Kerik Cox
Professor, School of Integrative Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell AgriTech
My program specializes in applied plant pathology, mycology, and bacteriology in addition to undergraduate, graduate, stakeholder, grower, and community education. The program's mission is to provide a better understanding of the relationships between life history features of plant pathogens of fruit crops and applied disease management practices. Understanding the impacts that management practices have on aspects of pathogen life history such as survival, inoculum production, community structure, and propensity for resistance development will, in turn, allow for the sustainability and refinement of such practices to better manage disease.
Resources
- Cox Program: Tree and Small Fruit Extension Resource Blog.
- Scaffolds Podcast on Apple Podcasts and Spotify.
- YouTube channel.
Interests
Fruit pathology
Antimicrobial resistance and disease forecasting
Biological control and germicidal light
Recent Research
My research program focuses on integrating basic and applied research to develop improved management strategies for fruit diseases of concern to New York producers. In recent years, research endeavors in the form of plant biotechnology have made considerable contributions to the management of fruit diseases. However, efforts are still needed to improve the concepts and products of basic research so they may be more readily applied to solve disease problems. Hence, although much of my research is concerned with applied aspects of fruit diseases, a portion of my research program will be dedicated to conducting basic research in the hope of developing products with potentially broad or far-reaching applications.
Currently, my appointment is 20% extension, 30% Teaching, and 50% research. Because of this split, I endeavor to interweave my research program goals with those of my extension and teaching programs such that my research endeavors lead to stakeholder-relevant extension deliverables and illustrations of real-world teachable moments. In turn, I allow my student, grower stakeholder needs, extension concerns to guide my research efforts. Therefore, my research, teaching, and extension efforts focus on applied disease management for NY crops where accomplished have impacts and can be realized in short time frames.
To address both applied and basic research philosophies, and both research, teaching, and extension aspects of my appointment, I have established the following goals:
- Investigate the biology and management of fungal and bacterial diseases of apple, stone fruit, and small fruit using cultural, chemical, biorational, and organic approaches
- Understand the biology, epidemiology, and management of antimicrobial resistance in pathogen populations causing diseases of tree and small fruit crops.
- Enhance the adoption of precision agriculture forecasting & spectral imaging systems for plant disease.
Extension
New York State has a substantial fruit industry with apples being one of the premier fruit crops. According to the National Agricultural Statistics Service, New York ranks second in the nation in terms of total bearing acreage (~50,000 acres) and total utilized production value (~$250M USD). My extension goals are to develop educational programming and materials and to provide services for the diagnosis and management of fruit diseases in New York.
The specific goals of my program are to work with stakeholders, cooperative extension, private consultants, and regulatory agencies to
- Develop educational material and tools to improve the diagnosis and management of fruit diseases in NY and promote pesticide stewardship practices
- Provide services to help fruit stakeholders identify emerging disease concerns and overcome barriers to disease management specific to their operations.
There is considerable interrelation between the two goals as the products from my service-oriented goal will improve the relevance and quality of the educational materials and tools developed in the first. As the number of small, diversified farms and groups with interests in local farming increases, the educational tools and services provided by my program will be of critical importance for the sustainability of fruit crops in NY.
Teaching
Teaching is a relatively new component of my appointment and follows a job description revision stemming from a teaching need for my section of PPPMB. I have served as instructor of record at other institutions during my graduate postdoctoral position.
I serve as instructor for PLPPM 3010/5010 Biology and Management of Plant Diseases (3-credit hour course with a 1-credit hour lab. I also co-teach PLPPM 6820 Graduate Student Research updates (1-credit hour course) and PLSCS 4440/5440 Integrated pest management (3-credit hour course with a 1-credit hour lab). Given that I have limited agency to determine the structure and direction of PLPPM
For all my courses, I believe that deep information processing through active learning is the best means of retaining and being able to apply content. Through practice, I found that while my students learn considerably by actively engaging, the greatest amount of learning occurs when a student teaches or demonstrates a principle to another. My teaching goal is to capitalize on these concepts to develop engaged, thoughtful, and independent students who can apply the knowledge gained in class to solve real world issues. To achieve this goal, I endeavor to provide the following:
- Active learning: While students need to receive course content, working with and solving problems with course content is paramount to achieving learning. Laboratory exercises in diagnosis and management easily allow for active learning, but even lecture components that focus on flipped classroom problem solving can ensure that active learning occurs continually.
