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Start Over Creator Pandey, D. M.

1. Changes in contents of photosynthetic pigments and ribulose-1,5-bisphosphate carboxylase activity during the development of globular somatic embryo into the plantlet of Siberian ginseng

Creator:
Pandey, D. M., Kim, J.-W., Lee, W.-S., and Yeo, U.-D.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
carotenoids, chlorophyll, and Eleutherococcus senticosus
Language:
Multiple languages
Description:
During the development of the globular embryos via heart-shaped, torpedo-shaped, and cotyledonary embryos into plantlets, contents of chlorophyll (Chl) a and b and carotenoids, and activity of ribulose-1,5-bisphosphate carboxylase (RuBPC, EC 4.1.1.39) were investigated. In the solid cultivation (SC) the contents of Chl a, Chl b, Chl a/b, and total pigments increased up to plantlet stage. In the liquid cultivation (LC), contents of Chl a, Chl b, and total pigments increased till the torpedo-shaped stage, but decreased with the further development up to plantlets stage. During SC, RuBPC activity increased up to the torpedo-shaped embryo stage, but in the LC RuPBC activity increased continuously with the progress in the developmental stages. The correlations between Chl a and RuBPC activity on the SC and LC were negative, r = -0.26 and -0.56, respectively. and D. M. Pandey ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Dynamic changes of photosynthetic pigments in soybean callus under high irradiance

Creator:
Pandey, D. M., Kim, K.-H., and Yeo, U.-D.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
carotenoids, chlorophyll, Glycine max, HPLC, photoinhibition, spectrophotometry, violaxanthin, and zeaxanthin
Language:
Multiple languages
Description:
Dynamic changes of neoxanthin (NEO), violaxanthin (VIO), anteraxanthin (ANT), zeaxanthin (ZEA), chlorophyll (Chl) a, Chl b, α-carotene, β-carotene, and their behaviour under increasing duration of high irradiance (HI) were investigated in the soybean hypocotyl callus culture. The calli were induced on solid (1.1 % agar) MS medium (pH 5.8) supplemented with 4.52 μM 2,4-D, 2.32 μM kinetin, and 3 % sucrose. After 30 d of culture, the green calli were irradiated with "white light" (133W m-2) for 0, 3.5, and 24 h. HPLC profiles were separated on a C18 column. With increasing duration of HI, the content of total carotenoids (Cars) increased, but the ratio of Chl a+b/Cars decreased. With lengthening the duration of HI, there was induction of ZEA. Contents of ANT, α-carotene, and β-carotene remained nearly constant, but ratio of ZEA/Chl a+b increased with lengthening the HI duration. and D. M. Pandey, K. H. Kim, U. D. Yeo.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Effects of different irradiances on the photosynthetic process during ex-vitro acclimation of Anoectochilus plantlets

Creator:
Pandey, D. M., Yu, K. W., Wu, R. Z., Hahn, E.-J., and Paek, K.-Y.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll a fluorescence, electron transfer rate, photoinhibition, photosystem 2, ribulose-1,5-bisphosphate carboxylase, oxygenase, stomatal conductance, transpiration, and xanthophylls
Language:
Multiple languages
Description:
Six months old in vitro-grown Anoectochilus formosanus plantlets were transferred to ex-vitro acclimation under low irradiance, LI [60 µmol(photon) m-2 s-1], intermediate irradiance, II [180 µmol(photon) m-2 s-1], and high irradiance, HI [300 µmol(photon) m-2 s-1] for 30 d. Imposition of II led to a significant increase of chlorophyll (Chl) b content, rates of net photosynthesis (PN) and transpiration (E), stomatal conductance (gs), electron transfer rate (ETR), quantum yield of electron transport from water through photosystem 2 (ΦPS2), and activity of ribulose-1,5-bisphosphate carboxylase/ oxygenase (RuBPCO, EC 4.1.1.39). This indicates that Anoectochilus was better acclimated at II compared to LI treatment. On the other hand, HI acclimation led to a significant reduction of Chl a and b, PN, E, gs, photochemical quenching, dark-adapted quantum efficiency of open PS2 centres (Fv/Fm), probability of an absorbed photon reaching an open PS2 reaction centre (Fv'/Fm'), ETR, ΦPS2, and energy efficiency of CO2 fixation (ΦCO2/ΦPS2). This indicates that HI treatment considerably exceeded the photo-protective capacity and Anoectochilus suffered HI induced damage to the photosynthetic apparatus. Imposition of HI significantly increased the contents of antheraxanthin and zeaxanthin (ZEA), non-photochemical quenching, and conversion of violaxanthin to ZEA. Thus Anoectochilus modifies its system to dissipate excess excitation energy and to protect the photosynthetic machinery. and D. M. Pandey ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. High irradiance effects on the xanthophyll cycle pigments and the activity of violaxanthin de-epoxidase in soybean callus

