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102. Increased water supply promotes photosynthesis, C/N ratio, and plantamajoside accumulation in the medicinal plant Plantago depressa Willd
- Creator:
- Li, Z., Bai, W., Zhang, L., and Li, L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- biomasa, chlorofyl, biomass, chlorophyll, změny klimatu, řízené prostředí, výměna plynu, fenolické sloučeniny, mezibuněčné koncentrace CO2, rychlost čisté fotosyntézy, stomatální vodivost, Plantago depressa, climate change, controlled environment, gas exchange, phenolic compounds, C/N ratio, intercellular CO2 concentration, net photosynthetic rate, plantamajoside, stomatal conductance, 2, and 581
- Language:
- Multiple languages
- Description:
- Anthropogenic activities are changing global precipitation regimes and result in many middle latitude arid and semiarid regions experiencing less precipitation and more extreme weather events. However, little is known about the response of active ingredient accumulation in the medicinal herb Plantago depressa Willd. Therefore, we carried out a greenhouse experiment in order to study effect of control (CK, normal water supply equal to 309 mm per four months), -30 (-WS) and +30% (+WS) of the control water supply on the photosynthesis (PN), C/N ratio, and plantamajoside accumulation in P. depressa. Our results showed that compared with the-WS and CK treatments, the +WS treatment significantly enhanced biomass, the C/N ratio, plantamajoside concentration, yield in shoots and roots, and PN, but declined the N concentration in shoots and roots. The plantamajoside concentration was positively correlated with PN, the soluble sugar content, and the C/N ratio, but negatively correlated with the N concentration. Our results suggested that, under experimental conditions, +WS increased the C/N ratio and promoted the plantamajoside accumulation of P. depressa., Z. Li, W. Bai, L. Zhang, L. Li., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
103. Induction of the photosystem 2 dark formation in etiolated leaves with the involvement of exogenous chlorophyllides
- Creator:
- Domanskiï, V. P. and Fradkin, L. I.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, delayed luminiscence, Hordeum vulgare, infiltration, NADPH, and reaction centre
- Language:
- Multiple languages
- Description:
- The delayed luminescence (DL) of photosystem 2 (PS2) after infiltration of 7-d-old etiolated barley leaves with chlorophyllides (Chlide) a or b followed by 2.5 h dark incubation was studied. Chlide a caused a very weak DL of PS2 just at the beginning of irradiation and the intensity of this DL was not higher when the infiltration medium contained 2 mM of NADPH. Chlide b was a somewhat more efficient inducer of PS2 formation in the dark and NADPH enhanced this efficiency 4.5 times though it did not affect the amount of esterified Chlides. The photoconversion of endogenous Pchlide led to a much higher intensity of the DL in comparison with the infiltration of Chlides, while the total amount of chlorophyll (Chl) formed was almost unchanged. The use of Chlide b together with the acetone extract from green leaves, devoid of pigments, resulted in the DL intensity comparable with that observed after Pchlide photoconversion followed by 2.5 h incubation in the dark. Dark formation of active PS2 in etiolated leaves was shown for the first time. Thus the dark formation of active PS2 may require Chl b, NADPH, and some unidentified water-soluble factor(s), synthesized in the dark after a short irradiation of etiolated leaves and inherent in green leaves. and V. P. Domanskiï, L.I. Fradkin.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
104. Influence of etherel and gibberellic acid on carbon metabolism, growth, and essential oil accumulation in spearmint (Mentha spicata)
- Creator:
- Singh, Preety, Srivastava, N. K., Mishra, A., and Sharma, S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- amino acids, chlorophyll, 14CO2- and 14C-sucrose incorporation, organic acids, primary photosynthetic metabolites, stem, stomatal conductance, sugars, and transpiration rate
- Language:
- Multiple languages
- Description:
- Changes in growth parameters and 14CO2 and [U-14C]-sucrose incorporation into the primary metabolic pools and essential oil were investigated in leaves and stems of M. spicata treated with etherel and gibberellic acid (GA). Compared to the control, GA and etherel treatments induced significant phenotypic changes and a decrease in chlorophyll content, CO2 exchange rate, and stomatal conductance. Treatment with etherel led to increased total incorporation of 14CO2 into the leaves wheras total incorporation from 14C sucrose was decreased. When 14CO2 was fed, the incorporation into the ethanol soluble fraction, sugars, organic acids, and essential oil was significantly higher in etherel treated leaves than in the control. However, [U-14C]-sucrose feeding led to decreased label incorporation in the ethanol-soluble fraction, sugars, organic acids, and essential oils compared to the control. When 14CO2 was fed to GA treated leaves, label incorporation in ethanol-insoluble fraction, sugars, and oils was significantly higher than in the control. In contrast, when [U-14C]-sucrose was fed the incorporation in the ethanol soluble fraction, sugars, organic acids, and oil was significantly lower than in the control. Hence the hormone treatment induces a differential utilization of precursors for oil biosynthesis and accumulation and differences in partitioning of label between leaf and stem. Etherel and GA influence the partitioning of primary photosynthetic metabolites and thus modify plant growth and essential oil accumulation. and Preety Singh ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
