Influence of fertilizers on cassava production under rainfed conditions

Abstract

A fertilizer trial using a local cassava (Manihot esculenta Crantz) cultivar, Maracas Black Stick, was conducted at the El Carmen Station at Centeno on an acid inceptisol soil (Cunupia Clay) to investigate the effect of different rates of nitrogen (N), potassium (K), and phosphorus (P) on the storage root yield of cassava in a three year study during the wet season. The mean results from the three year study showed that the application of fertilizer significantly increased average cassava yield over that of the unfertilized control. Individual applications of N, P, or K fertilizers significantly increased cassava yield. Similar yields were obtained using 400 kg/ha urea (27.1 t/ha) and 200 kg/ha triple superphosphate (26.2 t/ha). Use of 400 kg/ha muriate of potash alone gave cassava yields of 33.4 t/ha. The best yield performance was obtained using 400, 200, 400 kg/ha N, P, and K fertilizer (63.1 t/ha). However, this was similar to the yield obtained with a 400 kg/ha N and K fertilizer (62.8 t/ha). The use of P fertilizer in combination with high levels of N and K fertilizers did not increase cassava yields.