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2. Changes in morphology, anatomy, and photosynthetic capacity of needles of Japanese larch (Larix kaempferi) seedlings grown in high CO2 concentrations
- Creator:
- Eguchi, N., Fukatsu, E., Funada, R., Tobita, H., Kitao, M., Maruyama, Y., and Koike, T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carboxylation efficiency, cell number, intercellular CO2 concentration, mesophyll surface area, needle thickness and width, net photosynthetic rate, nitrogen content, specific leaf area, and starch
- Language:
- Multiple languages
- Description:
- Photosynthetic traits of two-year-old Japanese larch seedlings (Larix kaempferi Carr.) grown at elevated CO2 concentrations were studied in relation to structural changes in the needles. Seedlings were grown at two CO2 concentrations, 360 (AC) and 720 (EC) μmol mol-1 at high and low nutrient supply rates, high N (HN) and low N (LN). The photosynthetic capacity fell significantly in EC+LN, but increased significantly in EC+HN. Since the mesophyll surface area exposed to intercellular space per unit leaf area (Ames/A) is correlated with the photosynthetic rate, we measured Ames/A for larch needles growing in EC. Changes of Ames/A in both EC+HN and EC+LN were very similar to the changes in photosynthetic capacity. This suggests that the changes of Ames/A in EC probably caused the changes in the photosynthetic capacity. The changes of Ames/A in EC were attributed to changes in the mesophyll cell size and mesophyll cell number. The photosynthetic capacity in EC can be explained by taking morphological and structural adaptations into account as well as biochemical factors. and N. Eguchi ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Ecophysiological responses of Cunninghamia lanceolata to nongrowing-season warming, nitrogen deposition, and their combination
- Creator:
- Yu, L., Dong, T. F., Lu, Y. B., Song, M. Y., and Duan, B. L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fruktóza, škrob, chlorofyl, fructose, starch, chlorophyll, fluorescence chlorofylu, výměna plynu, malondialdehyde, reaktivní formy kyslíku, chlorophyll fluorescence, gas exchange, reactive oxygen species, maximal quantum yield of PSII photochemistry, 2, and 581
- Language:
- Multiple languages
- Description:
- Warming winter and atmospheric nitrogen (N) deposition are expected to have effects on net primary production (NPP) of Chinese fir (Cunninghamia lanceolata) plantation and implications for plantation carbon sequestration. The effects of nongrowing-season warming on plant morphological and physiological traits were investigated in a greenhouse experiment with two-year-old C. lanceolata seedlings. Elevated temperature (ET) during the nongrowing season significantly increased the net photosynthetic characteristics. The strongest effects occurred during warming period from 1 December 2014 to 1 February 2015 (W1). Moreover, the carbohydrate concentration was elevated due to the warming during W1, but it declined during four months of the warming (from 1 December 2014 to 1 April 2015, W2). The seedlings kept under N deposition (CN) showed a positive effect in all the above-mentioned parameters except δ13C. Significant interactions between ET and N deposition were observed in most parameters tested. At the end of the experiment (W2), the seedlings exposed to a combined ET and N deposition treatment exhibited the highest carbon contents. Our results showed that N deposition might ameliorate the negative effects of the winter warming on the carbon content., L. Yu, T. F. Dong, Y. B. Lu, M. Y. Song, B. L. Duan., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Effect of reddening of cotton (Gossypium hirsutum L.) leaves on the ultrastructure of mesophyll cells
- Creator:
- Stoyanova-Koleva, D., Edreva, A., Velikova, V., and Gürel, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chloroplast, osmophillic aggregation, peristromium, peroxisome, starch, and transmission electron microscopy
- Language:
- Multiple languages
- Description:
