Macronutrients in production of Peltophorum dubium (Spreng.) Taub. seedlings in red yellow ultisol of the Zona da Mata, MG region

O objetivo deste trabalho foi avaliar o efeito de doses de macronutrientes sobre o crescimento e os \uedndices de qualidade de mudas de canaf\uedstula e determinar a dose recomendada dos mesmos para estabelecer um adequado programa de aduba\ue7\ue3o. No trabalho, conduzido em casa de vegeta\ue7\ue3o, utilizou-se amostras de Argissolo Vermelho Amarelo, retirado da camada abaixo de 20 cm de profundidade, como substrato. Delimitou-se o experimento por meio de matriz baconiana, avaliando-se tr\ueas doses dos seis macronutrientes (nitrog\ueanio, f\uf3sforo, pot\ue1ssio, c\ue1lcio, magn\ue9sio e enxofre) e dois tratamentos adicionais, um com doses de refer\ueancia e outro sem adi\ue7\ue3o de nutrientes. Adotou-se o delineamento inteiramente casualizado com quatro repeti\ue7\uf5es. Foram analisados os par\ue2metros morfol\uf3gicos e os \uedndices de qualidade de mudas. Verificou-se, atrav\ue9s de an\ue1lise dos contrastes ortogonais, resposta significativa de todas as vari\ue1veis estudadas \ue0 aplica\ue7\ue3o dos macronutrientes, exceto para a rela\ue7\ue3o altura di\ue2metro (H/D) nos tratamentos com P, Ca e S. N\ue3o foi verificada resposta \ue0 aplica\ue7\ue3o de Ca para a maioria das caracter\uedsticas avaliadas, com exce\ue7\ue3o das rela\ue7\uf5es altura de parte a\ue9rea por peso de mat\ue9ria seca de parte a\ue9rea (H/MSPA) e peso de mat\ue9ria seca de parte a\ue9rea por peso de mat\ue9ria seca de raiz (MSPA/MSR). Recomenda-se a aplica\ue7\ue3o de 600 mg dm-3 de P, 150 mg dm-3 de K, 0,50 cmolc dm-3 de Mg e 50 mg dm-3 de S, e sugerem-se novos estudos com os nutrientes N e Ca, para a produ\ue7\ue3o de mudas de canaf\uedstula, usando a camada abaixo de 20 cm de profundidade de Argissolo Vermelho Amarelo como substrato.The objective of this work was to evaluate the effect of macronutrients doses upon the growth and quality indices of Peltophorum dubium seedlings and to determine the recommended doses for them to establish a suitable fertilization program. In the paper, carried out in a greenhouse, samples of \u2018Red Yellow Ultisol\u2019 were used, removed from the layer below, 20 cm deep, as a substratum. The experiment was designed in a Baconian Matrix, and three doses of the six macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulfur) and two additional treatments were evaluated, one with reference doses and the other one without the addition of nutrients. The entirely casual design was adopted, with four repetitions. The morphologic parameters and quality indices of seedlings were analyzed. Through the orthogonal contrasts, a significant response of all the variables studied was verified related to the macronutrient applied, except for the relation height/diameter (H/D) in the treatments with Ca, P and S. It was not verified response to Ca application for most characteristics evaluated, unless for the relation of the aerial part height per aerial part dry weight (H/MSPA) and aerial part dry weight per root dry weight (MSPA/MSR). The recommended doses were of 600 mg dm-3 of P, 150 mg dm-3 of K, 0,50 cmolc dm-3 of Mg and 50 mg dm-3 of S. Based on this work, further studies are suggested with N and Ca, for seedlings production of the studied species using from the layer below 20 cm deep of the \u2018Red Yellow Ultisol\u2019 as the substratum