105. Influence of foliar-applied triacontanol on growth, gas exchange characteristics, and chlorophyll fluorescence at different growth stages in wheat under saline conditions
- Creator:
- Perveen, S., Shahbaz, M., and Ashraf, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, chlorophyll, salt stress, 2, and 581
- Language:
- Multiple languages
- Description:
- A greenhouse experiment was conducted to examine the effect of foliar application of triacontanol (TRIA) on two cultivars (cv. S-24 and MH-97) of wheat (Triticum aestivum L.) at different growth stages. Plants were grown in full strength Hoagland’s nutrient solution under salt stress (150 mM NaCl) or control (0 mM NaCl) conditions. Three TRIA concentrations (0, 10, and 20 μM) were sprayed over leaves at three different growth stages, i.e. vegetative (V), boot (B), and vegetative + boot (VB) stages (two sprays on same plants, i.e., the first at 30-d-old plants and the second 78-d-old plants). Salt stress decreased significantly growth, net photosynthetic rate (PN), transpiration rate (E), chlorophyll contents (Chl a and b), and electron transport rate (ETR), while membrane permeability increased in both wheat cultivars. Stomatal conductance (gs) decreased only in salt-sensitive cv. MH-97 under saline conditions. Foliar application of TRIA at different growth stages enhanced significantly the growth, PN, gs, Chl a and b contents, and ETR, while membrane permeability was reduced in both cultivars under salt stress. Of various growth stages, foliar-applied TRIA was comparatively more effective when it was applied at V and VB stages. Overall, 10 μM TRIA concentration was the most efficient in reducing negative effects of salinity stress in both wheat cultivars. The cv. S-24 showed the better growth and ETR, while cv. MH-97 exhibited higher nonphotochemical quenching. and S. Perveen, M. Shahbaz, M. Ashraf.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
106. Influence of gibberellic acid on 14CO2 metabolism, growth, and production of alkaloids in Catharanthus roseus
- Creator:
- Srivastava, N. K. and Srivastava, A. K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- amino acids, chlorophyll, 14CO2 photoassimilate partitioning, leaf, organic acids, root, stem, and sugars
- Language:
- Multiple languages
- Description:
- Changes in growth parameters, carbon assimilation efficiency, and utilization of 14CO2 assimilate into alkaloids in plant parts were investigated at whole plant level by treatment of Catharanthus roseus with gibberellic acid (GA). Application of GA (1 000 g m-3) resulted in changes in leaf morphology, increase in stem elongation, leaf and internode length, plant height, and decrease in biomass content. Phenotypic changes were accompanied by decrease in contents of chlorophylls and in photosynthetic capacity. GA application resulted in higher % of total alkaloids accumulated in leaf, stem, and root. GA treatment produced negative phenotypic response in total biomass production but positive response in content of total alkaloids in leaf, stem, and roots. 14C assimilate partitioning revealed that 14C distribution in leaf, stem, and root of treated plants was higher than in untreated and variations were observed in contents of metabolites as sugars, amino acids, and organic acids. Capacity to utilize current fixed 14C derived assimilates for alkaloid production was high in leaves but low in roots of treated plants despite higher content of 14C metabolites such as sugars, amino acids, and organic acids. In spite of higher availability of metabolites, their utilization into alkaloid production is low in GA-treated roots. and N. K. Srivastava, A. K. Srivastava.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
107. Influence of irradiation on cyanide-resistant respiration and AOX1 multi-gene family expression during greening of etiolated rice seedlings
- Creator:
- Feng, H. Q., Li, H. Y., Zhou, G. M., Liang, H. G., Duan, J. G., Zhi, D. J., Li, X., and Ma, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, chloroplast, CO2 fixation, inhibitors, Oryza, oxygen uptake, and salicylhydroxamic acid
- Language:
- Multiple languages
- Description:
