Coated KCl increases barley K uptake in two Alberta soils in a greenhouse experiment

An experiment was conducted in the greenhouse on two K-responsive soils to determine the effectiveness of coated and non-coated KCl for barley (Hordeu m vulgare L. 'Duke'). KCl granules, non-coated and coated with 2.5% and 3.5 % polyurethane, were applied at 44 and 132 mg K per pot containing 2000 g o f soil. Plant dry matter, K concentration and K uptake were determined on s hoot samples taken 40 and 76 d after sowing. While dry matter was unaffecte d, coated KCl generally reduced plant K concentration and K uptake at 40 d and increased plant K concentration and K uptake at 76 d. We concluded the KCl coated with polyurethane can be more available to crops in K deficient soils.