scholarly journals Abscisic acid as a factor in regulation of photosynthetic carbon metabolism of pea seedlings

2014 ◽  
Vol 51 (2) ◽  
pp. 229-240 ◽  
Author(s):  
Maria Faltynowicz ◽  
Waldemar Lechowicz ◽  
Jerzy Poskuta
Keyword(s):  
Abscisic Acid ◽  
Carbon Metabolism ◽  
Rubp Carboxylase ◽  
Pep Carboxylase ◽  
Pea Seedlings ◽  
Photosynthetic Carbon ◽  
Photosynthetic Carbon Metabolism ◽  
Sugar Phosphates ◽  
Reduced Activity ◽  
Endogenous Aba

The influence of abscisic acid (ABA) on carbon metabolism and the activity of ribulosebisphosphate (RuBP) and phosphoenolpyruvate (PEP) carboxylases in 8-day-old pea seedlings was investigated. It was endeavoured to correlate the changes observed in metabolic processes with the endogenous ABA level. In plants treated with ABA incorporation of labeled carbon into sucrose, glucose, fructose and sugar phosphates was depressed, while <sup>14</sup>C incorporation into starch, ribulose and malic acid was enhanced. The activity of RuBP carboxylase was considerably lowered, whereas that of PEP carboxylase was slightly increased. It is considered that inhibition of photosynthesis due to the action of ABA is caused to a great extent by the obstruction of the C-3 pathway and reduced activity of RuBP carboxylase, whereas (β-carboxylation was not blocked.

A Possible Role for Abscisic Acid in Coupling Stomatal Conductance and Photosynthetic Carbon Metabolism in Leaves

1982 ◽  
Vol 9 (4) ◽  
pp. 489 ◽  
Author(s):  
I.R Cowan ◽  
J.A Raven ◽  
W. Hartung ◽  
G.D Farquhar
Keyword(s):  
Abscisic Acid ◽  
Time Constant ◽  
Carbon Metabolism ◽  
Free Space ◽  
Leaf Tissue ◽  
Guard Cells ◽  
Stomatal Movement ◽  
Photosynthetic Carbon ◽  
Photosynthetic Carbon Metabolism ◽  
Chloroplast Stroma

Data on pH in free space, cytoplasm, chloroplasts and vacuoles in leaf tissue are used to calculate the distribution of abscisic acid (ABA) amongst these compartments, assuming that the intervening membranes are permeable to undissociated ABA only. Data on the permeability of membranes to ABA are used to calculate the time constant for equilibration between the free space and the other components. It is concluded that changes in pH in the chloroplast stroma due to irradiance, or other factors, will change the amount of ABA available to the guard cells via the free space, and that the time constant is similar to that for light-induced stomatal movement. The possibility that such changes play a role in modulating stomatal aperture is discussed.

scholarly journals The effects of lead on the gaseous exchange and photosynthetic carbon metabolism of pea seedlings

2014 ◽  
Vol 56 (1) ◽  
pp. 127-137 ◽  
Author(s):  
Jerzy W. Poskuta ◽  
Eugeniusz Parys ◽  
Elżbieta Romanowska
Keyword(s):  
Carbon Metabolism ◽  
Lead Chloride ◽  
Gaseous Exchange ◽  
Pb Contamination ◽  
Pisum Sativum L ◽  
Pea Seedlings ◽  
Photosynthetic Carbon ◽  
Dependent Inhibition ◽  
Photosynthetic Carbon Metabolism ◽  
Pb Concentration

Roots of whole 3 week-old pea seedlings (Pisum sativum L.) var. "Bordi" were immersed for 24 h in solutions of lead chloride at Pb copcentrations of 200, 400, 800,12000 mg dm3. Accumulation of lead in roots was independent of the Pb concentration, whereas the accumulation of Pb in shoots was an almost linear function of the concentration of this element in the root medium. This treatment caused Pb concentration-dependent inhibition of apparent photosynthesis (APS), photorespiration (PR), <sup>14</sup>CO<sub>2</sub> uptake, stomatal opening and transpiration of shoots and also germination of seeds. The most sensitive to Pb contamination was CO<sub>2</sub> exchange, then transpiration and to a lesser degree germination of seeds. Lead caused a considerable alteration of photosynthetic and photorespiratory carbon metabolism, restricted the <sup>14</sup>C-labeling of: phosphoglycerate, ribose+ribulose, sucrose, glycolate and glycine+serine. Under conditions of C0<sub>2</sub> uptake limited by lead, an enhancement of the <sup>14</sup>C-labeling of malate+citrate, alanine and glucose was observed.

Effects of Cytosolic FBPase on Photosynthetic Carbon Metabolism Under High CO2 Conditions

2008 ◽  
pp. 895-899 ◽  
Author(s):  
Masahiro Tamoi ◽  
Yoshie Hiramatsu ◽  
Shigeki Nedachi ◽  
Tomoki Tabuchi ◽  
Kumi Otori ◽  
...  
Keyword(s):  
Carbon Metabolism ◽  
High Co2 ◽  
Photosynthetic Carbon ◽  
Photosynthetic Carbon Metabolism ◽  
Cytosolic Fbpase
Sign in / Sign up

Export Citation Format

Share Document