besides phytochrome a separate blue light photoreceptor is involved in the regulation of the UV-induced flavonoid synthesis. This blue light receptor seems to require the presence of Pfr in order to be fully effective.Abbreviations HIR
high irradiance response
- Pfr
far red absorhing form of phytochrome
- Ptet
total phytochrome
- UV
ultraviolet light 相似文献
18.
Evaluation of the light/dark C assay of photorespiration: tobacco leaf disk studies with glycidate and glyoxylate
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Chollet R 《Plant physiology》1978,61(6):929-932
Preincubation of illuminated tobacco (Nicotiana tabacum L.) leaf disks in glycidate (2,3-epoxypropionate) or glyoxylate inhibited photorespiration by about 40% as determined by the ratio of 14CO2 evolved into CO2-free air in light and in darkness. However, under identical preincubation conditions used for the light/dark 14C assays, the compounds failed to reduce photorespiration or stimulate net photosynthesis in tobacco leaf disks based on other CO2 exchange parameters, including the CO2 compensation concentration in 21% O2, the inhibitory effect of 21% O2 on net photosynthesis in 360 microliters per liter of CO2 and the rate of net photosynthetic 14CO2 uptake in air.
The effects of both glycidate and glyoxylate on the 14C assay are inconsistent with other measures of photorespiratory CO2 exchange in tobacco leaf disks, and thus these data question the validity of the light to dark ratio of 14CO2 efflux as an assay for relative rates of photorespiration (Zelitch 1968, Plant Physiol 43: 1829-1837). The results of this study specifically indicate that neither glycidate nor glyoxylate reduces photorespiration or stimulates net photosynthesis by tobacco leaf disks under physiological conditions of pO2 and pCO2, contrary to previous reports.
相似文献19.
Photosynthetic microbial fuel cells (PMFCs) are devices that convert chemical energy into the form of electricity through the catalytic activity of photosynthetic microorganisms. Power densities produced by the photosynthetic microalgae are greatly dependant on light sources and light intensities because these two factors can affect the chlorophyll formation, photosynthesis processes and stomata opening in the microalgae cells. In the present study, Chlamydomonas reinhardtii transformation F5 was used as biocatalyst in photo microbial fuel cells (PMFCs) and were illuminated with monochromatic blue and red LED lights at various light intensities (100, 300, 600 and 900 lx), respectively. The kinetic analysis was successfully employed to describe the intracellular and extracellular electron transfer mechanism of the cells. The results demonstrate that the performance of PMFCs increased in terms of maximum power density and exchange current density (io) with the tendency of decreasing in internal resistance (Rint) and over potential (η) values as increasing monochromatic blue and red LED light intensities. However the PMFCs performed better under red LED light as compared to operating under blue LED light. The maximum power density can reach 12.947 mW m−2, which could be a potential micro-power supply. 相似文献
20.
V. B. Borodin 《Russian Journal of Plant Physiology》2013,60(3):420-430
The effect of storage of the unicellular green alga Chlamydomonas reinhardtii (strain 137+) in the pelleted state in darkness on ice (0.2–0.5°C) (further simply “SPDI-treatment”) on its photosynthetic and respiratory activities was studied. To this end, the steady-state rates of O2 exchange in darkness (dark respiration) and under saturating light (apparent photosynthesis) as well as the induction periods (IP) of apparent photosynthesis were measured at 25°C in the SPDI-untreated and SPDI-treated for the period from ~0.5 to ~30 h algal cells. In contrast to expectations, the SPDI-treatment consistently affected the rate and IP of photosynthesis depending on the physiological state of C. reinhardtii. Dark respiration was affected by the SPDI-treatment as well. However, in absolute values the respiratory changes were much less than the photosynthetic ones, and they were insufficiently reproducible. The SPDI-treatment affected photosynthesis most significantly in high-CO2-grown cells (cells grown at 5% CO2 in white light). The rate of photosynthesis in these cells declined quasi-exponentially as a function of time during the SPDI-treatment with a t 1/2 ~1.5 h and finally became by about 60% lower than that before the SPDI-treatment. This decline of photosynthesis was accompanied by continuous and essential increase in the photosynthetic IP. The SPDI-induced photosynthetic changes in high-CO2-grown cells resulted from the firm disfunction of the photosynthetic apparatus. After switch from growth at 5% CO2 in white light to growth at ~0.03% CO2 (air) in white, blue, or red light, the alga gradually transited to a physiological state, in which the negative effects of the SPDI-treatment on the rate and IP of photosynthesis became weak and absent, respectively. Remarkably, this transition was faster in blue (≤5 h) than in white and red light (>10 h). Similar changes in the response of the alga to the SPDI-treatment occurred when high-CO2-grown cells (5% CO2, white light, 26°C) were incubated in darkness (air, 24–26°C) for 20–25 h. The results of study were analyzed in the light of literature data relating to the effects of CO2 concentration, darkness, and light quality on carbohydrates in plant organisms. The analysis led to suggestion that there is connection between the negative effect of the SPDI-treatment on C. reinhardtii and nonstructural carbohydrates presented in the alga: the more carbohydrates contain the alga, the more extensive inactivation of the photosynthetic apparatus occurs in it during its storage in the dense (pelleted) state in darkness on ice. 相似文献