Dry Mass of Shoot and Nodulation of the Pigeon Pea Fertilized with Reactive Rock Phosphate on the Oxisol

摘要

Among the most used crop stands out the pigeon pea ( Cajanus cajan ) that promotes biological nitrogen fixation, having the phosphorus a crucial role in this reaction. The objective was to evaluate the dry mass of shoot and pigeon pea nodulation, in function of phosphorus doses, using as source the reactive rock phosphate Bayovar in Oxisol in the Brazilian Cerrado. The experiment was conducted in a greenhouse for 72 days. Pots containing 3.5 dm3 of soil collected at a depth of 0.0 to 0.20 m in native Cerrado area were used. The experiment design was completely randomized, with seven doses of phosphorus (P₂O₅): 0,100, 200, 300, 400, 500 and 600 mg dm-3 with four replications. Maximum dry mass of shoot production, dry mass of nodules, and number of nodules were observed in the doses of phosphorus (P₂O₅) of 430, 400 and 500 mg dm-3, respectively. The fertilization with reactive rock phosphate Bayovar increases the shoot production and nodulation of pigeon pea.