Resumo

RUIZ, C; SANCHEZ, A  e  TUA, D. Effect of the dose and form of placement of the potassium on the concentration foliates of macroelements in the tomato (Lycopersicon esculentum Mill.). Rev. Fac. Agron. [online]. 2006, vol.23, n.2, pp.161-171. ISSN 0378-7818.

The effect of three potassium level was studied; 0.220 and 330 kg^-1, put in three different ways (central, lateral and at the bottom of the furrow) on the foliar concentration of N, P, K, Ca and Mg, measured by spectrophotometry of atomic absorption and using a Perkin-Elmer equipment, model 2280 and the foliar concentration of P was analyzed by photometry using molybdate of ammonium during flowering, filled and fruiting in the tomato cv. Río Grande plant, of the Guarabal area, Falcon municipality, in a soil classified as Haplocambids. A randomized plot design was used with 7 treatments and 6 replications. N was found between ranks from 5.38% and 5.88% in treatments of 330 kg.ha^-1-bottom of the furrow and 330 kg.ha^-1-lateral, respectively. A higher concentration of K was determined during flowering. P varied from 0.29%, 0.14%, and 0.23% during flowering, filled and fructification respectively. The treatments that most accumulated K were the one of 330 kg.ha^-1-central and the other of 330 kg.ha^-1-bottom of the furrow; concentrations of Ca varied from 3.61% to 4.63% in treatments 330 kg.ha^-1-lateral and 220 kg.ha^-1-bottom of the furrow respectively. Regarding Mg, concentrations varied from 0.83% to 1.06 %for treatments of 330 kg.ha^-1-lateral and the witness respectively. The concentration of N, during filling varied from 3.30% to 3.78 % in witness treatments and 220 kg.ha^-1-lateral. P varied from ranks of 0.13% to 0.16% in treatments of 220 kg.ha^-1-bottom of the furrow and from 330 kg.ha^-1-lateral. K was from 2.11% to 2.40% in treatments 220 and 330 kg.ha^-1-bottom of the furrow, respectively, during fruiting significant differences were not found among treatments for concentrations of N, P, K, Ca and Mg.

Palavras-chave : tomato; flowering; clotted; fructification; potassium; macroelements.