The Functional State of the Photosynthetic Apparatus of Potato Plants upon Destruction of the Tubulin Cytoskeleton

We have investigated the effect of colchicine, a disrupting agent of the tubulin cytoskeleton, on chlorophyll fluorescence parameters, the Hill reaction, noncyclic photophosphorylation, and the lipid peroxidation reaction in Solanum tuberosum grown in soil in a greenhouse environment. The destruction of microtubules caused an increase in the content of lipid fatty acid hydroperoxides, the primary product of lipid peroxidation, and led to changes in fluorescence parameters: F0 increased, Fm and the maximum quantum efficiency of PSII (Fv/Fm) decreased, and the dissipation of electronic excitation energy as heat increased. Simultaneously, it was found that the Hill reaction rate and the intensity of the process of noncyclic photophosphorylation decreased. The results obtained in this work are discussed in view of the destruction of the integrity of the chloroplast membrane and changes in chlorophyll fluorescence parameters due to colchicine application, as well as in light of our previously obtained data on the change in the content of phytohormones and their concentration ratios in potato leaves when microtubules are destroyed.