Water scarcity and plant disease

Impacts of water use strategies viewed through the lens of plant microbiology

In California, increased water scarcity is driving many agricultural producers to alter their water use practices. These changes include increased reliance on recycled water and low quality ground water (quality), and reduction of irrigation inputs (quantity). Our program at the University of California Davis seeks to demystify disease-risks related to changes in water quality and quantity, enabling producers to optimize water use and minimize disease losses.

Research themes:

  • Pathogen predisposition risks factors associated with saline groundwater and deficit irrigation
  • Effects of irrigation practices on opportunistic pathogens in the rhizosphere
  • Effects of water use on defensive mutualisms
  • Enabling water recycling: Management of pathogens in the water recycling chain
  • Using water saving methods to co-manage plant pathogen survival and spread
  • Biological approaches to mitigate disease risks associated with water use

Current Projects

Co-managing deficit irrigation-disease interactions to optimize water conservation and productivity in processing tomatoes

Lead PI: Cassandra Swett; CoPIs: Mallika Nocco, Tom Turini, Amisha Poret-Peterson

Funded by USDA-California Specialty Crop Block Grant Program

Recent Publications

Beaulieu, J., Nocco, M. and Swett, C.L. 2022. Effects of water scarcity-driven irrigation practices on disease management in California processing tomato. Acta Horticulturae.

Del Castillo Múnera, J., Poret-Peterson, A. T., & Swett, C. L. 2022. Changes in fungal and oomycete community composition following irrigation reductions aimed at increasing water use efficiency in a containerized nursery crop. Phytobiomes Journal, (ja)

Beaulieu, J., Belayneh, B., Lea-Cox, J. D., & Swett, C. L. (2022). Improving Containerized Nursery Crop Sustainability: Effects of Conservation-driven Adaptations in Soilless Substrate and Water Use on Plant Growth and Soil-borne Disease Development. HortScience, 57(6), 674-683. DOI: https://doi.org/10.21273/HORTSCI16459-21

Hellman, E.M. 2020. Assessing the Risks Associated with Increasing Irrigation and Soil Salinity on Fusarium Wilt (F. Oxysporum f. Sp. Lycopercisi Race 3) in California Processing Tomatoes, (Masters Thesis, University of California, Davis)

Swett, C.L. 2020. Managing crop diseases under water scarcity. Annual Review of Phytopathology, 58(16): 1-16.20.

Del Castillo, J., Bellaneh, B., Lea-Cox, J., Ritsvey, A., Koivunen, E.E., Swett,C.L. 2019. Identifying and managing disease risks associated with reducing irrigation in greenhouse Poinsettia production. Agricultural Water Management, 226: 105737

Del Castillo, J., Belayneh, B., Lea-Cox, J. and Swett, C.L. 2019. Effects of set- point soil moisture control on oomycete disease risk in containerized plant production, based on the tomato- Phytophthora capsici model system. Phytopathology, 109(8): 1441-1452