Sintomas de deficiências nutricionais em mudas de mogno cultivadas em solução nutritiva

Abstract

Mahogany (Swietenia macrophylla) is one of the most expensive wood species in the world, but its uncontrolledexploration has reduced its natural reserves. Therefore, reforestation programs can be an alternative for the continuous use of itswood. However, little is known about its nutritional requirements and for this reason, this work aimed at diagnosing the symptoms ofmacro and micronutrients deficiencies in seedlings of mahogany in the missing element technique. The plants were cultivated innutritive solution and the treatments consisted of the individual nutrients omission - N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn, and incomplete nutritive solution. After 100 days from the beginning of the treatments, the symptoms were described and photographed; theplants were collected, washed, separated in roots and aerial parts, dried and weighed for dry mass determination. In general, thevisual symptoms of nutrients deficiencies were easily characterized, except for the -S, -Zn, -Mg and P treatments, in the omission ofthe other nutrients there was a reduction in the production of total dry mass, especially in the N, K, Ca and Cu omission indicatedlarger demand of these nutrients in the initial phase of the plant development.