Data/hora: 09/06/2024 16:51:31

Provedor de dados: 	86	
País: 	Brazil	
Título: 	Critical values of nitrogen indices in tomato plants grown in soil and nutrient solution determined by different statistical procedures	
Autores: 	Fontes,Paulo Cezar Rezende; Ronchi,Cláudio Pagotto.	
Data: 	2002-10-01	
Ano: 	2002	
Palavras-chave: 	Lycopersicon esculentum; Nitrogen fertilizers; Plant soil relations; Statistical analysis.	
Resumo: 	The objective of this study was to establish critical values of the N indices, namely soil-plant analysis development (SPAD), petiole sap N-NO3 and organic N in the tomato leaf adjacent to the first cluster (LAC), under soil and nutrient solution conditions, determined by different statistical approaches. Two experiments were conducted in randomized complete block design with four repli-cations. Tomato plants were grown in soil, in 3 L pot, with five N rates (0, 100, 200, 400 and 800 mg kg-1) and in solution at N rates of 0, 4, 8, 12 and 16 mmol L-1. Experiments in nutrient solution and soil were finished at thirty seven and forty two days after transplanting, respectively. At those times, SPAD index and petiole sap N-NO3 were evaluated in the LAC. Then, plants were harvested, separated in leaves and stem, dried at 70ºC, ground and weighted. The organic N was determined in LAC dry matter. Three statistical procedures were used to calculate critical N values. There were accentuated discrepancies for critical values of N indices obtained with plants grown in soil and nutrient solution as well as for different statistical procedures. Critical values of nitrogen indices at all situations are presented.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2002001000010	
Editor: 	Embrapa Secretaria de Pesquisa e Desenvolvimento

Pesquisa Agropecuária Brasileira	
Relação: 	10.1590/S0100-204X2002001000010	
Formato: 	text/html	
Fonte: 	Pesquisa Agropecuária Brasileira  v.37 n.10 2002	
Fonte: 	info:eu-repo/semantics/openAccess