Effects of nickel and nitrogen soil fertilization on lettuce growth and urease activity

• Autor(a) principal: Oliveira, Thomas Carlos
• Data de Publicação: 2013
• Outros Autores: Fontes, Renildes Lúcio Ferreira, Rezende, Sebastião Tavares de, Alvarez V., Víctor Hugo
• Tipo de documento: Artigo
• Idioma: fra
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://dx.doi.org/10.1590/S0100-06832013000300016; http://www.locus.ufv.br/handle/123456789/17852
• topic: Ammonium nitrate; Urea; Plant nutrition; Lactuca sativa L.

Nickel is a micronutrient involved in nitrogen metabolism and a constituent of the urease molecule. Plant growth and urease activity were evaluated in lettuce (Lactuca sativa L.) grown in soil-filled pots in a 2 x 8 factorial design with two nitrogen (N) sources and eight Ni rates, with five replications. Nitrogen was applied at 200 mg dm^-3 (half the dose incorporated into the soil at seedling transplanting and half top-dressed later) using the sources NH4NO3 (AN) and CO(NH2)2 (Ur). The Ni treatments (0, 2, 4, 8, 12, 16, 24 and 32 mg dm^-3) were applied as NiCl2. The shoot dry-matter yield, leaf urease activity, Ni levels in the lettuce leaves and Ni levels extracted from soil with Mehlich-3 (M-3) and DTPA were determined. In the plants supplied with AN, the shoot dry-matter yield was higher than in those supplied with Ur. There was no difference in shoot dry matter in response to soil-applied Ni. The leaf urease activity increased with Ni application, regardless of the N source. The extractions with M-3 and DTPA were efficient to evaluate Ni availability for lettuce in the Red-Yellow Latosol.