Adubação foliar de sulfato de zinco na produtividade e teores foliares de zinco e fósforo de cafeeiros Arábica

Abstract

Aiming to evaluate the dose and application schedule of foliar Zn-sulfate spraying in growing and yield of Arabic coffee Mundo Novo, a field experiment was set up on Distroferric Red Latosol, at the Experimental Station of the EPAMIG in São Sebastião do Paraíso. The statistical design used was randomized blocks in s 4 × 2 factorial scheme with five replications and a 30-plant plot with six central valid plants. Zinc sulfate (ZnSO4) was sprayed under 4 concentrations 0; 0.5; 1.0 and 1.5%, two or four applications per agricultural year. Phosphorus and zinc leaf levels were evaluated for eight years and the yields. It was possible to conclude that there is a positive response to the increasing concentrations of ZnSO4 applied on the leaves in terms of yield, and to Zn levels in the leaves. Four low concentrations sprayings promoted higher yields than two high concentrations. The highest yields were achieved with 10.8 and 12.6 kg ha-1 of ZnSO4, for 2 and 4 yearly applications, respectively. It is suggested as a critical range for the Zn leaves values between 10 and 28 mg kg-1 and for P/Zn ratio, between 100 and 150.