EFFECT OF FERTILIZATION AND AZOSPIRILLUM INOCULATION ON PANICUM-MAXIMUM SOWN IN RED AND YELLOW FERRALLITIC SOILS

Two experiments were implemented in a green-house to learn the effect of fertilization and Azospirillum inoculation on the performance of Pa nicum maximum sown in red and yellow ferralitic soils. A random block design with 7 replications was used. Treatments were: 0, 20, 40 and 80 kg of N with and without bacteria inoculation. In the first experimen t the inoculation (red ferrallitic soil) and fertilization with 40 kg N showed an accumulated dry matter yield (0.99 g/plant) higher (P < 0. 001) than the control with 40 kg of N (0.78 g/plant) and comparable to the fertilized control with 80 kg of N (0.92 g/plant). The accumulate d nitrogen yield of the bacteria treated treatment and 40 kg of N (13. 78 mg/plant) was statistically similar to the control with 80 kg of N (13.09 mg/plant). In the second experiment (yellow ferrallitic soil) t he inoculation without fertilization (1.42 g/plant) increased (P < 0.0 01) the accumulated dry matter yield in respect to the control without nitrogen (1.03 g/plant). However, fertilization with the dosages test ed did not increase the inoculation response. The accumulated N yield did not vary between the inoculated treatment without fertilization (2 0.80 mg/plant) and the control with 40 kg of N (19.80 mg/plant). Guine a grass performance was not the same in the soils studied since a fert ilization of 40 kg of N was needed only in the red ferrallitic soil. H owever, in both soils a part of the chemical fertilization was substit uted. It is recommended to evaluate these results under field conditio ns.