Avaliação da qualidade de mudas de castanha do Brasil submetidas à ausência de nutrientes

Abstract

Bertholletia excelsa is a species of Amazonian region. Its importance is related to the income generated by activities of production and marketing of chestnut fruits and the wood logging. The wood has optimal national and international acceptation.and possible to use in reforestation programs. However, there are few studies regarding the silviculture and mainly the nutritional requirements of the species. In order to assess nutritional aspects and the effect of lacking nutrients during the development of Bertholletia excelsa seedlings, an experiment was conducted on pots in a red latosol of low natural fertility in a greenhouse. Twelve treatments were applied with the technique of missing nutrient in completely randomized blocks with seven repetitions. The following treatments were adopted: complete 1 (C1 – fertilized with N, P, K, S, B, Cu, Fe, Zn and liming), complete 2 (C2 – fertilized with N, P, K, S, Ca, Mg, B, Cu, Fe, Zn, without liming), complete treatments missing one nutrient (complete 1 -N, complete 1 -K, complete 1 -S, complete 1 -P, complete 1 - B, complete 1 -Zn, complete 1 – liming, complete 2 -Ca, complete 2 -Mg) and control. The studied characteristics were: stem diameter, plant height, dry biomass of the stem, dry biomass of leaves, dry biomass of the over ground parts, dry biomass of root, total biomass, relationship root/over ground, stem height/diameter and Dickson index. The analysis of results allowed us concluding that the most limiting nutrients for the growth of Bertholletia seedlings were boron and phosphorus and the less limiting was sulfur.