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2. Effect of iron deficiency induced changes on photosynthetic pigments, ribulose-1,5-bisphosphate carboxylase, and photosystem activities in field grown grapevine (Vitis Vinifera L. cv. Pinot noir) leaves
- Creator:
- Bertamini, M., Nedunchezhian, N., and Borghi, B.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carotenoids, chlorophyll, fluorescence, electron transport, photosystems 1 and 2, proteins, and ribulose-1,5-bisphosphate carboxylase
- Language:
- Multiple languages
- Description:
- The effect of iron deficiency on photosynthetic pigments, ribulose-1,5-bisphosphate carboxylase (RuBPC), and photosystem activities were investigated in field grown grapevine (Vitis vinifera L. cv. Pinot noir) leaves. The contents of chlorophyll (Chl) (a+b) and carotenoids per unit fresh mass showed a progressive decrease upon increase in iron deficiency. Similar results were also observed in content of total soluble proteins and RuBPC activity. The marked loss of large (55 kDa) and small (15 kDa) subunits of RuBPC was also observed in severely chlorotic leaves. However, when various photosynthetic electron transport activities were analysed in isolated thylakoids, a major decrease in the rate of whole chain (H2O → methyl viologen) electron transport was observed in iron deficient leaves. Such reduction was mainly due to the loss of photosystem 2 (PS2) activity. The same results were obtained when Fv/Fm was evaluated by Chl fluorescence measurements in leaves. Smaller inhibition of photosystem 1 (PS1) activity was also observed in both mild and severely chlorotic leaves. The artificial electron donors, diphenyl carbazide and NH2OH, markedly restored the loss of PS2 activity in severely chlorotic leaves. The marked loss of PS2 activity was evidently due to the loss of 33, 23, 28-25, and 17 kDa polypeptides in iron deficient leaves. and M. Bertamini, N. Nedunchezhian, B. Borghi.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Effect of water deficit on photosynthetic and other physiological responses in grapevine (Vitis vinifera L. cv. Riesling) plants
- Creator:
- Bertamini, M., Zulini, L., Muthuchelian, K., and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- amino acids, chlorophyll, net photosynthetic rate, nitrate reductase, proline, protease, relative water content, and ribulose-1,5-biphosphate carboxylase
- Language:
- Multiple languages
- Description:
- The grapevine (Vitis vinifera L. cv. Riesling) plants subjected to water deficit were studied for changes in relative water content (RWC), leaf dry mass, contents of chlorophyll (Chl), total leaf proteins, free amino acids, and proline, and activities of ribulose-1,5-bisphosphate carboxylase (RuBPC), nitrate reductase (NR), and protease. In water-stressed plants RWC, leaf dry matter, Chl content, net photosynthetic rate (PN), and RuBPC and NR activities were significantly decreased. The total leaf protein content also declined with increase in the accumulation of free amino acids. Concurrently, the protease activity in the tissues was also increased. A significant two-fold increase in proline content was recorded. and M. Bertaminni ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Effects of phytoplasma [stolbur-subgroup (Bois noir-BN)] on photosynthetic pigments, saccharides, ribulose 1,5-bisphosphate carboxylase, nitrate and nitrite reductases, and photosynthetic activities in field-grown grapevine (Vitis vinifera L. cv. Chardonnay) leaves
- Creator:
- Bertamini, M. and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carotenoids, chlorophyll, electron transport, donor side, and photosystem 1 and 2 activities
- Language:
- Multiple languages
- Description:
- In leaves of field-grown grapevine, the contents of chlorophyll, carotenoids, and soluble proteins and the activities of ribulose-1,5-bisphosphate carboxylase (RuBPC) and nitrate (NR) and nitrite (NiR) reductases were decreased in phytoplasma-infected leaves, but the contents of soluble sugars and total saccharides were markedly increased. In isolated thylakoids, phytoplasma caused marked inhibition of whole chain and photosystem 2 (PS2) activities. The artificial exogenous electron donor, diphenyl carbazide, significantly restored the loss of PS2 activity in infected leaves. and M. Bertamini, N. Nedunchezhian.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. 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