- The ultrastructure of cotton leaves, exhibiting reddening as symptom of physiological disorder, was examined by means of transmission electron microscopy. Osmiophilisation of the membrane compartment was established. Massive agglomerations on the tonoplast in the vacuole of cells under the adaxial epidermis were observed, and were referred to as electron-dense osmiophilic substance, most probably of anthocyanin nature. In chloroplast stroma a zone of low electron density enclosing numerous osmiophilic aggregations of unclear chemical character was differentiated. Fragmentation and severe destruction of thylakoids in chloroplasts of reddening cotton leaves was not detected. and D. Stoyanova-Koleva ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Effect of salinity on photosynthesis and biochemical characteristics in mulberry genotypes
- Creator:
- Agastian, P., Kingsley, S. J., and Vivekanandan, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carotenoids, chlorophyll, glycine betaine, Morus alba, phenols, proline, proteins, saccharides, and starch
- Language:
- Multiple languages
- Description:
- Mulberry genotypes were subjected to salinity (0-12 mS cm-1) in pot culture experiment. Chlorophyll and total carotenoid contents were reduced considerably by salinity. At low salinity, photosynthetic CO2 uptake increased over the control, but it decreased at higher salinity. Contents of soluble proteins, free amino acids, soluble sugars, sucrose, starch, and phenols increased at salinity of 1-2 mS cm-1 and decreased at higher salinity (8-12 mS cm-1). Glycine betaine accumulated more than proline, the maximum accumulation of both was at salinity of 2-4 mS cm-1. Among the genotypes studied, BC2-59 followed by S-30 showed better salinity tolerance than M-5. and P. Agastian, S. J. Kingsley, M. Vivekanandan.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Effect of Zn2+ stress in rice (Oryza sativa cv. Manhar) on growth and photosynthetic processes
- Creator:
- Ajay and Rathore, V.S.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- carotenoids, thylakoids, sugars, starch, relative growth rate, photosynthates, Hill reaction, cyclic and non-cyclic photophosphorylation, and chlorophyll
- Language:
- Multiple languages
- Description:
- Effect of three Zn2+ concentrations, i.e. 0.075 (cl), 7.50 (c2) and 37.5 (c3) jiM, on rice seedlings was studied at three stages, i.e. 1, 14 and 21 d after transplantation. Typical deficiency symptoms were observed in both solution and sand cultures of cl and c2, but the effects were more pronounced in the solution culture. The c3 concentration was toxic. There was marked reduction in growth, chlorophyll (Chl) contents (particularly Chl b), Hill reaction activity, photophosphorylation rate (particularly non-cyclic photophosphorylation), thylakoid phosphorylation, and i'‘C02-fixation at the cl concentration. However, a similar reduction was also observed in thylakoid phosphorylation at the c3 concentration. Hence the optimum zinc concentration in the nutrient medium lied between c2 and c3 Zn2+. By regression the theoretical optimum Zn concentration was calculated as 19.20 pM (1.28 mg kg'i) Zn2+. Partitioning of ^'^C-photosynthates indicated reduced allocation to sugar and starch fractions and increased fřee amino acids concentration at the cl concentration and vice-versa at c2 and c3.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Effects of cadmium and gibberellin on growth and photosynthesis of Glycine max
- Creator:
- Ghorbanli, M., Kaveh, S. Hadad, and Sepehr, M. Farzami
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, CO2 compensation concentration, dry matter production, growth rate, leaf area, net assimilation rate, root, shoot, and starch
- Language:
- Multiple languages
- Description:
- The effects of 0, 2.5, 5.0, and 10.0 mg(Cd2+) m-3 [Cd(NO3)2×4 H2O] and 0 and 10.0 mg m-3 gibberellin on certain parameters of photosynthesis and growth in soybean (Glycine max L. cv. Pershing) plants were studied. With increasing Cd2+ concentration in the Hoagland nutrient solution, the contents of chlorophyll and CO2 compensation concentration decreased. The addition of 10 mg m-3 gibberellin reduced the negative effects of Cd2+ in shoot and root growth. With increasing of Cd2+ concentration in the culture medium, the dry matter production in both the roots and shoots decreased as shown by the decline in growth rate (PGR), net assimilation rate (NAR), and leaf area ratio. The addition of gibberellin caused a partial elimination of the Cd effects on the roots and shoots and the PGR and NAR and it increased leaf area and length of stem. and M. Ghorbanli, S. Hadad Kaveh, M. Farzami Sepehr.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Effects of NaCl on photosynthetic pigments, saccharides, and chloroplast ultrastructure in leaves of tomato cultivars
- Creator:
