Data/hora: 11/06/2024 08:26:42

Biblioteca(s): 	Embrapa Amazônia Ocidental; Embrapa Arroz e Feijão.	
Data corrente: 	22/11/2010	
Data da última atualização: 	06/06/2022	
Autoria: 	FAGERIA, N. K.; SANTOS, A. B. dos; MOREIRA, A.; MORAES, M. F. de.	
Afiliação: 	NAND KUMAR FAGERIA, CNPAF; ALBERTO BAETA DOS SANTOS, CNPAF; ADONIS MOREIRA, CPAA; M. F. DE MORAES, ESALQ.	
Título: 	Potassium soil test calibration for lowland rice on an Inceptisol.	
Ano de publicação: 	2010	
Fonte/Imprenta: 	Communications in Soil Science and Plant Analysis, v. 41, n. 21, p. 2595-2601, 2010.	
DOI: 	https://doi.org/10.1080/00103624.2010.514377	
Idioma: 	Inglês	
Conteúdo: 	Potassium (K) plays an important role in many physiological and biochemical processes in plants and its adequate use is an important issue for sustainable economic crop production. Soil test?based K fertilizer recommendations are very limited for lowland rice (Oryza sativa L.) grown on Inceptisols. The objective of this study was to calibrate K soil testing for the response of lowland rice (cv. Ipagri 109) to added K. A field experiment was conducted in the farmers? field in the municipality of Lagoa da Confusão, State of Tocantins, central Brazil. The K rates used were 0, 125, 250, 375, 500, and 625 kg K ha -1 applied as broadcast and incorporated during sowing of the first rice crop. Rice responded significantly to K fertilization during 2 years of experimentation. Maximum grain yield of about 6,000 kg ha-1 was obtained with 57 mg K kg -1 soil in the first year and with 30 mg K kg?1 in the second year. This indicated that at low levels of K in the soil, nonexchangeable K was available for plant growth. Potassium use efficiency designated as agronomic efficiency (kg grain produced/kg K applied) decreased significantly in a quadratic fashion with increasing K level in the soil. Agronomic efficiency had a significantly linear association with grain yield. Hence, improving agronomic efficiency with management practices can improve rice yield.	
Palavras-Chave: 	Inceptisol; Produção de grão.	
Thesagro: 	Análise do solo; Arroz; Oryza sativa; Potássio.	
Thesaurus Nal: 	Grain yield.	
Categoria do assunto: 	F Plantas e Produtos de Origem Vegetal	
Registro original: 	Embrapa Arroz e Feijão (CNPAF)	
Exemplares: 	CNPAF - (30245-1) - UPC - AP - DD - 2010 -  - 2010 - DIS
CPAA - (38100-1) - UPC - AP - DD -  -  -  - DIS