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My curriculum vitae

2007-09-24T16:07:00.000-07:00

AUDREY DARRIGUES

229 Williams Hall – The Ohio State University – Wooster, OHIO 44691

EDUCATION

PhD (2007) in Horticulture and Crop Science, The Ohio State University, Wooster, Ohio
Major/Professor: Plant Breeding and Genetics / David M. Francis

Master of Science (2003) in Agronomy, Iowa State University, Ames, Iowa
Major/Professors: Plant Breeding / M. Paul Scott and Kendall R. Lamkey

Bachelor of Science (2001) in Liberal Arts and Science, Iowa State University, Ames, Iowa
Major/Minor: Biology / Agronomy

WORK EXPERIENCE

Graduate Research Assistant
September 2003 to 2007
The Ohio State University, Department of Horticulture and Crop Science, Wooster, OH, Dr. David Francis, Advisor
PhD’s dissertation involving the application of molecular tools in a tomato breeding and genetics program aimed at understanding and elucidating the genetics of color and color uniformity. Implementation of novel software for digital phenotyping of tomato color disorder. Marker-trait association via SNP mapping.

Graduate Research Assistant
May 2001 – August 2003
Iowa State University, Department of Agronomy, Ames, IA, Dr. M. Paul Scott, Advisor.
Master’s thesis involving the planning and organization of field work as required in breeding nurseries, collecting data and preparing samples for analysis. Learning and applying analytical methods for quantifying and determining protein quality. Compiling data for over 1,000 samples and using statistical tools for data analysis.

Instructor
Fall 2002
Iowa State University, Department of Agronomy, Ames, IA.
Given full responsibilities to teach an undergraduate course, junior-senior level, in Crop Physiology, the interrelationship between structure and function (Agron230).

Teaching Assistant
Spring 2002
Iowa State University, Department of Agronomy, Ames, IA.
Assisted Dr. Ricardo Salvador in teaching Crop Physiology, Agron230. Graded quizzes and homework assignments and lectured class on five occasions during the semester. Provided help to students with questions and problems related to the class.

Independent Study
Fall 2000
Iowa State University, Department of Agronomy, Ames, IA, Dr. Arden Campbell and Christian Buffard, Advisors.
Conducted a field experiment in screening new events for resistance to the European corn borer. Inoculated, tested the efficacy of the transgene, and collected, analyzed and submitted data in useable form.

Corn Research Associate
October 1996- May 2001
Pau Seeds Inc., Boone, IA, under the supervision of Christian Buffard, Director
In conjunction with undergraduate studies, worked on a part-time basis in a corn research station. Involved in planting, maintenance of nurseries, summer pollination and detasseling, data collection, harvesting, shelling and storage of seed. Gained responsibilities in setting-up nurseries and isolated crossing nurseries of about 10,000 crosses for planting, in managing summer and harvest crews, in organizing laboratory duties, and in managing and organizing research seed inventory.

PUBLICATIONS
Darrigues, A., M.D. Robbins, W. Yang, and D.M. Francis. 200#. Dissecting variation in tomato fruit color quality through digital phenotyping. Plant Breeding. In preparation.

Darrigues, A., J. Hall, N. Dujmovic, S. Gray, E. van der Knaap, and D.M. Francis. 200#. Tomato Analyzer – Color Test: a new tool for efficient digital phenotyping. J. Am. Soc. Hort. Sci. Submitted.

Darrigues, A., S. Schwartz and D.M. Francis. 200#. Optimizing sampling of tomato fruit for carotenoid content with application to assessing the impact of ripening disorders. J. Agric. Food Sci. In revision.

Darrigues, A., A. Clivati-McIntyre, S. Schwartz and D.M. Francis. 2007. Increasing the Carotenoid Content of Tomato by Managing Variety Choice and Soil Fertility for Color and Color Uniformity. Acta Horticulturae 744:323-328.

Darrigues, A., K.R. Lamkey, M.P. Scott. 2006. Breeding for grain amino acid composition in maize IN Plant breeding : the Arnel R. Hallauer International Symposium (2003: Mexico City, Mexico), edited by K. R. Lamkey and M. Lee, chapter 24. Ames, Iowa: Blackwell Publishers.

