EFFECT OF ZINC FERTILIZATION ON PLANT ZINC CONCENTRATION OF FORAGES AND CEREALS

Abstract

Field experiments were conducted in Prince Edward Island (P.E.I.) to determine the effects of Zn (zinc sulfate) applied to the soil; applied as a foliar spray; and the effects of chelated Zn applied as a foliar spray on Zn concentration of alfalfa (Medicago sativa L.), ryegrass (Lolium multiflorum Lam.), wheat (Triticum aestivum L.), and barley (Hordeum vulgare L.). Plant tissue Zn levels as low as 12 mg kg−1 in forages, 14 mg kg−1 in cereal boot stage tissue and 19 mg kg−1 in cereal grain were not related to Zn deficiency. Tissue Zn levels as high as 123 mg kg−1 in barley boot stage tissue and 153 mg kg−1 in alfalfa did not result in yield reduction or any Zn toxicity symptoms. Cereal and forage yields were not affected by Zn treatments. In most cases, soil and foliar Zn applications were effective in increasing the Zn concentration in forages and cereals. Should a Zn deficiency be suspected (either from the crop or animal nutrition viewpoint) Zn could be applied to the soil at 20 kg ha−1 or as a foliar spray at 0.5 to 1.0 kg ha−1 to overcome the problem in this region (and in other areas with similar soil and climatic conditions). Key words: Plant Zn, soil and foliar applied Zn, Zn chelate and zinc sulfate, podzol soils