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Stuttgart Mühlhausen, Germany

Montes J.M.,JatroSelect GmbH | Bulach A.,University of Hohenheim | Martin M.,JatroSelect GmbH | Senger E.,JatroSelect GmbH
Bioenergy Research | Year: 2015

Jatropha curcas L. (jatropha) is an undomesticated plant with a high potential for sustainable production of biofuels in the tropics and subtropics. Oil content, seed mass, kernel mass, and the ratio of kernel to seed mass are important traits for breeding. These traits could potentially be improved by exploitation of parental effects. Besides, parental effects could be used to separate self- from cross-fertilized seeds and increase the efficiency of hybrid seed production. The main goal of this study was to assess the variation of quantitative seed traits (oil content, seed mass, kernel mass, and ratio of kernel to seed mass) in a panel of self- and cross-fertilized seeds from a genetically diverse germplasm. We analyzed a set of 31 genotypes (12 self- and 19 cross-fertilized genotypes) originated by combination of parental components from 2 different genetic pools (pool A: phorbol ester absence; pool B: phorbol ester present). We found strong significant effects of parental components and genetic pools on most seeds traits. Although the variation in oil content among single seeds was very large, some specific combinations of parental components showed promise to be exploited for rapid and automatized identification and classification of self- and cross-fertilized seeds. We conclude that parental effects need to be considered for breeding and cultivar production. © 2015, Springer Science+Business Media New York.

Montes J.M.,JatroSelect GmbH | Technow F.,University of Hohenheim | Martin M.,JatroSelect GmbH | Becker K.,JatroSolutions GmbH
Diversity | Year: 2014

Jatropha curcas L. (jatropha) is an undomesticated plant that has recently received great attention for its utilization in biofuel production, rehabilitation of wasteland, and rural development. Knowledge of genetic diversity and marker-trait associations is urgently needed for the design of breeding strategies. The main goal of this study was to assess the genetic structure and diversity in jatropha germplasm with co-dominant markers (Simple Sequence Repeats (SSR) and Single Nucleotide Polymorphism (SNP) in a diverse, worldwide, germplasm panel of 70 accessions. We found a high level of homozygosis in the germplasm that does not correspond to the purely outcrossing mating system assumed to be present in jatropha. We hypothesize that the prevalent mating system of jatropha comprise a high level of self-fertilization and that the outcrossing rate is low. Genetic diversity in accessions from Central America and Mexico was higher than in accession from Africa, Asia, and South America. We identified makers associated with the presence of phorbol esters. We think that the utilization of molecular markers in breeding of jatropha will significantly accelerate the development of improved cultivars. © 2014 by the authors.

Montes J.M.,University of Hohenheim | Montes J.M.,JatroSelect GmbH | Technow F.,University of Hohenheim | Dhillon B.S.,University of Hohenheim | And 2 more authors.
Field Crops Research | Year: 2011

Breeding, genomic, and physiological research on early growth in plants is hampered by the lack of suitable tools for non-destructive phenotyping of the above-ground biomass of a large number of genotypes in field trials. We designed a high-throughput phenotyping platform employing light curtains (LC) and spectral reflectance (SR) sensors mounted on a tractor and evaluated its performance under field conditions. The objectives of our study were to (i) compare biomass determination by LC, SR sensors, and their combination (LC⊕SR) using various biometric methods, (ii) evaluate the effect of the composition of the calibration data set on the mean relative error of prediction (MRE) and coefficient of determination of validation (Rv2), and (iii) assess the repeatability (w2) of biomass determination. Twenty maize genotypes were grown in field trials in five environments. Sensor measurements were taken at three stages (full development of the fourth, sixth and eighth leaf). After recording sensor measurements, plots were harvested to determine fresh biomass. Biomass prediction was based on linear, non-linear and locally weighted polynomial regression for LC measurements. Partial least squares regression (PLSR) and support vector machine regression (SVMR) were used for SR and LC⊕SR measurements. The LC⊕SR data using SVMR and global sampling resulted in the lowest MRE (0.11) and the highest Rv2 (=0.97). Repeatability based on duplicate measurements of each plot was very high. In conclusion, this study provided a proof-of-concept that the described high-throughput, non-destructive phenotyping platform based on LC and SR sensors has a great potential for early biomass determination in field trials of maize and other row-crops. © 2011 Elsevier B.V.

