Influência de doses de níquel sobre o crescimento de mudas de aroeira (Myracrodruon urundeuva Fr. All.) em solução nutritiva

Abstract

Seedlings of Myracrodruon urundeuva were cultivated in Hoagland and Arnon nutrient solution with Ni 2+ levels: 0; 2,5; 5; 10; 15 and 20 mg Ni2+ L-1 for 40 days. Evaluations of the parameters plant height, stem diameter and root, stem and leaves dry matter production showed significant reduction with increase of Ni2+ levels, except for the stem diameter. The treatment with 2,5 mg Ni2+ L-1 reduced 40% of the plant height and 48% of the total dry matter production; the level of 20 mg Ni2+ L-1 caused the death of the plants. The critical level of Ni toxicity was 1,02 mg L-1. It is also described the symptoms of Ni toxicity.