Mineral fertilizers for dry beans: V - Effects of N, P, K, Sand a mixture of micronutrients on two soils of the Paraíba Valley

Four fertilizer experiments with dry beans were conducted during the dry period of 1962 in two localities of the Paraiba Valley, State of Sao Paulo. In each locality two trials were located in neighboring areas, one of which was previously limed. Where the trials were conducted without irrigation in a slope, the yields were drastically lowered by the prevailing drought and only favorable responses to phosphorus were observed. However, in the locality where they were located on a lowland with organic soil and subirrigated, the yields reached high levels. While nitrogen, potassium and sulfur did not increase the yields, phosphorus induced large and similar increases in the unlimed as well as in the limed area. Although the responses to a mixture of micro-nutrients (Zn, Cu, B and Mo) were highly favorable in both areas, that obtained in the unlimed one was much higher.