6. High irradiance induced changes of photosystem 2 in young and mature needles of cypress (Cupressus sempervirens L.)
- Creator:
- La Porta, N., Bertamini, M., Nedunchezhian, N., and Muthuchelian, K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acclimation to irradiance, chlorophyll fluorescence, D1 protein, donor side, electron transport, photoinhibition, photosystem 2, and proteins
- Language:
- Multiple languages
- Description:
- Photoinhibition of photosynthesis was studied in young and mature detached sun needles of cypress under high irradiance (HI) of about 1 900 μmol m-2 s-1. The degree of photoinhibition was determined by means of the ratio of variable to maximum chlorophyll (Chl) fluorescence (Fv/Fm) and electron transport measurements. Compared with the mature needles, the young needles, containing about half the amount of Chl a+b per unit area, exhibited a higher proportion of total carotenoids (Car) as xanthophyll cycle pigments and had an increased ratio of Car/Chl a+b. The potential efficiency of photosystem (PS) 2, Fv/Fm, markedly declined in HI-treated young needles without significant increase of F0 level. In contrast, the Fv/Fm ratio declined with significant increase of F0 level in mature needles. In isolated thylakoids, the rate of whole chain and PS2 activity markedly decreased in young HI-needles in comparison with mature needles. A smaller inhibition of PS1 activity was observed in both needles. In the subsequent dark incubation, fast recovery was found in both needle Types that reached maximum PS2 efficiencies similar to those observed in non-photoinhibited needles. The artificial exogenous electron donors DPC, NH2OH, and Mn2+ failed to restore the HI-induced loss of PS2 activity in mature needles, while DPC and NH2OH significantly restored it in young needles. Hence, HI-inactivation was on the donor side of PS2 in young needles and on the acceptor side of PS2 in mature needles. Quantification of the PS2 reaction centre proteins D1 and 33 kDa protein of water splitting complex following HI-exposure of needles showed pronounced differences between young and mature needles. The large loss of PS2 activity in HI-needles was due to the marked loss of D1 protein of the PS2 reaction centre in mature needles and of the 33 kDa protein in young needles. and N. La Porta ... [et al.]
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Photoinhibition and recovery of photosystem 2 in grapevine (Vitis vinifera L.) leaves grown under field conditions
- Creator:
- Bertamini, M. and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, diurnal course, donor side, electron transport, photosystems 1 and 2, and proteins
- Language:
- Multiple languages
- Description:
- Photoinhibition of photosynthesis was investigated in grapevine (Vitis vinifera L.) exposed to 2 or 4h of high irradiance (HI) (1 700-1 800 μmol m-2 s-1) leaves under field conditions at different sampling time in a day. The degree of photoinhibition was determined by means of the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) and photosynthetic electron transport measurements. When the photochemical efficiency of photosystem 2 (PS2), Fv/Fm, markedly declined, F0 increased in both 2 (HI2) and 4 h (HI4) HI leaves sampled at midday. When various photosynthetic activities were followed on isolated thylakoids, HI4 leaves showed significantly higher inhibition of whole chain and PS2 activity than the HI2 leaves sampled at midday. Later, the leaves reached maximum PS2 efficiencies similar to those observed early in the morning during sampling at evening. The artificial exogenous electron donor Mn2+ failed to restore PS2 activity in both variants of leaves, while DPC and NH2OH significantly restored PS2 activity in HI4 midday leaf samples. Quantification of the PS2 reaction centre protein D1 and 33 kDa protein of water splitting complex following midday exposure of leaves showed pronounced differences between HI2 and HI4 leaves. The marked loss of PS2 activity noticed in midday samples was mainly due to the marked loss of D1 protein in HI2, while in HI4 it was mainly 33-kDa protein. and M. Bertamini, N. Nedunchezhian.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Photoinhibition of photosynthesis in leaves of grapevine (Vitis vinifera L. cv. Riesling). Effect of chilling nights
- Creator:
- Bertamini, M., Muthuchelian, K., Rubinigg, M., Zorer, R., and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acceptor side, chlorophyll fluorescence, D1 protein, diurnal course of photosynthetic activities, electron transport, Mn, NH2OH, photosystems 1 and 2, and photoinhibition
- Language:
- Multiple languages
- Description:
- Photoinhibition of photosynthesis was investigated in control (C) and chilling night (CN) leaves of grapevine under natural photoperiod at different sampling time in a day. The degree of photoinhibition was determined by means of the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) and photosynthetic electron transport measurements. When the potential efficiency of photosystem (PS) 2, Fv/Fm was measured at midday, it markedly declined with significant increase of F0 in CN leaves. In isolated thylakoids, the rate of whole chain and PS2 activity were markedly decreased in CN leaves than control leaves at midday. A smaller inhibition of PS1 activity was also observed in both leaf types. Later, the leaves reached maximum PS2 efficiencies similar to those observed in the morning during sampling at evening. The artificial exogenous electron donors diphenyl carbazide, NH2OH, and Mn2+ failed to restore the PS2 activity in both leaf types at midday. Thus CN enhanced inactivation on the acceptor side of PS2 in grapevine leaves. Quantification of the PS2 reaction centre protein D1 following midday exposure of leaves showed pronounced differences between C and CN leaves. The marked loss of PS2 activity in CN leaves noticed in midday samples was mainly due to the marked loss of D1 protein of the PS2 reaction centre. and M. Bertamini ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Photoinhibition of photosynthesis in sun and shade grown leaves of grapevine (Vitis vinifera L.)
