COFFEE YIELD AND PHOSPHATE NUTRITION PROVIDED TO PLANTS BY VARIOUS PHOSPHORUS SOURCES AND LEVELS

Produtividade e nutrição fosfatada de cafeeiros submetidos a fontes e doses de fósforo

Phosphorus (P) is considered one of the nutrients that most limits crop yields, especially in soils with an advanced degree of weathering. To evaluate P dynamics and availability in soil resulting from various P doses and sources and to assess the resulting P content of coffee leaves and the final coffee yield, an experiment was conducted in the municipality of Três Pontas, MG, Brazil, in a Red Argisol (Ultisol) area. Fertilization, except for P fertilization, was performed based on the soil analysis results. The annual P doses tested were 0, 75, 150, 300, 450 and 600 kg ha^-1 P₂O₅. Two P sources, simple superphosphate and magnesium thermal phosphate, were evaluated and compared in the study. A physicochemical analysis of the soil and an analysis of leaf dry matter were performed. The available P content in the soil increased as a result of the applications of the two sources. The leaf P levels stabilized at approximately 1.8 and 1.9 g kg^-1 for simple superphosphate and magnesium thermal phosphate, respectively, as a result of the application of approximately 300 kg ha^-1 P₂O₅. The coffee responded to P fertilization in the production phase. Averaged over three harvests, the yield per harvest showed gains of 45.3% and 40.3% for simple superphosphate and magnesium thermal phosphate, respectively, with the application of the highest studied dose, 600 kg ha^-1 P₂O₅.

Coffee nutrition; Coffea arabica; phosphorus fertilization