EFFECT OF CALCIUM SILICATE SUPLLY AND THE NUTRITIONAL EFFICIENCY OF COFFEE CULTIVARS

Silicon is classified as a beneficial nutrient and can improve the nutritional dynamics of plants, although it is not considered an essential nutrient for plants. In an experiment in a randomized block design, three coffee cultivars (Catuai, Mundo Novo and Icatu) were planted in plastic tubes, combined with six doses of calcium silicate (T-0=0, T-1=0.063, T-9=0.125, T-3=0.25, T-4=0.5 and T-5=1.0 g dm(-3) substrate), to compare the nutritional efficiency of the cultivars in response to silicon fertilization. Cultivar Icatu showed the higher uptake efficiency (UE) of Cu, Zn, Fe, and Si, and efficiency of use (EU) of N, K, Ca, B, and Mn, but the later did not differ from Mundo Novo cultivar (N, Ca, and Mn). The efficiency of translocation (ET) was higher for N, S, Zn, and Fe. For Catuai the uptake efficiency of P, K, B, and Mn was higher, but did not differ from Mundo Novo for P, K and Mn. The Catuai's s efficiency of use for Mg, S, Cu, Zn, Fe, and Si was higher, probably because of a better ET of these nutrients, with exception of Fe and Si. The cultivar Mundo Novo was the most efficient in N, K, Ca, Mg, Mn and Si uptake, had the higher EU of P and Mn, and the highest ET of K, Ca, B, Mn, and Si.