The influence of temperature on the fatty acid composition of the oils from conventional and high oleic sunflower genotypes grown in tropical regions was evaluated under various environmental conditions in Brazil (from 0° S to 23° S). The amounts of the oleic, linoleic, palmitic and stearic fatty acids from the sunflower oil were determined using gas chromatography (GC). The environment exhibited little influence on the amounts of oleic and linoleic fatty acids in high oleic genotypes of sunflower. In conventional genotypes, there was broad variation in the average amounts of these two fatty acids, mainly as a function of the minimum temperature. Depending on the temperature, especially during the maturation of the seeds, the amount of oleic acid in the oil of conventional sunflower genotypes could exceed 70 %. Higher temperatures led to average increases of up to 35 % for this fatty acid. Although the minimum temperature had the strongest effect on the fatty acid composition, locations at the same latitude with different minimum temperatures displayed similar values for both oleic acid and linoleic acid. Furthermore, minimum temperature had little influence on the amounts of palmitic and stearic fatty acids in the oil.

Adaptability and stability of sunflower genotypes in Central BrazilAbstract -The objective of this study was to evaluate the adaptability and stability of sunflower genotype grain and oil yield, in Central Brazil. The analyzed data were obtained from sunflower genotype trials coordinated by Embrapa Soja, from 2004 to 2007. Genotype adaptability and stability were evaluated using the methods of Eberhart & Russell, Porto et al., Rocha et al., and Annicchiarico. The Annicchiarico method divides sites into favorable and unfavorable environments. This method and the one of Porto et al. were similar and more adequate to evaluate genotypic adaptability. For grain yield, the varieties BRSGira 02 and Nutrissol were widely adapted. The hybrids Agrobel 959, MG50 and V03005 and the varieties Catissol and Multissol were adapted to favorable environments and the hybrids BRHS 02 and BRHS 04 were adapted to unfavorable environments. For oil yield, the hybrids Agrobel 959, V03005, MG50, VDH 487, EXP 1441, EXP 1447, and EXP 1446 and the varieties BRSGira 01, BRSGira 02, and Nutrissol were widely adapted. The hybrid MG52 and the varieties Catissol and Multissol were adapted to favorable environments and BRHS 04 and BRHS 02 were adapted to unfavorable environments. The selected genotypes were shown to be stable, but at different levels.

ABSTRACT. 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 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 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 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.Predição do teor de óleo em sementes de genótipos de girassol por espectroscopia no infravermelho próximo (NIR) RESUMO. O objetivo desse trabalho foi estabelecer uma equação de calibração pela análise da espectroscopia de NIR para a avaliação dos teores de óleo em sementes de genótipos de girassol obtidas em condições ambientais brasileiras. Os espectros de 901 amostras padrões, provenientes de 88 híbridos e 116 linhagens avaliados em 11 localidades, foram coletados de aquênios intactos e correlacionados com os valores de óleo obtidos por análise de ressonância magnética nuclear. A equação de calibração foi determinada por regressão linear, cujos parâmetros foram estimados pelo método de mínimos quadrados parciais. A precisão foi verificada pelo coeficiente de determinação (R 2 ), erro padrão de calibração (SEC) e pelo erro padrão de desempenho (SEP). A região de comprimento de onda entre 1319 e 1760 nm foi selecionada para a calibração. O R 2 foi 0,87, o SEC foi 2,39 e o SEP foi de 1,97. Adicionalmente, a análise do teor de óleo pelo NIR de 19 híbridos não incluídos na calibração foi similar aos valores obtidos no método químico padrão. Esta similaridade e os valores de R 2 , SEC e SEP possibilitaram inferir que é possível estabelecer uma equação de calibração pela espectroscopia de NIR para a avaliação do teor de óleo em sementes de genótipos de girassol cultivados em condições ambientais brasileiras. Palavras-chave:Helianthus annuus, sementes intactas, análise spectral.

RESUMO: O óleo de sementes de genótipos convencionais de girassol apresenta, geralmente, teores de 55 a 65% de ácido graxo linoleico, que pode reduzir o colesterol plasmático total e a fração LDL-colesterol, além de reduzir os riscos de doenças cardiovasculares. Além dos convencionais, genótipos mutantes têm sido obtidos com teores superiores a 80% de ácido graxo oleico, cujo óleo possui maior estabilidade na fritura, além de trazer benefícios à saúde. O objetivo do presente trabalho foi comparar métodos e avaliar a adaptabilidade e a estabilidade de rendimento de grãos e de óleo de genótipos de girassol convencional e alto oleico na Região Sul do Brasil, uma das regiões promissoras para o seu cultivo. Os dados dos componentes de rendimento foram obtidos entre 2008 e 2010, de ensaios conduzidos em delineamento de blocos casualizados, em diferentes locais dos Estados do Rio Grande do Sul e do Paraná. O estudo de adaptabilidade e estabilidade foi feito por meio dos métodos Eberhart e Russell, Rocha et al., Lin e Binns modificado por Carneiro, Annicchiarico, e Porto, Carvalho e Pinto. Os híbridos convencionais V 50070 e Paraíso 20 tiveram adaptabilidade a ambientes favoráveis e desfavoráveis para os dois componentes de rendimento. Os três últimos métodos apresentaram grande similaridade e possibilitaram ainda selecionar genótipos com desempenho em ambientes específicos, mesmo quando não se destacaram na média geral. Os híbridos EXP 1450 (alto oleico) e PARAÍSO 33 (convencional) foram indicados para ambientes desfavoráveis e favoráveis, respectivamente.

This study aimed to evaluate the fatty acid profiles of sunflower oil extracted from hybrid grains produced and stored in different environments. The trials were conducted in Teresina (Piauí), Vilhena (Rondônia), and Jaguariúna (São Paulo) in randomized complete block design with 4 replicates. After harvesting, grains from 1 high oleic and 3 traditional hybrids were packed in kraft paper bags and stored in a covered shed and in a cold chamber up to 12 months. The fatty acid profiles were determined by gas chromatography after 0, 4, 8, and 12 months of storage. Analyses of variance were conducted in a split-plot design, with hybrids being considered as whole plots and storage times as subplots. Tukey's test was performed to compare hybrids and regression analyses for storage times. The initial fatty acid profile of the grains of the same hybrid varied depending on the production location. The grain storage of high oleic and traditional sunflower hybrids during 12 months in covered shed and in cold chamber resulted in little changes in oil fatty acid profiles, regardless of the initial contents. These changes occurred only for linoleic and palmitic acids.