- Khavari-Nejad, R. A. and Mostofi, Y.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- β-carotene, chlorophyll, grana, Lycopersicon esculentum, saccharides, soluble sugars, starch, and thylakoids
- Language:
- Multiple languages
- Description:
- In leaves of four tomato (Lycopersicon esculentum Mill.) cultivars (Red Cloud, Floradade, Peto 95, and Scorpio) the contents of chlorophyll (Chl) (a+b), Chl a, and β-carotene decreased due to 100 mM NaCl treatment as compared with those of controls. The contents of soluble sugars and total saccharides were significantly increased in leaves of NaCl-treated plants, but the starch content was not significantly affected. Transmission electron microscopy indicated that in leaves of NaCl-treated plants, the chloroplasts were aggregated, the cell membranes were distorted and wrinkled, and there was no sign of grana and thylakoid structures in chloroplasts. and R. A. Khavari-Nejad, Y. Mostofi.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Effects of phytoplasma infection on growth and photosynthesis in leaves of field grown apple (Malus pumila Mill. cv. Golden Delicious)
- Creator:
- Bertamini, M., Muthuchelian, K., Grando, M. S., and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- amino acids, chlorophyll content and fluorescence, electron donor, nitrate reductase, photosystem, phytoplasma, proteins, ribulose-1,5-biphosphate carboxylase, sugars, and starch
- Language:
- Multiple languages
- Description:
- The contents of chlorophyll (Chl), leaf biomass, and soluble proteins were markedly decreased in phytoplasma infected apple leaves. Similar results were also observed for ribulose-1,5-bisphosphate carboxylase, 14CO2 fixation, and nitrate reductase activity. In contrast, the contents of sugars, starch, amino acids, and total saccharides were significantly increased in phytoplasma infected leaves. In isolated chloroplasts, phytoplasma infection caused marked inhibition of whole photosynthetic electron chain and photosystem 2 (PS2) activity. The artificial exogenous electron donor, diphenyl carbazide, significantly restored the loss of PS2 activity in infected leaves. Similar results were obtained when Fv/Fm was evaluated by in vivo Chl a fluorescence kinetic measurements. and M. Bertamini ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Effects of shoot girdling on photosynthetic capacity, leaf carbohydrate, and bud abscission in pistachio (Pistacia vera L.)
- Creator:
- Vemmos, S. N., Papagiannopoulou, A., and Coward, S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- biologie, biology, areal leaf mass, biennial bearing, chlorophyll, net photosynthetic rate, nitrogen, starch, stomatal conductance, sugars, 2, and 57/59
- Language:
- Multiple languages
- Description:
- The effects of shoot girdling on stomatal conductance (gs), leaf photosynthesis (PN), concentrations of carbohydrates, nitrogen and chlorophyll (Chl) in leaves, areal leaf mass (ALM), the diameter and length of shoots, and bud abscission in pistachio were investigated. Girdling individual shoots at the base of the current year’s shoot (girdle I), separating inflorescent buds on the terminal current year’s shoot from the developing fruits on the previous year’s shoot, reduced inflorescent bud abscission by 70% in comparison to nongirdled controls. Girdle I significantly reduced concentrations of nitrogen in leaves but increased those of nonstructural carbohydrates particularly of starch. Shoot diameter increased by 13.1% and 26.4% at 33 and 81 days after girdling (DAG), respectively, compared to 1% and 3.4% in the control, respectively. Both the leaf dry mass/fresh mass ratio and ALM were increased significantly by girdle I from 12 DAG. The concentrations of Chl a, Chl b, Chl (a+b), as well as the ratio of Chl a/b, all decreased with girdle I. The greatest negative effect of girdle I was on gs and PN. PN was reduced by 55% of its initial value and was 44% less than in the control leaves at 10 DAG, and fell to approximately 30% that of the control from 21 DAG. In contrast, girdling at the base of one-year-old shoots (girdle II), thus not separating fruits from the inflorescent buds, did not significantly affect gs or PN. The effect of girdling on PN and the possible factors that are involved in the reduction of photosynthesis in pistachio are discussed., S. N. Vemmos, A. Papagiannopoulou, S. Coward., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
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