ABSTRACT
The content and the ratio of phytohormones, the activity of enzymes-antioxidants and lipid peroxidation, contents of proline and carotenoids in potato plants under the action of colchicines have been investigated. We have identified specific changes in hormonal balance of the plant initiated by the destructor of microtubules, colchicines (1 mM). We have found significant decreased in the amount of indoleacetic acid and zeatin, increase in the content of abscisic acid, no changes in the level of gibberellic acid, a decreased in the ratio between hormones-stimulants and abscisic acid. At this hormonal background, we observed activation of low molecular weight antioxidant system (increased levels of proline and carotenoids), while the peroxidase activity decreased slightly, and catalase activity did not change. Monitoring of reactions of lipid peroxidation showed the activation of its initial stages (accumulation of hydroperoxides), and then the process stabilized (the level of malondialdehyde did not change). We have concluded that the formation of hormonal status Solanum tuberosum, as well as the work of the antioxidant system, depend on the structural condition of the tubulin cytoskeleton.
Subject(s)
Antioxidants/metabolism , Colchicine/pharmacology , Microtubules/metabolism , Plant Growth Regulators/metabolism , Solanum tuberosum/metabolism , Carotenoids/metabolism , Catalepsy/metabolism , Peroxidases/metabolism , Plant Proteins/metabolism , Solanum tuberosum/cytologyABSTRACT
The effects of the antioxidant Ambiol and 2-chlorethylphosphonic acid (2-CEPA) on individual concentrations and concentration ratios of phytohormones, photosynthesis and photophosphorylation rates, sucrose and starch content in tubers, and plant productivity were studied in potato (Solanum tuberosum L). Ambiol increased the ratio of indoleacetic acid (IAA) to abscisic acid (ABA), IAA/ABA, and that of zeatin (Z) and zeatin riboside (ZR) to ABA, (Z + ZR)/ABA. These effects were underlain by an increase in the content of auxins and cytokinins and a decrease in ABA. Unlike Ambiol, 2-CEPA increased the level of ABA, the effect being the most pronounced in the tubers. Ambiol increased the rates of photosynthesis and noncyclic photophosphorylation in chloroplasts isolated from potato leaves. The relation of this phenomenon to auxin and cytokinin accumulation, Ambiol- and 2-CEPA-induced changes in the hormonal balance of potato tubers, carbon metabolism, and plant productivity is discussed.
Subject(s)
Antioxidants/pharmacology , Benzimidazoles/pharmacology , Organophosphorus Compounds/pharmacology , Plant Growth Regulators/metabolism , Solanum tuberosum/drug effects , Chloroplasts/metabolism , Phosphorylation/drug effects , Photosynthesis/drug effects , Plant Growth Regulators/analysis , Plant Leaves/drug effects , Plant Leaves/metabolism , Plant Roots/drug effects , Plant Roots/metabolism , Solanum tuberosum/metabolism , Starch/analysis , Starch/metabolism , Sucrose/analysis , Sucrose/metabolismABSTRACT
During ontogenesis of the potato (Solanum tuberosum L.), the content of indoleacetic acid (IAA) in different organs was determined. The dynamics of IAA in the leaves corresponded to changes in photosynthetic activity. The treatment with IAA increased the intensity of photosynthesis. It was shown that the IAA content increased in the leaves and that IAA ascended to the stem basal part in the second half of vegetation. The accumulation of IAA in the stem basal part gave rise to a positive gradient of sugar in the stem, differentiation of stolons and transport of assimilate in the grown tubers. A correlation was found between the content of IAA in tubers and the rate of its growth.
