RESPUESTA DEL KING GRASS AL FERTILIZANTE POTASICO Y SU FRACCIONAMIENTO

Abstract

Four K2O levels (0, 100, 100 and 300 kg/ha) and four application frequencies (1, 2, 4, and 5 times/year) were used in a randomized block design and four replications in order to determine King grass response to K fertilization. 400 kg of N/ha fractioned per cut were supplied to all plots and in the sown 150 kg of P2O5/ha were applied. A significative response (P<0,05) to K fertilization was found during the first year after the application of 200 kg of K2O/ha applied 5 times per year (25,3 vs 17 t of DM/ha); during the second year, the control did not differ from 100 and 200 kg of K2O/ha applied once and twice/year nor from 300 kg once/year. In the third year, the differences, in respect with the control, were observed after 200 kg of K2O/ha applied twice/year. K content and extraction increased significatively with the supply of this element. It is concluded that two applications of K at about 200 kg/ha should be utilized.