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Phil Westra, Ph.D., Professor

Research interests:

  • Biology, ecology, and control of jointed goatgrass in winter wheat
  • Research on herbicide resistant weeds
  • Precision agriculture weed research
  • Herbicide/soil interactions
  • Gene flow in winter wheat
  • Weed shifts in diverse weed management systems
  • Perennial and noxious weed control

Scott Nissen, Ph.D., Professor

My responsibilities include research, applied and basic, outreach, Cooperative Extension, and some teaching. When I first came to CSU in 1995 my focus was integrated weed management in row crops. I concentrated on crops like onion, sugar beet, dry bean and potato. This applied research has been supported by the various commodity groups; however, agriculture along the Colorado’s Front Range is being displaced by an increasing population. Many communities are trying to preserve the quality of life in Colorado by purchasing farmland to establish open space and natural areas. These areas are highly disturbed and susceptible to invasion by numerous weed species; therefore, over the past three years I have been involved in more research dealing with invasive species management and adaptive strategies to establish desirable plant communities. The goal of this research is to establish sustainable plant communities that can resist re-invasion. Herbicides are an important management tool, so we also focus on herbicide fate in the environment and non-target impacts.

Todd Gaines, Ph.D., Associate Professor

My research goal is to support sustainable weed management that helps contribute to sustainable cropping systems.  To that end, I am interested in research to identify the molecular and genetic basis of complex herbicide resistance mechanisms; utilizing next-generation sequencing to study complex traits in weeds; and developing molecular markers for rapid resistance diagnostics.  Research projects in my lab study changes in evolutionary trajectories of weedy species due to human management, specifically herbicides and herbicide resistance evolution, and develop genomics and bioinformatics resources to study herbicide resistance traits in weedy species and crops.

Franck E. Dayan, Ph.D., Professor

I joined the faculty of Agricultural Biology in January 2016 after a 20-year career as a research plant physiologist for the USDA-ARS. I am interested in functional weed genomics and my research program encompasses applied projects on herbicide mode of action and evolution of resistance in weeds to more basic projects aiming to use genomic approaches to decipher traits imparting weediness: competition, cold and heat stress tolerance etc. My expertise in plant biochemistry and physiology, as well as chemical ecology complements the efforts already in place in other groups at Colorado State University.

Shannon Clark, Ph.D., Postdoctoral Researcher, Scott Nissen

I completed my Master’s of Agriculture in Integrated Resource Management at CSU in 2011. After graduating I went to work for a non-profit ranch in Estes Park, CO overseeing the conservation and weed management of their properties. In 2019, I received my Ph.D. in Weed Science from CSU working under Dr. Scott Nissen. In my current post doc position, my research focuses on evaluating herbicides for invasive species management in natural areas and rangeland and the subsequent restoration of ecosystem processes. My research also involves assessing new herbicides for industrial vegetation management and selective right-of-way weed control.

Eric Westra, Ph.D., Postdoctoral Researcher, Todd Gaines

Eric completed his Ph.D. in 2015 in Weed Science at CSU. Eric leads integrated weed management research including work on the CoAXium wheat production system, harvest weed seed control, and remote sensing/imaging for precision weed detection.

Hudson Takano, Ph.D., Postdoctoral Researcher, Franck Dayan

My research focuses on understanding herbicide mechanisms of action and resistance in plants of interest. During my Ph.D., we dissected the mechanism of action of glufosinate and provided a biochemical approach to improve its herbicidal activity. As a postdoctoral researcher at CSU’s weed research group, my role is to investigate the various aspects related to herbicide-plant interactions in order to provide better weed management tools. I also work on a project aiming to understand the physiological, biochemical and molecular basis for cold tolerance in kochia (Bassia scoparia). In the lab, I help to train and support graduate and undergraduate students with their current experiments and projects. Outside of work, I like to spend my time with family, friends and outdoor activities.

Sarah Morran: Project Manager, Todd Gaines

Sarah completed graduate school at the University of Adelaide, South Australia, in abiotic stress response in wheat. She has worked as a research scientist in weed science at the University of Adelaide and the University of California – Davis, before joining the Weed Research Lab in 2019. She is the project manager for the International Weed Genomics Consortium and conducts research on the evolution of herbicide resistance in polyploids.