Darrigues, A., C. Buffard, K.R. Lamkey, M.P. Scott. 2006. Variability and genetic effects for tryptophan and methionine in commercial maize germplasm. Maydica. 50:147-156

PRESENTATIONS AND PROFESSIONAL ASSOCIATIONS

2007 XV Plant and Animal Genome Conference, San Diego, California, 13-17 January 2007, poster presentation (Darrigues, A, J Hall, N Dujmovic, S Gray, E van der Knaap, D M. Francis, Dissecting Variation in Tomato Fruit Color Quality through Digital Phenotyping and SNP Mapping).

2006 Horticulture and Crop Science Graduate Research Retreat, OSU, Columbus, Ohio, 13-14 October 2006, poster presentation (Darrigues, A, W Yang, and D M Francis, DNA Microarray-Based Discovery of Molecular Markers for the Improvement of Tomato Color and Nutritional Quality); 1st place award for poster competition.

2006 Plant Molecular Biology & Biotechnology, OSU/OARDC, Wooster, Ohio, 31 March-1 April 2006, invited speaker (Darrigues, A, W Yang, and D M Francis, DNA-Microarray Discovery of Molecular Markers for the Improvement of Tomato Color and Nutritional Quality).

2005 XV Meeting of the Eucarpia Tomato Working Group, Bari, Italy, 27-30 September 2005, invited speaker (Darrigues, A, W Yang, and D M Francis, DNA-microarray Detection of Molecular Markers for Improving Color and Nutritional Quality in Tomato).

2005 International Symposium on Human Health Effects of Fruit and Vegetable, Quebec, Canada, 17-20 August 2005, invited speaker (Darrigues, A, A Clivati-McIntyre, S Schwartz and D M Francis, Increasing the Carotenoid Content of Tomato by Managing Variety Choice and Soil Fertility for Color and Color Uniformity).

2003 Arnel Hallauel International Symposium on Plant Breeding, Mexico City, Mexico, 17-22 August 2003, poster presentation (Darrigues, A, K R Lamkey and M P Scott, Nutritional Improvement for Methionine and Tryptophan Content in Maize).

2003 Maize Genetics Conference, Lake Geneva, Wisconsin, 13-16 March 2003, poster presentation (Darrigues, A., Scott, M. P., Lamkey, K. R., Recurrent Selection for Methionine and Tryptophan Content in Maize after One Cycle).

2002 Long-Term Selection Conference, University of Illinois, Urbana-Champaign, June 2002, poster presentation (Darrigues, A., Lamkey, K. R., Scott, M. P., Selection for Methionine and Tryptophan Content in Maize).

Eucarpia
Tomato Genetics Cooperative
Member of Gamma Sigma Delta (The Honor Society of Agriculture), 2003 initiate

UNIVERSITY ENGAGEMENTS & AWARDS

The Ohio State University / Ohio Agricultural Research and Development Center, Wooster, Ohio
- OARDC Research Enhancement Competitive Grant, 2005 recipient, $5000
- OARDC Research Enhancement Competitive Grant, panel review member (2006)

The Ohio State University / OARDC, Department of Horticulture and Crop Science
- Seminar Committee (2003 – 2007)
- Graduate Studies Committee, Graduate student representative (01.2006 – 09.2007)
- Graduate Research Retreat, Organizing and Judging Committee, chair (2006)
- Graduate Studies Committee Travel Grant, 2007 recipient, $500

My academic profile at ISU

2007-09-24T16:04:00.000-07:00

MS PROGRAM AT IOWA STATE UNIVERSITY
Maize Protein Quality; Paul Scott, P.I.

