Application of seed-row potash to soils with high available potassium levels

Abstract

A large number of experiments were conducted from 1989 to 1998 on western Canadian prairie soils with barley (124), hard red spring wheat (52), canola (6) and peas (13) to ascertain the response of these crops to seed-row applied KCl fertilizer. All soils contained potassium levels in excess of what is considered a critical level for obtaining a yield response to potassium due to potassium deficiency. Statistically significant yield increases were obtained with thirty percent of the barley trials and twenty percent of wheat trials. Significant yield losses were observed with less than ten percent of the barley trails and less than twenty five percent of the wheat trials and in one canola trial. None of the assessed plant characteristics (days to maturity, plumpness, protein and root rot infection) revealed any significant benefit from application of Cl as either KCl or CaCl2. There appeared to be a strong link between the probability of obtaining a significant response to seed-row applied KCl and barley variety. However, no clearly defined mechanism for the positive or negative responses could be drawn based on the determined parameters.