Soil and leaf samples were collected on forty rubber plantations on different soil units under varied environmental conditions in the State. Leaf samples were collected during the summer and fall and soil samples in the summer, in 1984 and 1985. The soils were consistently low in P for most plantations and in K for rubber growing in the Atlantic coastal region soils. There was a large variability concerning soil acidity. Base saturation was low in the coastal region soils and in the medium - textured Dark Red Latosol, but high in the Dusk Red Latosol and Podzolic soils over calcareous sandstone. The type of soil affected leaf Fe and B concentrations. Micronutrient deficiencies or excesses were not observed except on three farms where visual symptoms of Zn deficiency were associated whith leaf concentrations bellow 20 ppm. Productivity above, 1,000kg/ha of dry rubber was associated with higher N and K concentrations in the leaves compared to leaves of plantations yielding less than 1,000kg/ha. The leaf concentrations of P, Ca, Mg, and S were not significantly different for groups of high, medium or low productivity.
rubber; Hevea brasiliensis; foliar diagnosis; soil fertility; nutrient survey