[Interference of phytohormones and synthetic growth regulator melafen in the control of Ca2+ translocation across the plasma membrane of potato (Solanum tuberosum L) tuber cells].

Interference of phytohormones (jasmonic, gibberellic, and abscisic acids) and synthetic growth regulator melafen on Ca2+ translocation across the membrane of plasma membrane vesicles prepared from dormant potato (Solanum tuberosum L.) tubers was studied. The activity of plasma membrane Ca2+, Mg(2+)-ATPase was stimulated by melafen and jasmonic and gibberellic acids and suppressed by abscisic acid. These agents did not change the passive membrane permeability for Ca2+. The pattern of the effect of melafen on the activity of Ca2+, Mg(2+)-ATPase depended on the presence of phytohormones in incubation medium. When melafen and each phytohormone were simultaneously added to incubation medium, their effects were not additive, which indicates that the effects of the tested compounds on the Ca2+ uptake into the plasma membrane vesicles are interdependent. Apparently, the interaction between the phytohormones and plasma membrane components modulates the response to melafen.