- Creator:
- Bertamini, M., Muthuchelian, K. , and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, donor side, D1 protein, electron transport, photoinhibition, and photosystems 1 and 2
- Language:
- Multiple languages
- Description:
- The degree of photoinhibition of sun and shade grown leaves of grapevine was determined by means of the ratio of variable to maximum chlorophyll (Chl) fluorescence (Fv/Fm) and electron transport measurements. The potential efficiency of photosystem 2 (PS2), Fv/Fm, markedly declined under high irradiance (HI) in shade leaves with less than 10 % of F0 level. In contrast, Fv/Fm ratio declined with about 20 % increase of F0 level in sun leaves. In isolated thylakoids, the rate of whole chain and PS2 activity in HI shade and sun leaves was decreased by about 60 and 40 %, respectively. A smaller inhibition of photosystem 1 (PS1) activity was also observed in both leaf types. In the subsequent dark incubation, fast recovery was observed in both leaf types that reached maximum PS2 efficiencies similar to non-photoinhibited control leaves. The artificial exogenous electron donors DPC, NH2OH, and Mn2+ failed to restore the HI-induced loss of PS2 activity in sun leaves, while DPC and NH2OH were significantly restored in shade leaves. Hence HI in shade leaves inactivates on the donor side of PS2 whereas it does at the acceptor side in sun leaves, respectively. Quantification of the PS2 reaction centre protein D1 and the 33 kDa protein of water splitting complex following HI-treatment of leaves showed pronounced differences between shade and sun leaves. The marked loss of PS2 activity in HI leaves was due to the marked loss of D1 protein of the PS2 reaction centre protein and the 33 kDa protein of the water splitting complex in sun and shade leaves, respectively. and M. Bertamini, K. Muthuchelian, N. Nedunchezhian.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Photoinhibition of photosynthesis in Vitis berlandieri and Vitis rupestris leaves under field conditions
- Creator:
- Bertamini, M. and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, donor side, electron transport, and photosystem 2
- Language:
- Multiple languages
- Description:
- Photoinhibition of photosynthesis was investigated in Vitis berlandieri and Vitis rupestris leaves under field conditions at different sampling time in a day. The degree of photoinhibition was determined by means of the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) and photosynthetic electron transport measurements. When the photochemical efficiency of PS2, Fv/Fm, markedly declined, F0 increased significantly in leaves of V. berlandieri, while F0 did not increase in V. rupestris leaves. Isolated thylakoids of leaves of V. berlandieri showed significant inhibition of whole chain and PS2 activities at midday. A smaller inhibition was observed for V. rupestris. Later, the leaves reached maximum PS2 efficiencies similar to those observed early in the morning during sampling at evening. The artificial exogenous electron donor Mn2+ failed to restore PS2 activity in both species, while DPC and NH2OH significantly restored PS2 activity in V. rupestris midday leaf samples. Quantification of the PS2 reaction centre protein D1 and 33 kDa protein of water splitting complex following midday exposure of leaves showed pronounced differences between V. berlandieri and V. rupestris leaves. The marked loss of PS2 activity noticed in midday samples was mainly due to the marked loss of D1 protein in V. berlandieri while in V. rupestris it was the 33 kDa protein. and M. Bertamini, N. Nedunchezhian.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public