Current Personnel


Pam Ronald
Pamela Ronald
I am a professor in the Dept of Plant Pathology and the Genome Center at UC Davis. I have a PhD in Molecular and Physiological Plant Biology from UC Berkeley and was a postdoc at Cornell. I got interested in plant microbe interactions while studying biology at Reed College and later moved to Sweden to study mycorrhizal fungi. I enjoyed living in Sweden/France for three years but am glad to be back in California, where I grew up. When not doing science, I love to spend time hiking in the Sierra Nevada mountains with my friends, family and our dog.
Valley Stewart
I am a Professor Emeritus of Microbiology whose research career focused on studying the physiology and genetics of enterobacteria. I have been collaborating with Prof. Ronald since 2016, focusing on Xanthomonas oryzae pv. oryzae.

Visiting Faculty

Felipe Ricachenevsky
I am a professor from the Federal University of Rio Grande do Sul in Brazil. My group focus is plant nutrition and ionomics, and the genetics that controls it. Our goal is to enhance the nutrient content of staple grains like rice, and to gain a deeper understanding of the processes that govern the uptake and distribution of nutrients within plants. This will aid in making fertilizer usage more sustainable and cost-effective. During my time at the laboratory, I plan to utilize Kitbase as a tool for both forward and reverse genetic screening. In addition to being a scientist, I am also passionate about teaching. In my free time, I love spending as much time as possible with my daughter and wife, especially if we go on trips; reading books, running, and playing music.


Randy Ruan
I am Professor Ronald’s Lab Manager. I graduated in Yangzhou University in China with a Master and Bachelor in Agronomy and Plant Genetics. I moved to United States in 1994 and joined Ronald lab in Dec 1994. I enjoy working with Pam and the hardworking lab group. Besides working on research and manage Ronald lab I spend most my spare time on gardening. Karen and I have a son Colin and two cats, Big Guy and Calypso.
Malena B. Teeters
I am Professor Ronald's Program, Educational, and Outreach Assistant. Among my duties are managing Professor Ronald's calendar, arranging meetings, making travel arrangements, and assist in proofing documents. I obtained a bachelor's degree in Accounting from the “Instituto Tecnologico Autonomo de Mexico” and in 2021 I obtained a Master's in Organizational Leadership from California Baptist University. I moved to the United States in 1987 and I joined UC Davis in March of 1988. I have had the privilege of serving as a Chief Administrative Officer for a research center, and I am also an experienced Contratcts and Grants Analyst and a Financial Analyst. I am proud to work for UC Davis, I witnessed amazing growth in the last 35 years. I am married to David and we have two adult children Jesse and Sara. In our free time, we love to spend time with our family and friends, spend time with our four dogs, play pickleball, and to travel.

Specialist / Bioinformatician

Rashmi Jain
I am an Associate Specialist at UC Davis from New Delhi, India. While doing my undergraduate course in Biology I also joined the diploma in computer science, Burned by the desire to dig into computational programming and use my background in biology, I earned the Master's degree in Bioinformatics from Sikkim Manipal University. I always believe in exploring the world and am ready to take on new challenges, so in the year, 2013, I came across an opportunity to work in Pamela Ronald's Lab, at the University of California, Davis. Other than that, I like to watch TV and travel.

Assistant Project Scientist

Maria Florencia Ercoli
I am originally from Argentina; I have a Ph.D. in Biological Sciences and a BSc in Biotechnology from the National University of Rosario. During my Ph.D. I studied regulatory networks controlling Arabidopsis root development and discovered my passion for plant genetics and molecular biology. I decided to apply this expertise to a different plant model, a crop, so in 2018 I joined the Laboratory of Prof. Pamela Ronald as a Postdoctoral Scholar. I am currently working as part of a team that, using different approaches, aims to elucidate the molecular mechanisms underlying the ability of small peptides to control plant development and plant-microbe interactions. My passion is to see life through a microscope; therefore, I approached this key research question from a cellular biology perspective, studying the anatomical modifications these hormones are causing in detail. If you want to see fun pictures from our research, you can find me on Twitter (@NeCesiTo1TiemP0).
In my free time, I love spending time with my husband Jean and our dog Gino; we go for hikes, camping, and bike rides. I also love cooking, watercolor painting, and gardening.

