Nutrição mineral e crescimento de mudas de mamoeiro em função de fósforo e magnésio

• Ano de defesa: 2005
• Autor(a) principal: Vichiato, Marcelo
• Orientador(a): Silva, Carlos Ramirez de Rezende e
• Banca de defesa: Paula, Miralda Bueno de, Alvarenga, Ângelo Alberico, Cunha Neto, Francisco Rodrigues da
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Lavras
• Programa de Pós-Graduação: Programa de Pós-Graduação em Agronomia/Fitotecnia
• Departamento: Departamento de Agricultura
• País: BRASIL
• Palavras-chave em Português: Fruticultura; Nutrição mineral; Variedade; Fruit growing; Mineral nutrition; Variety
• Área do conhecimento CNPq: Ciências Agrárias
• Link de acesso: https://repositorio.ufla.br/handle/1/3374

The influence of both phosphorus and magnesium and their possible interaction upon the growth, contents and accumulation of nutrients in papaya seedlings were evaluated. The experiments were carried out at the horticulture sector of the Lavras Federal University (UFLA), in a nursery fitted with a plastic cover, conducted in randomized block design with five doses of phosphorus (20, 150, 300, 450 and 600 mg.dm-3) and four doses of magnesium (0, 15, 30 and 60 mg.dm-3); in a factorial scheme with four replicates. The plots were made up of five plants, grown singly in plastic bags of 7,0 x 18,5 cm and filled with 635 cm-3 of substrate. In cultivar ISS 72/12, the doses of P and Mg increased all the growth characteristics, interactions between P and Mg on the plant height being found. The contents of N in the shoot dry biomass (SDBM) decreased, the other nutrients being influenced by P-Mg interactions. Growing accumulations of all nutrients in response to the doses of P and Mg were observed. In cultivar Tainung nº 1, the doses of P provided increases in all the growth characteristics, reduced the contents of , K, Ca, Mg and S and increased those of Mn, the contents of P, B, Cu and Zn being influenced by interactions between P and Mg. The doses of Mg affected only the root dry biomass, raised the contents of K and Mn and decreased those of Ca, not influencing those of N, Mg, S and Fe. Increasing accumulations of all the nutrients in the SDBM in response to the doses of P, the doses of Mg raised the contents of K and decreased the ones of N and Ca. The accumulations of P, B, Cu and Fe were influenced by P-Mg interactions. At 120 days after sowing, the greatest development of the ISS 72/12 plants was obtained at the dose of 600 mg.dm-3 of P associated with 30 mg.dm-3 of Mg, presenting a medium height of 18,9 cm and colo diameter of 8,9 mm, its being in cultivar Tainung nº 1, the dose of 600 mg.dm-3 of P associated with 60 mg.dm-3 of Mg with a medium height of 17,7 cm and diameter of 11,1 mm, the seedlings being apt to field planting. The cultivarISS 72/12 was the most responsive to the doses of P and Mg, showing superior gains in growth relative to Tainung nº 1.