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ARS Home » Pacific West Area » Corvallis, Oregon » Forage Seed and Cereal Research » Research » Publications at this Location » Publication #379164

Research Project: Breeding, Genomics, and Integrated Pest Management to Enhance Sustainability of U.S. Hop Production and Competitiveness in Global Markets

Location: Forage Seed and Cereal Research

Title: Delayed early season irrigation: impacts on hop yield and quality

Author
item Gent, David - Dave
item CLAASSEN, BRIANNA - Oregon State University
item MASSIE, STEPHEN - Washington Hop Commission
item Phillips, Claire
item SHELLHAMMER, THOMAS - Oregon State University
item Trippe, Kristin
item TWOMEY, MEGAN - Oregon State University

Submitted to: Journal of the American Society of Brewing Chemists
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/12/2021
Publication Date: 4/30/2021
Citation: Gent, D.H., Claassen, B.J., Massie, S.T., Phillips, C.L., Shellhammer, T.H., Trippe, K.M., Twomey, M.C. 2021. Delayed early season irrigation: impacts on hop yield and quality. Journal of the American Society of Brewing Chemists. 79. https://doi.org/10.1080/03610470.2021.1915053.
DOI: https://doi.org/10.1080/03610470.2021.1915053

Interpretive Summary: Irrigation is essential for hop production in the primary growing regions in the western U.S. Irrigation water supplies can be inadequate in drought and likely will become more variable in the future due to climate variability and increasing demand for water from non-agricultural uses. In this research, we evaluated the impact of short duration drought by created varying levels of short-term water stress in two cultivars, Cascade and Zeus, through delaying the first irrigation of the season by one to three weeks. The experiments were repeated over three years. The impact of delayed irrigation depended on year and cultivar, with larger impacts on yield of Cascade as compared to Zeus. In Cascade, yield was decreased when the timing of the first irrigation was delayed. However, cone quality factors overall were similar between irrigation treatments. In Zeus, delaying the first irrigation did not have detectable effects on brewing quality or yield in any individual year or when data were aggregated over all years. Thus, while early season drought conditions may substantially reduce yield, these effects are cultivar dependent and impacts on brewing quality appear small or undetectable.

Technical Abstract: Irrigation is essential for hop production in Oregon and Washington states, the primary growing regions in the U.S. Irrigation water supplies can be inadequate in drought and may become more variable in the future due to climate variability and increasing demand of water for non-agricultural uses. In this research, we evaluated the impact of delayed timing of the first irrigation of the season on hop yield and cone quality metrics in the cultivars Cascade and Zeus over three years. The impact of delayed irrigation depended on year and cultivar, with larger impacts on yield of Cascade as compared to Zeus. In Cascade, yield decreased 10.8% to 16.2% when the timing of the first irrigation was delayed by 10 or 18 days after training, respectively. However, cone quality factors were statistically similar when data were aggregated over all three years. In Zeus, delaying the first irrigation did not have detectable effects on brewing quality or yield in any individual year or when data were aggregated over all years. Thus, while even a brief delay in irrigation may substantially reduce yield in some cultivars such as Cascade, these effects are cultivar-dependent and impacts on brewing quality appear small or undetectable.