- Peer-teaching: I feel that students best learn when they are teaching another a concept or explaining principles to another. In my course, I use peer-teaching in group activities to allow students to teach or explain a principle or demonstrate a solution to a problem. While some group work in my courses is geared toward pure problem solving, peer-teaching components are always present.
- Inspiration/Motivation/Involvement: I work to promote excitement, curiosity, and independence from my students. I tend to use enthusiasm to motivate and inspire students to see the impacts or potential impacts of their learning. I make time at the beginning of class to acknowledge and celebrate the successes and accomplishments of my students and current events that impact student life. I step back and allow students to take the spotlight when possible. To maximize motivation, I endeavor to be present and engaged in all classes and labs even if TAs are leading exercises or teaching. Students appreciate accessibility of the instructor and I feel that being a positive presence facilitates their learning.
- Safety. While it’s important to have quantitative evaluations of performance in courses, deep learning can be impeded by concerns of academic failure and resulting punitive outcomes. I strive to reduce the impacts of formative assessments by conducting many low stakes formative assessments and combining these with other opportunities that award engagement and participation. My principal concern is lasting learning of plant pathology. Preparing and memorizing for single performance on a formative assessment is not an effective means of retaining knowledge. When students feel safe form academic punity, I feel that learning can be best achieved.
Peer reviewed publications from the last five years:
- Rea, M.S., Cox, K.D., Skinner, N.P., and Bullough, N.D. 2025. Effectiveness of TiO2 Nanoparticle Application for Treating Fire Blight in Apples. PhytoFrontiers. Accepted.
- Huang, J., Huyen, T.N.B.V., Liu, X., Mitra, S., Yu, M., Zeng, Q., Sundin, G.W., Cox, K.D., Förster, H., Adaskaveg, J.E., Kuo, C-H., Yuan, X., and Yang, C-H. 2025. RejuAgro A: A novel antimicrobial for fire blight control and beyond. Nature Comm. Accepted.
- Johnson, K., Kreis Douglas, R., Chester Allen, W., Yoder, K., Sherif, S.M., Cox, K.D., Jurick, W., Weber, A., and Villani, S.M. 2025. Evaluation of Fungicides for the Management of Glomerella Leaf Spot and Bitter Rot on Apple in North Carolina. Plant Disease. https://doi.org/10.1094/PDIS-12-24-2773-RE
- Luciano-Rosario, D., Castro, J., Peter, K.A., Cox, K.D., Fonseca, J.M., Gaskins, V.L., Jurick II, J.M. 2025. Mold in, mold out: Harvest bins harbor viable inoculum that can be reduced using novel sanitation methods to manage blue mold decay of apples. Postharvest Biology and Technology. 221: 113323.