Publications
Darrigues, A., C. Buffard, K.R. Lamkey, M.P. Scott. 2006. Variability and genetic effects for tryptophan and methionine in commercial maize germplasm. Maydica. 50:147-156

Maize (Zea Mays L.) is a major food and feed crop, however, maize proteins are nutritionally imbalanced due to low levels of certain essential amino acids, including tryptophan and methionine. The objectives of this study were (1)to determine the variability in methionine and tryptophan levels present in commercial maize inbred lines, (2) to characterize the genetic groups of commercial maize breeding germplasm for their methionine and tryptophan content, (3) to estimate general combining ability, specific combining ability, and reciprocal genetic effects for tryptophan and methionine content in this germplasm. Seventy-six inbred lines representing nine different genetic groups were evaluated. There was significant variability among the genetic groups and among the inbreds in some of the groups. Two six-parent diallel mating designs were completed with parents selected for low or high methionine or tryptophan levels. The analysis of the diallel crosses revealed significant general and specific combining ability effects, as well as reciprocal effects. These effects were of greater magnitude in the methionine diallel than in the tryptophan diallel. These studies suggest that methionine responds better to selection than tryptophan. Maize breeders will be able to exploit these genetic effects to develop hybrids with elevated levels of tryptophan or methionine.

Darrigues, A., K.R. Lamkey, M.P. Scott. 2006. Breeding for grain amino acid composition in maize IN Plant breeding : the Arnel R. Hallauer International Symposium (2003: Mexico City, Mexico), edited by K. R. Lamkey and M. Lee, chapter 24. Ames, Iowa: Blackwell Publishers.

My academic profile at OSU

2007-09-24T15:46:00.000-07:00

PhD PROGRAM AT THE OHIO STATE UNIVERSITY
Tomato Breeding and Genetics; David Francis, P.I.

Research interests & endeavors
My research interests encompass plant breeding for quality traits and the implementation of molecular tools to improve the efficiency of trait-specific selection. My research project aims at understanding and elucidating the genetics of tomato color and color uniformity. It will be addressed by (i) verifying and applying single nucleotide polymorphism (SNP) discovered via microarray analysis, (ii) studying the genetic structure most efficient for color improvement, and (iii) understanding the effect of yellow shoulder disorder (a blotchy ripening disorder) on the nutritional quality of tomato, as defined by its carotenoid content.

Publications & Presentations
Darrigues, A., M.D. Robbins, W. Yang, and D.M. Francis. 200#. Dissecting variation in tomato fruit color quality through digital phenotyping. Plant Breeding. In preparation.

Darrigues, A., J. Hall, N. Dujmovic, S. Gray, E. van der Knaap, and D.M. Francis. 200#. Tomato Analyzer – Color Test: a new tool for efficient digital phenotyping. J. Am. Soc. Hort. Sci. Submitted.

Darrigues, A., S. Schwartz and D.M. Francis. 200#. Optimizing sampling of tomato fruit for carotenoid content with application to assessing the impact of ripening disorders. J. Agric. Food Sci. In revision.

Darrigues, A., A. Clivati-McIntyre, S. Schwartz and D.M. Francis. 2007. Increasing the carotenoid content of tomato by managing variety choice and soil fertility for color and color uniformity. Acta Horticulturae 744:323-328.

Darrigues, A, J Hall, N Dujmovic, S Gray, E van der Knaap, D M. Francis. 2007. Dissecting variation in tomato fruit color quality through digital phenotyping and SNP mapping. XV Plant and Animal Genome Conference, San Diego, California. Poster presentation.

Color is among the most important attributes of tomatoes for processing. Both color and color uniformity are affected by yellow shoulder disorder (YSD), a ripening disorder that results in discoloration of the proximal end tissues of the fruit. Cells from YSD tissue are smaller and more randomly organized, and the development of the chromoplast is altered. YSD reduces lycopene and beta-carotene concentrations by 18% and 22%, respectively. We have implemented a color measurement module in the Tomato Analyzer software to accurately measure color uniformity from scanned images of fruit. This approach improves the efficiency of collecting data, provides high correlations with data collected by colorimeter, and improves estimates of genetic contributions to color uniformity. Variance partitioning suggests that YSD incidence and severity are affected by both genetics and environment. To elucidate the genetic basis of YSD, we are developing SNPs for application in inbred backcross breeding populations. We are using both analyses of large public EST databases and hybridization to oligonucleotide arrays for SNP discovery. We have found seven putative QTL associated with chroma (color intensity), five QTL for hue (color), and four QTL for color uniformity. The presence of QTLs with positive alleles from both S. lycopersicum and S. pimpinellifolium suggests the possibility of obtaining transgressive segregants with improved color. Directional selection strategies are being used to confirm these QTL and evaluate genetic correlations to other fruit quality traits, disease resistance, and yield.

