IMPROVEMENT OF FOXGLOVE PLANT PRODUCTIVITY BY GROWTH-REGULATOR APPLICATION

The influence of some growth regulators (gibberellic acid, chlorocholi ne chloride, and Kamposan-M extra) on the accumulation of cardiac glyc osides by Digitalis lanata Ehrh. and Digitalis purpurea L. plants was studied in pot culture, field experiments, as well as in farm trials. In parallel, the content of endogenous phytohormones in the leaves was determined. The two-step treatment of plants with gibberellic acid ea rly in development to stimulate, growth and then with ethylene-produce r Kamposan-M extra at the preharvest period to inhibit growth increase d the yield of cardiac glycosides by 45 - 85%. A difference in hormone content between D. purpurea and D. lanata treated with the growth reg ulators was shown. The developed two-step plant treatment, with growth regulators, enhanced in succession both glycoside yield components, i .e., the production of above-ground biomass of rosette plants and the content of secondary compounds in it.