- Yannuzzi, I.M., Cox, K.D. 2024. An evaluation of pruning programs to manage shoot blight, caused by the bacterium Erwinia amylovora. Plant Disease. https://doi.org/10.1094/PDIS-10-24-2144-RE
- Gdanetz, K., Dobbins, M.R., Villani, S.M., Outwater, C.A., Slack, S.M., Nesbitt, D., Svircev, A.M., Lauwers, E.M., Zeng, Q., Cox, K.D., and Sundin, G.W. 2024. Multisite Field Evaluation of Bacteriophages for Fire Blight Management: Incorporation of Ultraviolet Radiation Protectants and Impact on the Apple Flower Microbiome. Phytopathology. https://doi.org/10.1094/PHYTO-04-23-0145-KC
- Strickland, D.A., Londo, J., and Cox, K.D. 2023. Comparison of standard calendar GA4+7 plant growth regulator programs to applications timed to rainfall events for management of scarf skin, a fruit finish disorder of apple. Phytofrontiers. https://apsjournals.apsnet.org/doi/10.1094/PHYTOFR-07-23-0092-R
- Yannuzzi, I.M. Gadoury, D. M., Davidson, A., and Cox, K.D. 2023. Transient Nighttime Exposure of Apple Trees to Germicidal Ultraviolet Light Suppresses Blossom and Shoot Blight Caused by the Bacterial Pathogen Erwinia amylovora. Phytopathology. https://doi.org/10.1094/PHYTO-05-23-0151-SA
- Yuan, X. Sundin, G.W., Zeng, Q., Johnson, K.B., Cox, K.D., Yu, M. Jian, H., and Yang, C-H. 2023. Erwinia amylovora type III secretion system inhibitors reduce fire blight infection under field conditions. Phytopathology. https://doi.org/10.1094/PHYTO-04-23-0111-SA
- Gdanetz, K., Dobbins, M.R., Villani, S.M, Outwater, C.A., Slack, S.M., Nesbitt, D., Svircev, A.M., Lauwers, E.M., Zeng, Q., Cox, K.D., and Sundin, G.W. 2023. Multisite field evaluation of bacteriophage for fire blight management: disease control, incorporation of UVR protectants, and phage impact on the apple flower microbiome. Phytopathology. https://doi.org/10.1094/PHYTO-04-23-0145-KC
- DuPont, S.T., Munir1, M., Cox, K.D., Johnson, K., Peter, K., Baro, A. Evaluation of Pruning Therapies in Apple Trees with Fire Blight. 2023. Journal of Plant Pathology xx: xx-xx (accepted, pending revision).
- Strickland, D.A., Spychalla, J.P., van Zoeren, J.E., Basedow, M.R., Donahue, D., and Cox, K.D. 2023. Assessment of fungicide resistance via molecular assay in populations of Podosphaera leucotricha, causal agent of apple powdery mildew, in New York. Plant Disease. https://doi.org/10.1094/PDIS-12-22-2820-SR
- Jurick II, W.M., Messinger, L., Wallis, A., Peter, K.A., Villani, S., Bradshaw, M.J., Bartholomew, H.P., Buser, M., Acimovic, S.G., Fonesca, J.M., and Cox, K.D. 2022. PATHMAP (Pathogen and Tree Fruit Health MAP): A Smartphone App and Interactive Dashboard to Record and Map Tree Fruit Diseases, Disorders, and Insect Pests. PhytoFrontiers 2(4): 331-338.
- Jurick II, W.M., Choi, M.W., Gaskins, V., Peter, K.A., and Cox, K.D. 2022. Would you like wood or plastic? Bin material, sanitation treatments, and bin inoculum levels impact blue mold decay of stored apple fruit. Plant Disease 107: 1177-1182.
- Strickland, D.A., Ayer, K.M., Olmstead, D.L., and Cox, K.D. 2022. Refining management of apple powdery mildew in New York State with weather-based fungicide application programs. Plant Disease 107: 1425-1432.
- Strickland, D.A., Villani, S.M., and Cox, K.D. 2022. Optimizing use of DMI fungicides for management of apple powdery mildew caused by Podosphaera leucotricha in New York State. Plant Disease 106(4): 1226-1237.
- Strickland D.A., Hodge, K., and Cox, K.D. 2021. An Examination of Apple Powdery Mildew and the Biology of Podosphaera leucotricha (Ellis & Everh.) E. S. Salmon from Past to Present. Plant Health Prog. https://doi.org/10.1094/PHP-03-21-0064-RV
- Liu, Y., Kuo, J., Cox, K. Vanden Heuvel, J. Petersen, K. and Lal, A. 2021. Imaging and Detection of Botrytis Cinerea with Gigahertz Ultrasonic Imager, IEEE International Ultrasonics Symposium, IUS, https://doi.org/10.1109/IUS52206.2021.9593815.
