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Start Over Creator Khan, N. A.

1. Activities of carbonic anhydrase and ribulose-1,5-bisphosphate carboxylase, and dry mass accumulation in Brassica juncea following defoliation

Creator:
Khan, N. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
ddry mass accumulation, leaf dry mass, and mustard
Language:
Multiple languages
Description:
The effect of 30 % defoliation of shaded leaves in lower layers of plant was studied on activities of carbonic anhydrase (CA) and ribulose-1,5-bisphosphate carboxylase (RuBPC), leaf dry mass per unit leaf area, and plant dry mass of mustard (Brassica juncea). Removal of 30 % of leaves resulted in increased CA and RuBPC activities of leaves, and leaf and plant dry masses.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Activity of 1-aminocyclopropane carboxylic acid synthase in two mustard (Brassica juncea L.) cultivars differing in photosynthetic capacity

Creator:
Khan, N. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
ACC oxidase, carbonic anhydrase, dry mass, intercellular CO2 concentration, leaf area, net photosynthetic rate, plant hormones, and stomatal conductance
Language:
Multiple languages
Description:
The pattern of activity of 1-aminocyclopropane carboxylic acid synthase (ACS) was similar to photosynthetic and growth traits observed at 30, 45, and 60 d after sowing in mustard (Brassica juncea L.) cultivars Varuna and RH 30 differing in photosynthetic capacity. Higher activity of ACS and therefore ethylene release in Varuna than RH 30 increased stomatal conductance, intercellular CO2 concentration, carboxylation rate (carbonic anhydrase and intrinsic water use efficiency), and thus net photosynthetic rate (PN) and leaf and plant dry masses (DM) at all sampling times. Moreover, Varuna also had larger leaf area which contributed to higher PN and DM. A positive correlation between ACS activity and PN and leaf area was found in both the cultivars. Thus ACS activity may affect PN through ethylene-induced changes on foliar gas exchange and leaf growth.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Analyzing the significance of defoliation in growth, photosynthetic compensation and source-sink relations

Creator:
Iqbal, N., Masood, A., and Khan, N. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, carbon, defoliation, nitrogen, photosynthetic potential, sink, source, 2, and 58
Language:
Multiple languages
Description:
Leaf canopy plays a determining role influencing source-sink relations as any change in source activity (photosynthesis) affects sink metabolism. Defoliation (removal of leaves) influences growth and photosynthetic capacity of plants, remobilizes carbon and nitrogen reserves and accelerates sink metabolism, leading to improved source-sink relations. The response of plants to defoliation could be used to manipulate source-sink relations by removing lower and senescing leaves to obtain greatest photosynthetic capacity and efficient carbon and nitrogen metabolism under optimal and stressful environments. The present work enhances our current understanding on the physiological responses of plants to defoliation and elaborates how defoliation influences growth, photosynthetic capacity and source-sink relations under optimal and changing environmental conditions., N. Iqbal, A. Masood, and N. A. Khan., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. ATP-sulfurylase activity, photosynthesis, and shoot dry mass of mustard (Brassica juncea L.) cultivars differing in sulfur accumulation capacity

Creator:
Nazar, R., Khan, N. A., and Anjum, N. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
dry mass, leaf area, nitrogen content, and sulfate transport index
Language:
Multiple languages
Description:
Sulfur (S) is an essential nutrient element required in a large quantity by mustard. S regulates photosynthesis and plant growth through improving nitrogen (N) acquisition. Mustard cultivars Alankar, Varuna, Pusa Jai Kisan, and SS2 differing in S accumulation capacity calculated as sulfate transport index (STI) were tested for ATP-sulfurylase activity, S and N accumulation, photosynthesis, and shoot dry mass (DM) at 30 and 60 d after sowing (DAS). The activity of ATP-sulfurylase, shoot N content, net photosynthetic rate (PN), leaf area, and shoot DM of the cultivars were in the order: Pusa Jai Kisan>Alankar>Varuna>SS2. ATP-sulfurylase activity was strongly and positively correlated with PN and shoot DM in all the cultivars. Hence ATP-sulfurylase activity may be used as a physiological trait for augmenting photosynthesis and shoot DM. and R. Nazar, N. A. Khan, N. A. Anjum.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Effects of cadmium stress upon activities of antioxidative enzymes, photosynthetic rate, and production of phytochelatins in leaves and chloroplasts of wheat cultivars differing in yield potential

