Título:	Agronomic efficiency of potassium fertilization in lettuce fertilized with alternative nutrient sources.
Autoria:	SILVA, D. R. G. MARCHI, G. SPEHAR, C. R. GUILHERME, L. R. G. FAQUIN, V.
Afiliação:	DOUGLAS RAMOS GUELFI SILVA, UNIVERSIDADE FEDERAL DE LAVRAS GIULIANO MARCHI, CPAC CARLOS ROBERTO SPEHAR LUIZ ROBERTO GUIMARÃES GUILHERME, UNIVERSIDADE FEDERAL DE LAVRAS VALDEMAR FAQUIN, UNIVERSIDADE FEDERAL DE LAVRAS.
Ano de publicação:	2013
Referência:	Revista Ciência Agronômica, v. 44, n. 2, p. 267-277, abr./jun. 2013.
Conteúdo:	The aim of this study was to evaluate the effect of alternative sources of nutrients on the nutrition, yield and efficiency of potassium fertilization in lettuce. The experiment was carried out in a greenhouse, using 3.7 kg pots filled with a dystrophic red-yellow Latosol of medium texture. The experimental design was randomized, with treatments divided into a 4 x 6 factorial: four doses of potassium (0; 200; 400; 600 kg ha-1 K2O) and six alternative sources of nutrients (breccia, ultramafic, biotite schist, phlogopite, and mining and Chapada by-products), with four replications. Content and accumulation were determined for potassium (K), copper (Cu), zinc (Zn) and nickel (Ni) in the lettuce shoots, and from these data two indices were calculated for the efficiency of potassium as a fertilizer. The application of increasing values of alternative sources of nutrients promoted improvements in nutrition and increases in lettuce yield. The efficiency of potassium fertilization decreased with the increase in values of potassium taken from alternative nutrient sources, with the mining by-products and the ultramafic being superior to the other sources. Crushed silicate rocks and mining by-products can therefore both be used as fertilizer in organic and conventional production systems.
Thesagro:	Adubação Alface Lactuca Sativa
NAL Thesaurus:	Lettuce Fertilizers
Palavras-chave:	Rochas silicáticas Silicate rocks Mining by-products
Digital Object Identifier:	https://doi.org/10.1590/S1806-66902013000200008
Tipo do material:	Artigo de periódico
Acesso:	openAccess
Aparece nas coleções:	Artigo em periódico indexado (CPAC)