Effects of Preplantation Phosphate on the Inner Morphology of Sugarcane Leaves

Phosphorus is considered an essential element for sugarcane, assuming great importance in rooting, tillering and final stem yield. In order to evaluate the effects of pre-planting phosphating on the internal morphology of sugarcane leaves, an experiment with the RB867515 variety was carried out in a randomized block design with 4 replications, in a factorial scheme 2x4, being two sources of phosphorus (decanted phosphate and monoammonium phosphate) and four doses of phosphorus (0; 80; 120; 160 kg ha-1 P2O5). At 120, 240 and 362 days after planting the following characteristics were evaluated: Abaxial epidermis thickness, adaxial epidermis thickness, mesophyll thickness, phloem vessel diameter and phloem vessel diameter. Phosphorus doses influenced the development of sugarcane leaf-bearing vessels at harvest. Concentrations above 160 kg ha-1 the P2O5 presented lower mean phloem diameter values in sugarcane leaves. Concentrations with 80 kg ha-1 the P2O5 presented greater xylem diameter in sugarcane leaves.