Postdoctoral Scholars

Artur Teixeira de Araujo Junior
I am a postdoc in Ronald Laboratory (Department of Plant Pathology – UC Davis). I have a PhD in Cellular and Molecular Biology from the Federal University of Rio Grande do Sul (Brazil) and a masters in Biotechnology from the Federal University of Pelotas (Brazil). I also had the experience of being a Rural Producer and Property manager in a farm for 6 years. This helped me to understand the vision of two very different points of work: developer of new technology and producer/user of these final products. I am responsible for the collection of rice mutants (KitBase) and sorghum mutants. My projects involve bioinformatics, laboratory and greenhouse work. I'm glad to study and learn about the modifications in the DNA and how these mutations can help the society with plants more tolerant to stress, more productive and with greater nutritional value in grains. In my free time, I like to improve my creative side and to do physical activities (hiking, climbing, among others).
Dee Dee Luu
I joined the Ronald lab as a graduate student, graduated with a Ph.D. in Microbiology, and now work as a postdoc. I earned my B.S. at UC Irvine studying poliovirus translation initiation. I then moved on to studying baculoviruses at Cal State Long Beach before I settled at UC Davis. My current research examines the virulence effects of a bacterial peptide that mimics the plant host. In my spare time, I enjoy DIY projects and creating art.
Alyx Shigenaga
I joined the Ronald Lab as a Postdoctoral Researcher in August 2021. I have a PhD in Plant Pathology from Colorado State University and a BSc in Microbiology and Botany from Humboldt State University. During my PhD, I studied the role the plant hormone cytokinin plays in heat-induced disease susceptibility of plants to bacterial pathogens. To learn more about my PhD research, you can see my 3-minute lightning talk here. My current research in the Ronald Lab focuses on further understanding the biological role sulfated plant peptide hormones play in plant-microbe interactions and identifying/characterizing the PSY receptor using various plant systems. Besides doing science, I enjoy spending time with my husband and dog outdoors hiking, kayaking, or swimming. You can follow me on Google Scholar.
Ellen Rim
I am a Life Sciences Research Foundation postdoctoral scholar studying rice immune receptor signaling with the goal of developing crops with greater pathogen resistance. I studied animal systems throughout my undergraduate years at Harvard College and PhD studies at Stanford University focusing on cell signaling in mammalian stem cells. Towards the end of graduate school, I became interested in plants and the role of plant sciences in addressing climate change and food security. In the Ronald Lab, I'm learning a lot about crops and engineering plant immune receptors to expand their pathogen recognition ability. Outside of lab, I enjoy cycling and playing ultimate frisbee.
Peter Lynagh
I went to college hoping to learn about Kenyan coffee, which I love. I earned an agricultural B.S. from University of Maryland where I assisted in researching soils, greenhouse gases and insects. More recently, my UC Davis Plant Biology Ph.D. research improved detection and characterization of genome edits in plants. I developed a plant PCR method that is faster, less expensive, easier, uses less plastic and chemicals, and causes minimal tissue damage. My first postdoctoral position is here in the Ronald Lab. I am analyzing rice root system architectures, and related aspects, for improving carbon sequestration in soil.
Jin CY Liao
I received my PhD in Plant Biology from Iowa State University. My PhD works were trying to understand the complicated molecular mechanisms by which plants regulate in response to dynamic environmental conditions. I particularly focused on the interplay between autophagy and phytohormone brassinosteroid signaling in Arabidopsis. I am currently working on the regulation of plant peptide hormones and their receptors in the Ronald Lab. Besides research, I am also passionate about travel and science communication. I have my own website Jin's LifeRχiv (, and most of my posts are about plant biology. I create funny and cute illustrations/comics that explain the latest plant science research in a way everyone can understand.

Visiting Researchers

Kashaf Zafar
I have joined Ronald's Lab as a visiting scholar. I am passionate about learning new things and found it very interesting to gain experience from here. Currently, I am working on understanding the role of plant peptide hormones on root development in rice. I have done PhD in Agricultural Biotechnology from National Institute for Biotechnology and Genetic Engineering, Pakistan. My PhD work was on Establishment of genome engineering for herbicide and bacterial blight resistance in Basmati rice using CRISPR/Cas9. I have mutated the promoter region of SWEET14 gene using non homologous end joining (NHEJ) to develop resistance against bacterial blight. To develop herbicide tolerance, the Acetolactate synthase gene of basmati rice was targeted using homology directed repair (HDR). I have also worked on CRISPR based directed evolution as a visiting researcher at King Abdullah University of science and technology, Saudi Arabia. Other than science related things, I love to spend time with my family, and I also enjoy cooking.

Junior Specialist

Ryan Packer
I graduated from the University of California, Davis with a bachelor's degree in entomology. I entered college with a strong passion for working with vector-borne diseases. While working in the Ullman Lab, I found a passion for plants and molecular biology. I hope to keep pursue a career in researching the intricate interaction between vector, pathogen, and plant host. Other than science…. I love to bike, garden, and go to the movies.

Undergraduate Assistants

Kaley Ng
I am a Biological Systems Engineering undergraduate at UC Davis. I joined the Ronald Laboratory last Spring as an undergraduate researcher, where I am working with Ellen and Alyx. During my free time, I enjoy hiking and trying new recipes.
Rafael Vasquez-Chan
I am an undergraduate student here at UC Davis pursuing a degree in biotechnology with a focus on plants. I joined the Ronald lab to work with Peter in improving carbon sequestration by rice. I like to spend my free time playing video games, being in nature, and doing dragon boat with UC Davis team.
Nguyen Ho
I'm a Computer Science undergraduate student at UC Davis. I joined Ronald laboratory to help with data computation & analysis and managing websites. In my spare time, I like to play and watch soccer. My favorite team is Manchester United (UK).