- Wallis, A. and Cox, K.D. 2021. Examining Spatial Distribution and Spread of Fire Blight in Apple Orchards: Two Case Studies. Plant Health Prog. 22: 445-449.
- Dougherty, L.; Wallis, A.; Cox, K.; Zhong, G.-Y.; Gutierrez, B. Phenotypic Evaluation of Fire Blight Outbreak in the USDA Malus Collection. Agronomy 2021, 11, 144. https://doi.org/10.3390/agronomy11010144
- Ayer K.M., Strickland D.A., Choi M., and Cox KD. 2021. Optimizing the integration of a biopesticide (Bacillus subtilis QST 713) with a single-site fungicide (benzovindiflupyr) to reduce reliance on synthetic multi-site fungicides (captan and mancozeb) for management of apple scab. Plant Dis. https://doi.org/10.1094/PDIS-02-21-0426-RE
- Wallis, A. Gu, G., Reed, E. Ramachandran, R., Ottesen, A., Nou, X., and Cox, K.D. 2021. Endophytic bacterial communities in apple leaves are minimally impacted by streptomycin use for fire blight management. Phytobiomes. 5: 350-261
- Wallis, A. Yannuzzi, I.M., Choi, M., Spafford, J., Fenn, M., Ramachandran, P., Timme, R., Pettengill, J.B., Cagle, R., Ottesen, A., and Cox, K.D. 2021. Investigating the distribution of strains of Erwinia amylovora and streptomycin resistance in apple orchards in New York using CRISPR profiles: a six-year follow-up. Plant Disease. https://apsjournals.apsnet.org/doi/10.1094/PDIS-12-20-2585-RE
- Boucher, M., Collins, R., Harling, K., Brind’Amour, G., Cox, K.D., and Loeb, G. 2020. Interactions between Delia platura and Erwinia amylovora associated with insect mediated transmission of shoot blight. PhytoFrontiers. https://doi.org/10.1094/PHYTOFR-08-20-0013-R
- Willden S.A., Cox K.D., Pritts M.P., Loeb, G.M. 2020. A comparison of weed, pathogen and insect pests between low tunnel and open-field grown strawberries in New York. Crop Protection. Volume 139, 105388. https://doi.org/10.1016/j.cropro.2020.105388
- Lichtner, F.J., Gaskins, V.L., Cox, K.D, and Jurick II, W.M. 2020. Global transcriptomic responses orchestrate difenoconazole resistance in Penicillium spp. causing blue mold of stored apple fruit. BMC Genomics. 21:574. https://doi.org/10.1186/s12864-020-06987-z
- Wallis, A. E. and Cox, K. D. 2020. Assessing and minimizing the development and spread of fire blight following mechanical thinning and pruning in apple orchards. Plant Dis. https://doi.org/10.1094/PDIS-06-20-1324-RE
- Ayer KM, Choi M-W,Smart ST, Moffett AE, and Cox K.D. 2020. The effects of succinate dehydrogenase inhibitor fungicide dose and mixture on development of resistance in Venturia inaequalis. Appl Environ Microbiol 86: e01196-20. https://doi.org/10.1128/AEM.01196-20.
Contact Information
218 Barton Laboratory
Geneva, NY 14456
kdc33 [at] cornell.edu
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More information
School & Section
Graduate Fields
Education
- Doctorate
University of Georgia
2004
- Master of Science
University of Georgia
2000
- Bachelor of Science
Furman University
1998
- Doctorate
Kerik in the news
News
- Cornell AgriTech
- School of Integrative Plant Science
- Agriculture
Field Note
- Center of Excellence in Food and Agriculture
- Cornell AgriTech
- School of Integrative Plant Science