Marcelo Rodrigues Alves de Figueiredo: Ph.D. Student, Todd Gaines

I received my B.S. in Agricultural Engineering from the University of São Paulo at the “Luiz de Queiroz” College of Agriculture, Brazil in 2012. As an undergraduate, I worked on applied field research in weed science. In 2015 I completed a M.S. in Crop Science at the same College, focusing on herbicide chemistry, physiology and biochemistry in weeds and model plant species. My current Ph.D. research is focused on weed genetics and molecular biology. Specifically, I am studying the complex issue of weed resistance to auxinic herbicides. My main objective is to integrate related genetic, biochemical, physiological and agronomic knowledge of these resistant species in order to provide effective weed management plans for agricultural production systems.

Neeta Soni: Ph.D. Student, Todd Gaines

I am originally from Costa Rica. I received my B.S. in Agronomy in 2009 from EARTH University, Costa Rica.  I worked as a research assistant in the same institution. Later on I worked for ECOM agroindustrial group in Costa Rica doing extension work with coffee farmers to improve their agriculture practices.  In 2014, I received my M.S. in Agronomy with a minor in Soil and Water Sciences from the University of Florida. My research was looking for the effects of vinasse and biochar (byproducts of bioenergy production) on weed germination, growth and control. In summer 2015, I joined the Bioagricultural Sciences and Pest Management department for my Ph.D. program in Weed Science under the advisory of Dr. Todd Gaines.  I am interested in and weed biology and molecular genetics to address herbicide resistance issues. Currently my research is focused on herbicide resistance traits in sunflower. In addition, I am working on a seed retention study of winter annual grass weeds at wheat harvest on Eastern Colorado. At the same time I am collecting samples of annual grass weed species for an herbicide resistance survey.

Raven Bough: Graduate Student, Franck Dayan

Despite being raised with minimal plant interactions, I fell in love with plants and chose to pursue a B.S. in horticulture at the University of Arkansas in Fayetteville, AR. After spending my childhood and college years in the same hometown, it was time for a change of scenery. I relocated to Colorado in 2013 to carry out an M.S. in CSU’s renowned potato breeding program, located in the San Luis Valley. The opportunity to work with gas chromatography-mass spectrometry for potato flavor profiling shifted my interest in plant breeding to applied plant chemistry and metabolism. During fall of 2016, I began a corresponding Ph.D. program with Franck Dayan. Currently, I am investigating quizalofop herbicide resistance in wheat. I spend time beyond graduate school responsibilities reading/watching sci fi, playing board games, meddling in the yard, and taking my dogs on outdoor adventures.

Abby Barker: Graduate Student, Franck Dayan

I graduated with my B.S. in biochemistry, with minors in mathematics and chemistry, from Colorado State University in 2016. My undergraduate research under Todd Gaines led me to an interest in agricultural sciences and more specifically herbicide resistance in weeds. In the fall of 2016 I began my Ph.D. under Franck Dayan. My project focuses on elucidating the mechanism of PPO-inhibiting herbicides as well as precise mechanisms of resistance in multiple species, including Amaranthus tuberculatus. I am interested in the biochemistry of herbicide resistance, as well as the fate of herbicides in resistant plants and crops. In 2018 I was selected to be one of the inaugural FFAR Fellows. When not in the lab I train for triathlons as well as mountain biking and hiking.

Olivia Todd: Ph.D. Student, Todd Gaines

Originally from Loveland, CO I came to CSU in 2012. In 2016, I graduated from Colorado State University and the University honor program with a B.S. in Soil and Crop Science with a specialization in plant biotechnology, genetics and breeding. After completing my senior honor thesis with Todd in 2016, I have decided to pursue a Ph.D. with Todd and focus my energy on investigating fluroxypyr resistance in kochia scoparia using RNA-sequencing. I also am working with the United Sorghum Checkoff Program to develop herbicide tolerance traits in the cereal grain, sorghum. When I’m not working on my research, I am outside with my dog or in the climbing gym.

