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Elfadl E.,University of Hohenheim | Reinbrecht C.,Pflanzenzucht SaKa GbR | Claupein W.,University of Hohenheim
Genetic Resources and Crop Evolution | Year: 2010

An investigation was conducted to determine the extent of diversity and relationships among a worldwide safflower (Carthamus tinctorius L.) germplasm collection and to find out adapted accessions that can be used in an organic safflower breeding program in Germany. A total of 468 accessions was studied under organic farming conditions at Kleinhohenheim experimental station during the seasons of 2004 and 2005. All the accessions were evaluated for 12 phenotypic traits and three rated diseases. Multivariate analyses have been used to measure the diversity in a subset of 200 accessions and 11 geographical regions. Generally, the study showed that there was a large genetic variation within accessions. A coefficient of variation (CV%) for investigated traits and diseases ranged from 2.9 to 91.0% with the highest CV was recorded for yield/m2, yield/plant and seeds/plant. The most accessions that originated in Europe revealed relatively better performance compared to non-Europeans. High yielding, early maturing, and disease tolerant accessions were identified. However, the low oil content (8.7-22.8%) is the primary concern in this germplasm collection. The degree of heritability varied between 10% for lodging to 86% for plant height. Genotypic coefficient of correlation (rg) was slightly higher for many traits than the respective phenotypic coefficient. Oil content and seed yield/m2 were highly significantly correlated (rg=0.78). The genotypic coefficient of correlation showed that selection for seeds/plant and thousand kernel weight was effective for improvement of seed yield and oil content. The results of the principal component analysis and the clustering pattern of accessions were consistent with the results of analysis of variance. About 78% of the total phenotypic diversity in the germplasm was explained on the basis of four principal components and 88% of the total variation among geographical regions was contributed by the first three principal components. The distribution of the accessions within clusters has no apparent relationship with the geographical origin. However, many of the European accessions have a tendency to stay together. © Springer Science+Business Media B.V. 2009. Source

Elfadl E.,University of Hohenheim | Reinbrecht C.,Pflanzenzucht SaKa GbR | Claupein W.,University of Hohenheim
International Journal of Plant Production | Year: 2010

The development of NIRS calibration model as a rapid, precise, robust, and cost-effective method to estimate oil content in ground seeds of worldwide safflower germplasm collection grown under different agro-climatic conditions was the key objective of this research project. The oil content was measured by accelerated solvent extraction method in a total of 328 samples collected across 2004 (165 samples) and 2005 (163) growing seasons and used as reference values. Two thirds of the measured samples were used for building the calibrations and one third for the validations. Combined and annual calibration and validation models were carried out by NIRCal 4.21 using the partial least squares (PLS) regression. Different data pretreatments such as full multiplicative scatter correction (MSC), first derivative or smoothing way of Savitzky-Golay with a gap of 9 data points were used to improve the calibration models. The optimum PLS factors for developing the best calibration were 12, 10, and 14 for combined model, annual model of 2004 and of 2005, respectively. In combined and annual models, the statistical parameters in calibration model were consistent with the respective parameters in validation model. Coefficient of variation (15.5 to 25.1) demonstrated high variability in calibration and validation models. The standard error of estimation (SEE) and standard error of prediction (SEP) for combined model were 1.40 and 1.43, respectively. Although the quality value (Q-value) of calibration was slightly higher in annual models (0.66 for both), the combined calibration model (0.64) precisely predicted oil content as indicated by higher coefficient of determination (0.90) and RPD (3.2%) compared to annual calibration. The accuracy and precision of the combined calibration model were sufficient to use NIRS as a tool for screening of oil content in a diverse safflower germplasm in the range obtained. Source

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