Crescimento de mudas de Acacia mangium Willd. em resposta a nitrogênio, fósforo e micorriza

• Autor(a) principal: Amezquita, Sandra Patricia Montealegre
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3071
• topic: Nutrição de plantas; Propagação de plantas; Associações simbióticas; Plant nutrition; Propagation of plants; Symbiotic associations; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::SILVICULTURA

The present study aimed to assess the interaction between P and N rates in the greenhouse production of Acacia mangium Willd., seedlings in the presence or absence of native arbuscular mycorrhizal fungi (AMF). The substrate used consisted of a mixture of one quarter of sand and three quarters of Yellow Red Oxisol. The experiment was set in a 2 x 5 x 5 factorial scheme with three blocks, being two mycorrhizal treatments (with and without AMF), five N rates (0, 50, 100, 150 and 200 mg/dm3) and five P rates (0, 100, 200, 300 and 400 mg/dm3). The seeds had their dormancy broken prior to inoculation with Bradyrhizobium BR 3609 + 6009. The height (H), lap diameter (LD), shoot dry matter (SDM), root dry matter (RDM), total dry matter (TDM), SDM/RDM ratio (SRDMR), Dickson s quality index (DQI), mycorrhizal colonization, number and weight of nodules, and nutrient (N, P, K, Ca, Mg, Cu and Zn) content in the TDM were assessed on the 120th day after sowing. Results showed that mineral N and P fertilization improved the quality and the growth of the seedlings. The low effectiveness of the AMF inoculation hindered the expression of the effects of mycorrhiza on the growth and nutrition of the seedlings. Nevertheless, the AMF slightly improved RDM and N content. Rhizobium inoculation was also ineffective and was not influenced by AMF inoculation. The highest dry matter yield was obtained with the application of 307,83 mg/dm³ N and 181,59 mgdm³ P with no AMF inoculation.