Predicting the oil contents in sunflower genotype seeds using near-infrared reflectance

• Published in: Acta scientiarum. Agronomy 2014-04, Vol.36 (2), p.233
• Main Authors: Grunvald, Anna Karolina, de Carvalho, Claudio Guilherme Portela, Leite, Rodrigo Santos, Mandarino, Jose Marcos Gontijo, Andrade, Carlos Alberto de Bastos, Scapim, Carlos Alberto
• Format: Article
• Language: Spanish
• ISSN: 1679-9275
• DOI: 10.4025/actasciagron.v36i2.17677

The aim of this experiment was to calibrate the NIR spectroscopy equation to evaluate the oil content of sunflower seeds from different genotypes produced under different environmental conditions in Brazil. The spectra of 901 standard samples obtained from 88 hybrids and 116 lines, which were evaluated in 11 locations, were collected from intact seeds (achenes) and correlated with data generated by nuclear magnetic resonance analysis. The calibration was determined by linear regression using partial least squares to estimate the parameters. The goodness of fit was evaluated using the coefficient of determination ([R.sup.2]), standard error of calibration (SEC) and the standard error of performance (SEP). The wavelengths ranging from 1319 to 1760 nm were selected for the calibration. The [R.sup.2] was 0.87, the SEC was 2.39, and the SEP was 1.97. The oil content values obtained for the 19 hybrid seeds analyzed by NIR spectroscopy that were not included in the calibration were similar to the values obtained using the chemical method. The similarities between the values obtained using both methods and the [R.sup.2], SEC and SEP values indicated that it is possible to establish a calibration equation using NIR spectroscopy to determine the oil contents of sunflower seeds produced under Brazilian field conditions. Keywords: Helianthus annuus, intact seed, spectral analysis. O objetivo desse trabalho foi estabelecer uma equacao de calibracao pela analise da espectroscopia de NIR para a avaliacao dos teores de oleo em sementes de genotipos de girassol obtidas em condicoes ambientais brasileiras. Os espectros de 901 amostras padroes, provenientes de 88 hibridos e 116 linhagens avaliados em 11 localidades, foram coletados de aquenios intactos e correlacionados com os valores de oleo obtidos por analise de ressonancia magnetica nuclear. A equacao de calibracao foi determinada por regressao linear, cujos parametros foram estimados pelo metodo de minimos quadrados parciais. A precisao foi verificada pelo coeficiente de determinacao ([R.sup.2]), erro padrao de calibracao (SEC) e pelo erro padrao de desempenho (SEP). A regiao de comprimento de onda entre 1319 e 1760 nm foi selecionada para a calibracao. O [R.sup.2] foi 0,87, o SEC foi 2,39 e o SEP foi de 1,97. Adicionalmente, a analise do teor de oleo pelo NIR de 19 hibridos nao incluidos na calibracao foi similar aos valores obtidos no metodo quimico padrao. Esta similaridade e os valores de [R.sup.2], SEC e SEP possib