Data/hora: 07/06/2024 02:50:12

Biblioteca(s): 	Embrapa Agricultura Digital.	
Data corrente: 	05/05/2009	
Data da última atualização: 	01/12/2010	
Autoria: 	STRECK, N. A.; BOSCO, L. C.; LAGO, I.	
Afiliação: 	NEREU AUGUSTO STRECK, UFSM; LEOSANE CRISTINA BOSCO, UFSM; ISABEL LAGO, UFSM.	
Título: 	Simulating leaf appearance in some Brazilian spring wheat genotypes.	
Ano de publicação: 	2007	
Fonte/Imprenta: 	Revista Brasileira de Agrometeorologia, Piracicaba, v. 15, n. 1, p. 95-102, 2007.	
Idioma: 	Inglês	
Conteúdo: 	The calculation of leaf appearance rate (LAR) is an important part of many wheat simulation models. The strength of a crop simulation model is how well it works under a wide range of different environments and with different genotoypes. This study evaluates the performance of an existing model recently developed for winter wheat (the Streck LAR model) in simulating the main stem LAR and Haun Stage of some Brazilian spring wheat cultivars. The Streck LAR model is composed of three non-linear response functions combined in a multiplicative fashion, and model coefficients have biological meaning and operational definitions. The original and modified version of the Streck LAR model were used in this study. The modified version of the Streck LAR model consisted of adapting two coefficients for local cultivars. A field experiment was carried out at Santa Maria, RS, Brazil, which provided independent data for evaluating the two versionis of the Streck LAR model. Thirteen Brazilian wheat cultivars were sown on 05 July 2003, and the number of main stem leaves, represented by the Haun Stage, was measured weekly. The original version of the model overpredicted most of the Haun Stage data, with an overall (including data for all cultivars) root mean square error (RMSE) of 1.5 leaves. Simulations were greatly improved with the modified version of the model, decreasing the overall RMSE to 0.8 leaves. RMSE lower than one leaf was obtained with the Modified Streck LAR model for ten out of the thirteen spring wheat cultivars evaluated.	
Palavras-Chave: 	Genótipos de trigo de primavera; Modelo; Número de folhas; Simulação do aparecimento de folhas; Simulation; Temperatura do ar.	
Thesagro: 	Triticum Aestivum.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Agricultura Digital (CNPTIA)	
Exemplares: 	CNPTIA - (12874-1) - ADD - AP - PP -  -  -  - DIS