Carlos Alberto Gonsiorkiewicz Rigon: Ph.D. Student, Todd Gaines

I’m originally from Brazil. I received my B.S. in Agronomy from Federal University of Santa Maria, Frederico Westphalen, RS, Brazil in 2016. In this period, I began to work on Weed Science, focused on allelopathy and weed competition. For one and a half years I studied at Hochschule Neubrandenburg of Applied Science, Neubrandenburg/Germany. During this period, I did an internship at Max Planck Institute of Molecular Plant Physiology, Potsdam/Germany, where my passion on molecular biology began. On May 2019, I completed a M.S. in Crop Science from Federal University of Rio Grande do Sul, Porto Alegre, Brazil. My master project focused on resistance evolution of Echinochloa crus-galli trough recurrent selection with herbicide safener and herbicide mixture. In Fall 2019, I joined the AgBio department for my Ph.D. program in Weed Science. My research at CSU is focused on understanding the genetic regulation of cytochrome P450 genes in resistant weeds metabolism based. Previously studies in our Lab found candidate P450 genes in HPPD-resistant Amaranthus palmeri. My focus is to understand why these genes are being upregulating in the resistant biotype. As a side project, I’m working with the selected biotypes of Echinochloa crus-galli from my master project.  In my free times, I like cycling, spend time with my wife and friends, and as a Brazilian, I like to play soccer.

Mirella Farinelli Ortiz: Graduate Student, Franck Dayan

I am originally from Brazil and came to Colorado in January 2015 as part of my undergraduate studies. I worked as an undergrad intern in Dr Nissen’s lab for a year and half, when I received my B.S. degree in Agronomy and he recruited me as a M.S. student. My M.S. project was focused in endothall behavior in aquatic weeds. Currently I am a Ph.D. student under Dr. Franck Dayan, continuing to work with aquatic weeds and their management. My focus now is to elucidate how florpyrauxifen-benzyl, a new active ingredient for aquatic weed management and weed management in rice production, behaves in aquatic and terrestrial plants and its fate in planta and under different environmental conditions. I’m also studying the ester formulation of 2,4-D and its behavior in the aquatic environment.

Rachel Seedorf: Graduate student, Scott Nissen

As a Colorado native, I grew up in eastern Colorado in the small town of Yuma. Growing up on a corn and wheat farm, my interest for agriculture started at a young age. My B.S. degree was completed here at CSU in Soil and Crop Sciences with a minor in Ag Business. After taking a weed management class under Dr. Nissen, I decided to turn my focus on weed management in natural systems and am currently completing my Master’s Degree in Weed Science under Dr. Scott Nissen. My project is focused on working with the environment sustainability department at the Denver International Airport to help develop a weed management plan for the many acres they own. The goal of this project is to create a long-term, sustainable plan the land managers can use to successfully maintain and restore desirable plant species. In addition, I am working on a few projects looking at cheatgrass control using indaziflam in burned vs. non-burned areas across the Front Range using indaziflam.

Kristen Tanz: Graduate Student, Scott Nissen

I’m a Masters student studying Weed Science in Dr. Scott Nissen’s lab, with a focus on evaluating herbicide combinations and controlling aquatic and riparian weeds. I received my B.S. in Biology from the University of North Texas in 2007. I had the opportunity to serve as a Peace Corps volunteer in Zambia from 2010-2012, with projects centered on sustainable agriculture and forestry. From 2013-2017, I worked with the Texas Department of Agriculture in a regulatory and training role. Outside of work, I’m interested in climbing, cooking, & science fiction.

Andrew Effertz: Graduate Student, Phil Westra

Growing up in rural North Dakota and being surrounded by farming has developed my interest in agriculture. I obtained my B.S. in Crop and Weed Science from North Dakota State University in 2018 and moved to Colorado shortly there after to begin my M.S. in Weed Science at CSU with Dr. Phil Westra. My project focuses on physiological aspects, resistance mechanisms, and control methods for Amaranthus palmeri  and Bassia scoparia. We hope to obtain a better understanding of the competitive advantages and survival abilities these two weeds have over other common cropland weeds, further study their resistance mechanisms, and develop effective control methods for susceptible and resistant biotypes. In my free time, I enjoy golfing, attending sporting events, and keeping close tabs on NDSU athletics.

