1. [Characteristics of the leaf photosynthetic machinery in broad bean grown in zinc chloride aqueous solutions].
- Author
-
Karavaev VA, Krendeleva TE, Kukarskikh GP, Baulin AM, Poliakova IB, and Tikhonov AN
- Subjects
- Biomass, Chlorophyll analysis, Culture Media, Electron Spin Resonance Spectroscopy, Fabaceae chemistry, Fluorometry, Light-Harvesting Protein Complexes, Photosynthetic Reaction Center Complex Proteins metabolism, Plant Leaves chemistry, Plant Leaves physiology, Chlorides pharmacology, Fabaceae physiology, Photosynthesis, Plants, Medicinal, Zinc Compounds pharmacology
- Abstract
The structural and functional characteristics of bean leaves (the content of chlorophyll, the rate of oxygen production, the slow fluorescence induction, and light-induced changes in the EPR signal I from oxidized reaction centers P700+) were investigated to obtain insight into the mechanism of influence of zinc chloride on the photosynthetic apparatus. Seedlings were grown on hydroponic medium containing ZnCl2 at concentrations from 10(-7) to 10(-3) M. At low concentrations of ZnCl2, a decrease in the content of chlorophyll per one unit of leaf mass was observed, while the rate of oxygen production per chlorophyll was increased. High concentrations of ZnCl2 in the hydroponic medium caused the slowed down the plant development and inhibited the light-induced production of oxygen. The changes in biophysical characteristics of leaves the parameter FM/FT of the slow fluorescence induction, and kinetics of redox transients of P700 induced by ZnCl2 were of similar character and correlated with the changes in photosynthetic activity. The data obtained demonstrate that structural and functional changes in the photosynthetic apparatus induced by the variations of growth conditions have adaptive character.
- Published
- 2001