Knowledge on mineral nutrient dynamics in coffee trees is important to identify the period of greatest nutritional requirement by the plant, allowing the improvement of fertilization techniques. The aim of our research was to study Ca and Mg dynamics in coffee fruits from anthesis to maturation and compare it with the dynamics of the same elements in leaves of productive branch leaves. The experiment was carried out with three Arabic coffee varieties (Catuaí Vermelho IAC-99, Rubi MG-1192 and Acaiá IAC-474-19) in three independent trials (low, sufficient and high fertilizer levels), arranged in randomized blocks with two replications using a split-plot scheme in time. The varieties presented the highest Ca and Mg fruit concentrations in the initial growth stage and decreasing concentrations in the stages of fast fruit expansion. In the stages of ceasing fruit growth and fruit formation-maturation little or no variation was observed in the Ca and Mg fruit concentrations. In the 3rd and 4th pair of leaves of the productive branches Ca and Mg concentrations decreased in the beginning of the reproductive period and recovered afterwards. In general, the fertilization levels influenced the Ca and Mg concentration in fruits and leaves of the varieties of Arabic coffee plant throughout the reproductive period. However, Ca and Mg concentrations in leaves and fruits were not only influenced by the fertilizer levels, but by other factors as well that determine the distribution rate of the mineral elements in the coffee plants, such as fruit load.
plant physiology; mineral nutrition
