EFFECT OF THE TRACE ELEMENTS MANGANESE AND MOLYBDENUM ON THE LEAF YIELD AND CONTENT OF CARDIAC GLUCOSIDES IN FOXGLOVE, DIGITALIS GRANDIFLORA, MILL
Application of trace elements improved the performance of the plants; increased leaf size, chlorophyll content, yield and amount of cardiac glucosides in the leaves. Soaking seeds in aqueous solutions of manganese sulphate and ammonium molybdate before sowing and foliar spray of plants at the rosette stage with separate aqueous solutions of these elements produced one and half to two times as much glucosides as the control. However, the greatest yield was produced by foliar spray of plants with combined similar solutions at the technically ripe stage followed by Mn or Mo treatments in the first year (treat. 5a,b), which increased the yield and glucosides accumulation two and half to three times as compared to the control.