Abstract
Schizolobium amazonicum (Huber ex Ducke) é uma espécie que possui rápido crescimento, excelente adaptabilidade e, madeira de qualidade. Porém, pouco se conhece a respeito da sua nutrição na fase de mudas. Diante disso, desenvolveu-se experimento em viveiro, com o objetivo de analisar o crescimento inicial do S. amazonicum após adubação com N, P e K. As mudas de S. amazonicum foram produzidas via semente, em canteiro com areia, e transplantadas para sacolas plásticas de 50x40 cm onde permaneceram durante a fase experimental. O delineamento utilizado foi o inteiramente casualizado com solo previamente calcareado e adubado: N = 0, 2,5, 5,0 e 7,5 kg m-3; P2O5 = 0, 3,0, 6,0 e 12,0 kg m-3 e; K2O = 0, 3,0, 6,0 e 12,0 kg m-3, com ureia, superfosfato simples e cloreto de potássio, respectivamente. Para a análise do crescimento foram determinadas as características morfológicas: altura, diâmetro, biomassa das folhas, biomassa do caule, biomassa da raiz e teores de macronutrientes. As doses que possibilitaram o maior crescimento e melhores condições de nutrição para o S. amazonicum foram 7,5 kg m-3 de N; 12,0 kg m-3 de P2O5 e 6,0 kg m-3 de K2O.Palavras-chave: Schizolobium amazonicum; nutrição de plantas; fertilização mineral. GROWTH AND NUTRITION OF Schizolobium amazonicum AFTER FERTILIZATION WITH N, P AND K ABSTRACT: Schizolobium amazonicum (Huber ex Ducke) is a species with fast growth, excellent adaptability and quality wood. However, little is known about its nutrition in the seedling stage. For this, the experiment was carried out in a nursery with the objective of analyzing the initial growth of S. amazonicum seedlings submitted to N, P and K fertilization. The seedlings of S. amazonicum were produced by seed, in a bed with sand and transplanted to plastic bags of 50x40 cm where they remained during the experimental phase. The design was completely randomized with previously limed and fertilized soil with: N = 0, 2.5, 5.0 and 7.5 kg m-3; P2O5 = 0, 3.0, 6.0 and 12.0 kg m-3 and; K2O = 0, 3.0, 6.0 and 12.0 kg m-3, with urea, simple superphosphate and potassium chloride, respectively. For the analysis of growth, the following morphological characteristics were height, diameter, leaf biomass, stem biomass, root biomass and macronutrients were analyzed. The doses that allowed the greatest growth and better nutritional conditions for S. amazonicum were 7.5 kg m-3 of N, 12.0 kg m-3 of P2O5 and 6.0 kg m-3 of K2O.Keywords: Schizolobium amazonicum; plant nutrition; mineral fertilization.