| Sumario: | Non-flowering two-year old Coffea arabica L. (cv.'S.L 34') plants were grown in sand culture and treated with varying combinations of copper and phosphorus. Increases in the number of leaves and flower buds were observed at P levels of 90 to 140 ppm in the presence of Cu levels of 1064 and 5064 ppm which also produced the best plant growth. However, at higher Cu treatments, severe Cu toxicity symptoms were observed as indicated in reduced leaf number. Increasing the concentration of P treatments increased the total chlorophyll content, Leaf-N was decreased at high Cu concentrations in the presence of P. Increases in leaf-P, -K and decreases in leaf-Ca and -Mg resulting in severe deficiency symptoms, were observed at increasing P treatment concentrations. Leaf- and root-P and -Cu were increased at all treatment combinations with the greatest accumulation of these clements appearing in the roots. The tendency towards increased N, P and Cu accamulations in the roots would probably result in an increase in protein synthesis and a subsequent increase in Cu-protein complexes within the roots
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