Creator:
Ahmad, I., Naeem, M., Khan, N. A., and Samiullah
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
ascorbate peroxidase, ATP-sulfurylase, catalase, glutathione, glutathione reductase, stomatal conductase, superoxide dismutase, Triticum, and water use efficiency
Language:
Multiple languages
Description:
We tested the mode of action of Cd on photosynthesis and activities of ATP-sulfurylase (ATP-S), catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), and on contents of phytochelatins (PCs) and glutathione (GSH) in two cultivars of wheat (Triticum aestivum L.) PBW-343 and WH-542 differing in yield potential. Cd treatment increased Cd content and photosynthetic activity in PBW-343 more than in WH-542. The activities of APX, GR, ATP-S, and synthesis of PCs and GSH were also increased by Cd, but the CAT and SOD activities were inhibited in both the cultivars. The efficient functioning of antioxidative enzymes, production of PCs and GSH, helped in counteracting the effects of Cd namely in PBW-343, protected photosynthetic ability, and increased the tolerance to Cd. and I. Ahmad ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Moringa oleifera-rich diet and T cell calcium signaling in spontaneously hypertensive rats

Creator:
Attakpa, E. S., Bertin, G. A., Chabi, N. W., Atègbo, J.-M., Seri, B., and Khan, N. A.
Type:
article, model:article, and TEXT
Subject:
Moringa oleifera, genetic hypertension, intracellular calcium, immunomodulation, T cells, and rats
Language:
English
Description:
Moringa oleifera is a plant whose fruits, roots and leaves have been advocated for traditional medicinal uses. The physicochemical analysis shows that Moringa oleifera contains more dietary polyunsaturated fatty acids (PUFA) than saturated fatty acids (SFA). The consumption of an experimental diet enriched with Moringa oleifera extracts lowered blood pressure in spontaneously hypertensive rats (SHR), but not in normotensive Wistar-Kyoto (WKY) rats as compared to rats fed an unsupplemented control diet. Anti-CD3-stimulated T cell proliferation was diminished in both strains of rats fed the Moringa oleifera. The experimental diet lowered secretion of interleukin-2 in SHR, but not in WKY rats compared with rats fed the control diet. Studies of platelets from patients with primary hypertension and from SHR support the notion that the concentration of intracellular free calcium [Ca2+]i is modified in both clinical and experimental hypertension. We observed that the basal, [Ca2+]i was lower in T cells of SHR than in those of WKY rats fed the control diet. Feeding the diet with Moringa oleifera extracts to WKY rats did not alter basal [Ca2+]i in T cells but increased basal [Ca2+]i in SHR. Our study clearly demonstrated that Moringa oleifera exerts antihypertensive effects by inhibiting the secretion of IL-2 and modulates T cell calcium signaling in hypertensive rats.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

7. Photosynthetic and growth responses of two mustard cultivars differing in phytocystatin activity under cadmium stress

Creator:
Per, T. S., Khan, S., Asgher, M., Bano, B., and Khan, N. A.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
kadmium, bavlna, chlorofyl, cadmium, cotton, chlorophyll, fluorescence chlorofylu, fluorescenční spektra, oblast listu, phytocystatin, suchá rostlinná hmota, kultivary, rychlost přenosu elektronů, kaštan, chlorophyll fluorescence, fluorescence spectra, leaf area, plant dry mass, ascorbate peroxidase, ATP-sulphurylase, cultivars, effective quantum yield of PSII photochemistry, electron transport rate, chestnut, maximal quantum yield of PSII photochemistry, 2, and 581
Language:
Multiple languages
Description:
Cadmium inhibits photosynthetic capacity of plants by disturbing protein conformations, whereas phytocystatins prevent degradation of target proteins and are involved in abiotic stress tolerance. Two mustard (Brassica juncea L.) cultivars, Ro Agro 4001 and Amruta, were grown with Cd (50 µM) in order to study physiological and biochemical basis of differences in Cd tolerance. Amruta accumulated higher Cd and H2O2 concentrations in leaves than that of Ro Agro 4001. Cd significantly decreased photosynthesis and growth of plants in both cultivars by reducing a chlorophyll content, gas exchange parameters, and activity of Rubisco; the effects were more prominent in Amruta than those in Ro Agro 4001. The greater photosynthesis and growth of Ro Agro 4001 under Cd stress might be attributed to its higher phytocystatin activity together with greater ascorbate peroxidase activity, photosynthetic nitrogen-use efficiency, sulphur assimilation (ATP-sulphurylase activity and S content), and contents of cysteine and reduced glutathione compared to Amruta. In contrast, the activity of superoxide dismutase (SOD) was higher in Amruta than that of Ro Agro 4001 under control conditions, whereas the Cd treatment increased significantly the SOD activity in both cultivars with the greater increase in Ro Agro 4001. The fluorescence spectra of phytocystatin showed a lesser change in Ro Agro 4001 under Cd stress than that in Amruta suggesting higher resistance of Ro Agro 4001 to Cd. The higher phytocystatin activity under Cd stress in Ro Agro 4001 compared to Amruta enabled the plants to protect their proteins more efficiently. This resulted in a greater increase of photosynthetic capacity in Ro Agro 4001 than that of Amruta. Thus, the phytocystatin activity may be considered as a physiological parameter for augmenting photosynthesis and growth of mustard under Cd stress., T. S. Per, S. Khan, M. Asgher, B. Bano, N. A. Khan., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public