Effect of the use of a hydrogel on the leaching of nitrogen and potassium on winter wheat in a volcanic ash soil

Abstract

On a volcanic ash soil in Valdivia, Chile, a lysimetric study was carried out in order to determine the effect of the use of a hydrogel on water percolation, nitrogen and potassium leaching and some development characters of winter wheat. Twelve lysimeters in random block design, with three treatments and four replicas, were used. Treatments were: without hydrogel-high N dose, with hydrogel-high N dose and with hydrogellow N dose. High and low nitrogen doses correspond to 160 and 80 kg N/ha, respectively. Hydrogel dose was 50 g/lysimeter. There were no differences found in percolated water amounts, nitrogen and potassium leaching, related to treatments. Highest nitrogen and potassium losses occurs in june and july, together with highest rainfall amounts and the lowest plant development. Highest N-dose increases grain yield and dry matter weight of plants, but not harvest index. There were no differences found in grain yield, dry matter weight of plants and harvest index, related to hydrogel treatment.