Creator:
Pandey, D. M., Kim, K. H., Kang, K. H., and Yeo, U. D.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
antheraxanthin, Glycine max, HPLC, neoxanthin, violaxanthin, and zeaxanthin
Language:
Multiple languages
Description:
High irradiance (HI) effects on xanthophyll cycle pigments (XCP) and activity of violaxanthin de-epoxidase (VDE) in terms of de-epoxidation index (DEI) were studied in soybean calli. The calli from the hypocotyl segments of 5-d seedlings were induced on a solid (1.1 % agar) MS medium (pH 5.8) supplemented with 4.52 μM 2,4-dichloro-phenoxyacetic acid, 2.32 μM kinetin, and 3 % sucrose. After a 30 d cultivation, the green calli were irradiated for 24 h with "white light" (HI, 1 300 μmol m-2 s-1) and VDE was isolated from the photosystem 2 (PS2) particles. In the control (0 h irradiation) callus, the reaction of PS2 particles with VDE in the presence or absence of Tween 20 resulted in the decrease of VIO content and the increase of ZEA content. In the 24 h HI-callus, the reaction of PS2 particles in the absence of VDE led to the decrease of VIO and ANT contents and increase of ZEA content. In the control, DEIs in the presence of VDE with or without 0.1 %Tween 20 (1.04 and 1.06, respectively) were significantly higher than the DEI (0.76) in the absence of VDE. In the HI-callus, DEIs in the presence of VDE with or without 0.1 %Tween 20 (0.98 and 0.96, respectively) were similar to that (1.03) in the absence of VDE. and D. M. Pandey ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Hormonal regulation of photosynthetic enzymes in cotton under water stress

Creator:
Pandey, D. M., Goswami, C. L., Kumar, B., and Jain, Sudha
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
abscisic acid, benzylaminopurine, carbonic anhydrase, ethrel, gibberellic acid, Gossypium hirsulum, phosphoenolpyruvate carboxylase, and ribulose-1,5-bisphosphate carboxylase/oxygenase
Language:
Multiple languages
Description:
Activities of ribulose bisphosphate carboxylase/oxygenase (RuBPCO), phosphoenolpyruvate carboxylase (PEPC), and carbonic anhydrase (CA) were determined in leaves of cotton (Gossypium hirsutum L. cv. H-777) subjected to 8-d waterlogging (WL) at the vegetative stage, or to drought (D) at the reproductive stage, or to interaction of both stresses. The soil moisture of control plants was kept at field capacity. One day prior to stress various growth hormones (5 μM) were sprayed up to runoff. WL reduced RuBPCO and CA activities, while PEPC activity increased. Upon D, RuBPCO and PEPC activities were reduced while CA activity was increased. Imposition of both stresses increased activities of all three enzymes. Effect of stresses on enzyme activity was alleviated by benzylaminopurine (BAP), but indol-3-yl-acetic acid was more promoting under interactive stress. No CA activity with BAP was observed during interactive stress. and D. M. Pandey ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public