- We investigated the differential expression of AOX1 multi-gene family and the regulation of alternative respiratory pathway during initial greening development in leaves of rice (Oryza sativa L.) seedlings. After exposing the dark-grown rice seedlings to continuous irradiation, total respiration (Vt), capacity of alternative pathway (Valt), and their ratio (Valt/Vt) increased with the greening of leaves. In this process, AOX1c transcript increased under constant irradiation, while AOX1a and AOX1b transcripts were hardly detected. Thus AOX1c in rice presents a similar expression pattern as AOX2 does in many dicotyledonous species during greening development. Compared with the rapid increase of cyanideresistant respiration in the presence of photon energy, CO2 fixation was not observed until 8 h after the onset of irradiation. The AOX inhibitor salicylhydroxamic acid (SHAM; 1 mM) inhibited 67.3 % of cyanide-insensitive oxygen uptake in dark-grown leaves and 69.4 % of it in leaves grown under irradiation. Dark-grown plants pre-treated with SHAM were then irradiated for 12 h. SHAM did not obviously modify photosynthetic CO2 fixation rate on a chlorophyll (Chl) content basis in both leaves and simultaneously isolated chloroplasts. Hence during initial greening steps of the plants, the induction of alternative pathway and AOX1 expression by irradiation is not directly linked with carbon assimilation of photosynthesis. The application of SHAM partially limited Chl production in rapidly greening leaves, indicating that Chl synthesis in the process of greening might be medicated to some extent by alternative respiratory pathway. and H. Q. Feng ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
108. Influence of shading inclined tubular photobioreactor surfaces on biomass productivity of C. sorokiniana
- Creator:
- Ugwu, C. U. and Aoyagi, H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- algae, carotenoids, chlorophyll, flashing radiation, and intermittent radiation
- Language:
- Multiple languages
- Description:
- Shading of the tubular photobioreactor (PBR) surfaces that diminished solar irradiance to 70 % led to higher biomass productivity and greater accumulation of total chlorophyll and carotenoids compared to the values obtained when the PBR was completely exposed to full sunlight. and C. U. Ugwu, H. Aoyagi.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
109. Inhibition of root respiration induces leaf senescence in Alhagi sparsifolia
- Creator:
- Tang, G.-L., Li, X.-Y., Lin, L.-S., Hu, Y., and Zeng, F.-J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- obecná botanika, sacharidy, chlorofyl, general botany, carbohydrates, chlorophyll, girdling, phloem transport, photosynthetic pigment, 2, and 581
- Language:
- Multiple languages
- Description:
- Leaf senescence can be induced by numerous factors. In order to explore the relationship between root respiration and leaf senescence, we utilized different types of phloem girdling to control the root respiration of Alhagi sparsifolia and its physiological response. Our results showed that both girdling and inhibition of root respiration led to a decline of stomatal conductance, photosynthesis, transpiration rate, chlorophyll (Chl) a, Chl b, carotenoid (Car) content, Chl a/b, Chl/Car, water potential, and Chl a fluorescence, as well as to an increase of abscisic acid (ABA), proline, and malondialdehyde content in leaves and to upregulation of senescence-associated gene expression. Our present work implied that both inhibition of root respiration and girdling can induce leaf senescence. In comparison with phloem girdling, the leaf senescence caused by inhibition of root respiration was less significant. The reason for girdling-induced senescence was ABA and carbohydrate accumulation. Senescence induced by inhibition of root respiration occurred due to leaf water stress resulting from inhibition of water absorption., G.-L. Tang, X.-Y. Li, L.-S. Lin, Y. Hu, F.-J. Zeng., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
110. Interactive effects of salinity and ozone pollution on photosynthesis, stomatal conductance, growth, and assimilate partioning of wheat (Triticum aestivum L.)
- Creator:
- Hassan, I. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, ear, NaCl, O3, relative growth rate, shoot/root ratio, and 1 000 grain mass
- Language:
- Multiple languages
- Description:
- Plants of an Egyptian cultivar of wheat (Triticum aestivum L. cv. Giza 63) were exposed in open-top chambers (OTCs) for 8 h d-1 for up to 75 d to a factorial combination of two levels of salinity (0 and 50 mM NaCl) and two levels of O3 (filtered air and 50 mm3 m-3). Exposure to 50 mm3 m-3 O3 significantly decreased stomatal conductance (gs), net photosynthetic rate (PN), and chlorophyll (Chl) content by 20, 25, and 21 %, respectively. This reduction resulted in a change in assimilate allocation in favour of shoot growth leading to a decrease in root to shoot ratio and eventually to a decrease in relative growth rate (RGR) of both root and shoot. There was a very large reduction in yield parameters, especially in the number of ears/plant and 1 000-grain mass. Soil salinity significantly reduced PN and gs by 17 and 15 %, respectively, while Chl content was increased by 17 %. Root growth was decreased leading to an increase in root/shoot ratio. Yield parameters were decreased due to salt stress. There was antagonistic interaction between salinity (50 mM NaCl) and O3 (50 mm3 m-3) showing that salinity effectively protects against the adverse effects of O3 by increasing gs during O3 fumigation.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public