Ammonium nitrate limestone (ANL), ammonium sulphate, Chilean nitrate and urea at rates of 75, 150, 225 and 300 kilograms of nitrogen per hectare, splitted in 1, 2, 3 and 4 applications were used in field experiments with coffee trees, in two soils: in a Red Latosol in Ribeirão Preto and in a Red Yellow Ortho-Podzolic in Mococa, Sate of São Paulo, Brazil. In Ribeirão Preto, the experiment was set up in December 1957 and the grain yields were recorded from 1960 to 1969. In Mococa, the experiment was set up in 1960 and the grain yields were recorded from 1962 to 1971. The grain yields of coffee increased with the increases in the nitrogen rates applied. The yield responses to high nitrogen rates were greater in the Red Yellow Ortho-Podzolic soil than in the Red Latosol. Ammonium sulphate and ANL resulted in better yields than Chilean nitrate in the Red Yellow Ortho-Podzolic soil. Urea increased coffee yields above those obtained with Chilean nitrate, but the differences were not significant. No significant effects of nitrogen sources were observed in the Red Latosol. The practice of splitting the total quantities of nitrogen did not affect the grain yields of coffee in the Red Latosol. In the Red Yellow Ortho-Podzolic soil, grain yields were higher when nitrogen was splitted in four applications.
coffee; fertilization; fertilizers; nitrogen (N); urea; ammonium sulphate; Chilean nitrate; ammonium nitrate limestone; rates; splitted applications