An experiment was carried out to study the effects of nitrogen, phosphorus and potassium fertilizations on dry rubber yield of Hevea brasiliensis Muell Arg., clone PB 235 growing on a Dark Red-Yellow Latosol, in Garça-SP, Brazil. The experiment consisted of a (1/4)43 fractional factorial of randomized block design, with 16 treatments and 4 replicates, utilizing 4 levels of N (0, 80, 160 and 320 kg ha-1), 4 of P2O5 (0, 40, 80 and 160 kg ha-1) and 4 of K (0, 80, 160 and 320 kg ha-1). The rubber yield was evaluated monthly from October 1995 to June 1996. Results showed that potassium fertilization increased dry rubber yield, which was not affected by nitrogen and phosphate fertilizations.
rubber tree; NPK; fertilization
