CRESCIMENTO E TOLERÂNCIA DE MUDAS DE Enterolobium contortisiliquum Vell. CULTIVADAS EM SOLO CONTAMINADO COM ZINCO

Zinc is an essential element to plants, but when present in high concentrations in the soil can become toxic to the plant metabolism. The study aimed to determine the growth and tolerance of Enterolobium contortisiliquum Vell. seedlings cultived in soil contaminated with zinc. The experiment was conducted in a greenhouse in soil with 81% clay, in a completely randomized design with seven treatments, doses of zinc (0, 100, 200, 300, 400, 500 and 600 mg kg-1) eight repetitions. We evaluated the plant height, stem diameter, shoot dry mass, root dry mass, length of the main root, specific surface area, Zn content in shoots and roots, the impact coefficient of relative zinc content, translocation and tolerance. The coefficient of impact of the relative zinc content indicated a trend of lower translocation of Zn to the aerial part of the molt up to the dose of 300 mg of Zn kg-1 of soil. The results showed that doses close to 200 mg Zinc kg-1 clay soil stimulate plant height, stem diameter, stem and root dry mass of seedlings and timbaúva. Timbaúva presents high tolerance to zinc and because it is a native tree adapted to Brazilian environmental conditions it can be indicated for revegetation of contaminated areas with the application of up to 600 mg of zinc kg-1 of clay soil