Darrigues, A, W Yang, and D M Francis. 2006. DNA-microarray discovery of molecular markers for the improvement of tomato color and nutritional quality. Plant Molecular Biology & Biotechnology, OSU/OARDC, Wooster, Ohio. Invited speaker and poster presentation.

Darrigues, A, W. Yang, and D. Francis. 2005. DNA-microarray detection of molecular markers for improving color and nutritional quality in tomato. EUCARPIA Tomato Workshop, Bari, Italy. Invited speaker.

Color is among the most important attributes of tomato for processing into whole and diced products. Both color and color uniformity are greatly affected by Yellow Shoulder Disorder (YSD), a ripening disorder that results in discoloration of the proximal end tissues of the fruit. We show that lycopene and beta-carotene concentrations are reduced by 18% and 22%, respectively, in fruits affected by YSD. Variance partitioning suggests that YSD incidence and severity is affected by both genetics and environment. In order to elucidate the genetic basis of YSD, we are developing single nucleotide polymorphisms (SNPs) as molecular markers for application in three inbred backcross populations derived from either L. esculentum x L. esculentum or L. esculentum x L. pimpinellifolium crosses. SNP discovery for application in these populations is based on both analyses of large public EST databases and on hybridization to a custom oligonucleotide array. The array was hybridized with target cDNA from L. esculentum (Ohio 7814) and L. pimpinellifolium (LA1589). We developed algorithms to detect outliers and identified 1,296 potential SNPs. These putative SNPs are being verified by sequencing, screened for utility as markers on a collection of 92 L. esculentum lines and wild relatives, and applied to the genetic dissection of YSD. Implementing SNP-based marker technology has the potential to dramatically alter our approach to genetic characterization. Results and interpretation from this study will help bridge the gap between the goals of genetic and crop improvement research by facilitating the use of population structures that favor simultaneous genetic analysis and crop improvement.

Darrigues, A, A. Clivati-McIntyre, S. Schwartz, and D. Francis. 2005. Increasing the Carotenoid content of tomato by managing variety choice and soil fertility for color and color uniformity. FAV Health: International Symposium on Human Health Effects of Fruits and Vegetables, Quebec City, Quebec. Invited speaker.

The predominant carotenoids in tomato, beta-carotene and lycopene, provide health benefits. Beta-carotene is recognized as a nutrient due to pro-vitamin A activity and lycopene consumption has been correlated with a reduction in certain cancers. Despite the potential benefits, the processing industry does not place value on carotenoid content in contract fee structures or processor grades. Color, an indirect measurement of carotenoid content, and color uniformity are valued in the grading system. The quality of tomato, as defined by its grade, can be reduced by ripening disorders such as yellow should disorder (YSD) that affect the uniformity of fruit color. We show that lycopene and beta-carotene are reduced by 18% and 22%, respectively, in fruits affected by YSD. A survey of YSD incidence in the Midwest, USA, between 2001-2003 indicated that soils with lower Phosphorous (P) and lower available Potassium (K) are more prone to YSD. Currently 23% of the tomato processing fields in this region are at a higher risk of YSD due to soil fertility. Targeted application of K by drip irrigation and adequate soil nutrition have a positive impact on both yield, fruit color, and color uniformity. YSD also has a genetic cause. Best management practices to reduce the risk of YSD combine fertility management with varieties that are more resistant to the disorder. These approaches can be used to optimize the potential for health benefits due to higher carotenoid content and may be encouraged under current contract structures.

Welcome!

2007-09-24T15:40:00.000-07:00

This blog will replace my OSU webpage as I transition into a new research program. That's right... I'm PHinisheD at OSU!!

If I manage to discover the intricacies of this blogger, you should be able to find the same information as my OSU webpage. That is...

- My academic profile
- My curriculum vitae
- My personal pages

If you have any questions, please contact me by responding to this blog!

Enjoy!

Audrey