Jane Stewart

Jane Stewart

Principal Investigator

Associate Professor
Laboratory Supervisor

Research Staff

Jorge Caballero

Dr. Jorge Ibarra Caballero

Research Associate III / Lab Manager
Jorge is a research associate at Colorado State University. He received his PhD degree in Plant Pathology at Colorado State University with research focus on transcriptomics and proteomics of Pythium iwayamai which causes snow blight of turfgrass. He also worked on the population genetics of Geosmithia morbida, a pathogen of the thousand canker disease of walnut. He is currently involved in many research projects in the Stewart Lab which deals on genomics and transcriptomics of various plant pathogens such as Rafaelea lauricola causing laurel wilt disease, Phellinus noxius causing brown root rot on tropical trees, Cytospora leucostoma causing peach canker, and Armillaria species causing root rot. He also investigates the microbial communities in potato fields in the presence of pathogens using metagenomics. Further, he collaborates with USDA Forest Service on various projects such as the development of protocol for the detection of Cronartium ribicola causing white pine blister rust through loop-mediated isothermal amplification.

Olga Kozhar

Dr. Olga Kozhar
Olga is a postdoctoral fellow at Colorado State University. She received her PhD degree in Plant Pathology at Washington State University in 2019 where she studied ecology and population biology of Botrytis cinerea, causal agent of gray mold disease, on small fruit hosts in the US Pacific Northwest. Olga’s main research interests are fungal evolution, population biology, migration and adaptation of fungal plant pathogens to hosts and environments. In 2020 Olga joined the Stewart Lab where she is studying evolution of emerging fungal tree pathogen, a newly identified potential hybrid of two fungal species – white pine blister rust (Cronartium ribicola) and comandra blister rust (Cronartium comandrae). Her another research focus lays into the investigation of population genomics of the fungus Phellinux noxius that causes brown root rot on tropical trees.

Graduate Students

John Dobbs

John Dobbs

PhD Candidate
John is a PhD. candidate at Colorado State University. He received his bachelor’s degree in Botany with a minor in Zoology and Aquaponics Design from the University of Hawaiʻi at Mānoa. He completed his M.Sc. at CSU in 2019 on the genomic analysis and development of molecular markers for identification of highly virulent strains of the koa wilt fungus, Fusarium oxysporum f. sp. koae. He advanced to candidacy in Spring 2021. His current research is on Fusarium functional pathogenomics of conifer seedling pathogenic Fusarium spp. identifying the diversity and shared evolutionary history of species found in conifer nurseries across the contiguous United States. His research highlights his skills in molecular characterization, phylogenetic analysis, population analyses, bioinformatics, primer design, whole genome analyses, metabolomics, transcriptomics, and virulence assays of filamentous fungi that cause disease on tree hosts.

Ashley Miller

Ashley Miller

PhD Student
Ashley Miller is a PhD student studying physiological and genomic responses of high-elevation pine trees to the fungal pathogen that causes white pine blister rust, and how the pathosystem may be affected by climate change. Ashley obtained a B.Sc in Botany at Oregon State University, an M.Sc with a focus in tree ecophysiology in boreal environments from the University of Freiburg, Germany, and a Master of Forestry from the University of Alberta, Canada.

Ada Fitz Axen

Ada Fitz Axen

MS Student
Ada Fitz Axen is an M.S. student studying how the microbial communities associated with different species of the fungal root pathogen Armillaria influence pathogen virulence, and how these microbial communities are affected by wildfires. Ada obtained a B.S. in Plant Science from the University of Minnesota, Twin Cities. Ada is from Minneapolis and enjoys knitting, cooking, and cross country skiing.

Noa Lindeman

Noah Lindeman

MS Student
Noah  is studying the root pathogen Onnia tomentosa. Noah is working on developing a LAMP assay for this pathogen. This LAMP assay is a diagnostic tool that can be used in the field for identifying Onnia tomentosa. He is also investigating if Onnia tomentosa is not one species but a species complex. In his free time, Noah enjoys reading, hiking with friends and foraging. He is originally from the Californian coast, and is looking forward to learning the edible plants and fungi of Colorado.

Sal Greenberger

Sal Greenberger

MS Student
Sal is currently working in the Stewart Lab as a Lab Assistant and will be starting her M.S. in January 2023. Her research will focus on assessing the role of canopy sprays in preventing fungal diseases of fruit trees, with a particular focus on Cytospora and peach trees.  As an undergrad at Oberlin College, Sal studied Visual Art and Botany. More recently, Saldiscovered an interest in microbiology and participated in a collaborative project between CU Boulder and Front Range Community College, looking for the production of antibiotic compounds by novel soil bacteria. Sal was raised in Southern California and found her way to Colorado eight years ago. After working in small-scale agriculture and as an elementary educator for several years, she is excited to be returning to school to pursue a career in Plant Pathology.

Undergraduate Students

CSU ram head.

Grace Ganter

Undergraduate Researcher
Grace is a senior from Albuquerque, New Mexico, studying agricultural biology and plant pathology. She is currently involved with the Cytospora Canker research project in Western Colorado and is interested in pursuing fungal genetics and forestry in grad school.

Gabbie Espinosa

Gabbie Espinosa

Hello! I’m and undergraduate here at CSU. I am studying Human Development and Family Studies, but I love working in the Stewart lab!

Former Lab Members

Sean Toporek

Post Doc
Currently Assistant Professor at South Dakota State University

Bradley Lalande

Major Advisor 2019 – 2022, BSPM, CSU, Ph.D.
Currently Forest Path, USDA Forest Service

Sean Wright

Major Advisor 2019 – 2022 BSPM, CSU, M.S.
Currently Forest Path, USDA Forest Service

Jonathan Bertram

Major Advisor 2019-2022 GDPE, CSU, M.S.
Currently Research Associate, CSU

Jessa Ata

Major Advisor 2017 – 2022, BSPM, CSU, Ph.D.
Currently Assistant Professor, Los BanosPhilippines

Stephan Miller

Major Advisor 2017 – 2021, BSPM, CSU, Ph.D.
Currently currently works at EPA

David Atkins

Co-Major Advisor 2018 – 2021, Forestry, CSU, M.S.
Currently PhD student at UWY

John Dobbs

Major Advisor 2017 – 2019, BSPM, CSU, M.S.
Currently Ph.D. student at CSU

Rachael Stoudt

Major Advisor 2017 – 2018, 4+1 program M.S., CSU

Kaitlin Leddy

Major Advisor, 2016 – 2018 Cell Molecular Biology, CSU, M.S.

Rachael Sitz

Co-Major Advisor/Post Doc Advisor 2015 – 2019 BSPM, CSU, Ph.D.
Currently works at Davey