Crystal Sparks: Ph.D. Student, Todd Gaines

Majoring in Soil and Crop Science, with a concentration in plant genetics, breeding, and biotechnology, Spring 2016 is my first semester as a student at Colorado State University. I am transferring in as a junior after recently completing an associate of science degree at AIMS Community College. A few months prior I joined the Gaines lab, where I have begun to learn molecular techniques and skills that will support my research interest and career goals. While assisting with several of the lab’s current projects I have been exposed to concepts such as gene copy number variation, molecular cloning, herbicide resistance mechanisms, plant metabolism and physiology, and more. I feel immensely grateful for the opportunity to gain this knowledge and experience.
Some of my future research interests and topics of concern include: Investigating issues faced by growers, at a molecular and genetic level. Utilizing traditional plant breeding alongside biotechnology to develop useful and economical cultivars of crop or medicinal plants. Seeking solutions to malnutrition amid a growing population and disputed climates. Minimizing impacts of crop production on surrounding ecosystems and public health.

Past Students

Eric Patterson: Graduated Spring 2018

I received a double B.S. in Zoology/Biology in 2009, a M.S. in Botany in 2013, and Ph.D. in Bioagricultural Science with a specialization in Weed Science in 2018 from Colorado State University. I wrote my dissertation on the genetics and genomics of herbicide resistant Kochia scoparia, specifically focusing on the genetic underpinnings of copy number variation and gene duplication as it relates to glyphosate resistance. My general research interests are weed genomics and understanding genome plasticity in the face of abiotic stress and herbicides. After receiving my Ph.D. I was awarded research fellowship to study the genome of Blackgrass in a three-way collaboration with Bayer International, Rothamsted Research and Clemson University as a post-doctoral researcher.

Anita Küpper, Ph.D. Graduated Spring 2018

Anita grew up in Germany, where she received her B.S. in Environmental Impact Assessment and went on to earn her M.S. in Environmental Chemistry and Health from the University of Copenhagen, Denmark. She wrote her master thesis in aquatic toxicology at the University of California – Riverside. In June of 2014 Anita joined the Weed Science group at the Colorado State University under the guidance of Dr. Todd Gaines. Her various projects focused on the mechanism of metabolic resistance to tembotrione and the origin of glyphosate resistance in Palmer amaranth as well as 2,4-D resistance in Indian hedge mustard.  She now works with Dr. Roland Beffa at the Weed Resistance Competence Center of Bayer CropScience in Frankfurt, Germany.

Derek Sebastian: Graduated Spring 2017

Derek Sebastian completed his M.S. at CSU in 2014 and was co-advised by Drs. Phil Westra and Scott Nissen. He continued on to finish his Ph.D. in 2017 under the guidance of Dr. Scott Nissen and is now a member of the Bayer VM Stewardship and Development Team where he continues to develop indaziflam in the western U.S.

Christopher Van Horn, Ph.D., Graduated Summer 2016

After graduating with his Ph.D. under the advisement of Dr. Phil Westra, Christopher took a post-doc position with the USDA-ARS under Dr. Jianchi Chen doing genomic sequence analysis of Xyllella fastidiosa bacterial strains causing Pierce’s disease in grapevine. He now lives with his wife and two children in the San Joaquin Valley, CA.

Dean Pettinga: Graduated Fall 2016

I’m a graduate of Calvin College in my hometown of Grand Rapids, Michigan.  I received my degree in biology with a minor in biochemistry. Food security is one of the greatest problems facing the world in this century. This problem does not have any individual solution. I see problems and opportunities for improvement in everything from personal eating habits to natural resource management and technology. Due to my interests in basic biology, I hope to approach this problem from a scientific perspective. The opportunity to work in a lab with these facilities and interests, solving problems directly relevant to farmers drew me to the Gaines Lab. When I’m not in the lab, I like to spend my time on a hike, run, bike ride, a day skiing in the mountains, or anything else that gets me outdoors.

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