Grieder C.,University of Hohenheim | Mittweg G.,State Institute of Agricultural Engineering and Bioenergy | Dhillon B.S.,University of Hohenheim | Montes J.M.,University of Hohenheim | And 3 more authors.
Biomass and Bioenergy | Year: 2012

Maize (Zea mays L.) is the most competitive crop for methane production in Germany. Methane fermentation yield per unit of dry matter (MFY) is a determinant of methane yield, but little information is available on this trait. Our objectives were to investigate the kinetics of MFY during fermentation of maize, estimate quantitative-genetic parameters for different traits related to MFY and examine the relationship of MFY with chemical composition and silage quality. Whole-plant material of 16 inbreds and their 32 testcrosses was analyzed for MFY over 35 days of fermentation using a discontinuous laboratory assay. Data were also generated on chemical composition and invitro digestible organic matter (IVDOM). Significant genotypic variances and high heritabilities were observed for MFY at early fermentation stages (up to 5 days) probably due to different concentrations of easily degradable chemical components. However, genotypic variances and heritability of MFY reduced as fermentation progressed, because of complete or partial degradation of all chemical components. Further, there were strong correlations of MFY with chemical components at early fermentation stages but not at later stages. Therefore, MFY at later stages, which is closer to potential MFY, does not seem to be amenable to selection. High heritability of IVDOM and its strong correlation with MFY in testcrosses indicated its possible use for preliminary or indirect selection. Keeping in view the magnitude of genetic variance that was low for MFY and high for dry matter yield (DMY), the other component of methane yield, more emphasis on breeding for DMY seems appropriate. © 2011 Elsevier Ltd.

Grieder C.,University of Hohenheim | Mittweg G.,State Institute of Agricultural Engineering and Bioenergy | Dhillon B.S.,University of Hohenheim | Montes J.M.,University of Hohenheim | And 3 more authors.
Journal of Near Infrared Spectroscopy | Year: 2011

Maize (Zea mays L.) is the most commonly used substrate for methane production through anaerobic fermentation and is gaining further importance in Germany. Laboratory assays used for the determination of methane fermentation yield (MFY), i.e. the amount of methane produced per unit of dry matter, are complex and costly. Thus, the adoption of near infrared (NIR) spectroscopy, which is already successfully used for fast and cost-effective examination of animal feeds, would remedy this problem. The objectives of this study were to examine the potential of employing NIR spectroscopy to predict MFY as measured in a discontinuous fermenter, investigate the reliability of prediction of parameters related to the kinetics of MFY and compare models based on NIR spectroscopy with that on chemical composition for reliable prediction of MFY. Samples of dried whole plant material from 55 maize genotypes, grown in six environments, were analysed for their MFY using a discontinuous fermentation assay for different fermentation times. Further, chemical composition of the samples was analysed and NIR spectra were measured. Calibration models were developed to predict MFY and related traits based on NIR spectroscopy or chemical composition. Prediction of MFY after a short fermentation time (R2 = 0.88 after five days) was better than after complete fermentation (R2 = 0.77 after 35 days). Chemical composition models were always inferior to NIR spectroscopy models and showed a strong decrease in performance to predict MFY with ongoing fermentation time. The superiority of NIR spectroscopy is most likely attributable to higher information content in the NIR spectra. The fast determination of MFY by NIR spectroscopy will enable the examination of a larger number of samples and, therefore, allow for the use of MFY in maize breeding for biogas production. © IM Publications LLP 2011 All rights reserved.

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