Conilon coffee (Coffea canephora) is very important for the economy of the state of Espírito Santo and its organic cultivation is increasing. However, there is a lack of information on leaf reference values for this form of management, as well as a nutritional diagnosis. The objective of this study was to establish and compare reference patterns and to propose adequate values of leaf nutrient concentrations obtained on high yielding conilon coffee plantations, cultivated under organic or conventional systems, in the northern area of Espírito Santo State. Leaf concentrations of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn were determined in plantations under conventional and 56 plantations under organic cultivation. To establish DRIS norms, the data of 23 plantations under conventional cultivation and 22 organic plantations were used. The established norms were compared by the Student "t" test at 1 % probability. Organic and conventional plantations were diagnosed through DRIS norms with the incorporation of dry matter data in the analysis. The frequency of the nutrients with the most negative or most positive index was verified. The most frequent nutrients with more negative DRIS index on the organic plantations were Mn, Cu, N, and P. In the conventional plantations, the most frequent nutrients with more negative index were Mn, Cu and P. The results suggested that each cultivation system should be diagnosed by specific DRIS norms.
Coffea canephora; DRIS; nutritional diagnosis; nutritional balance
