Issue link: http://www.epageflip.net/i/1093876
3 A L M O N D O R C H A R D 2 0 2 5 G O A L S PEST MANAGEMENT Bloom, Post-Bloom Almond Disease Management With the presence and passing of bloom comes the promise of a new crop — and the threat of infectious diseases, especially if a wet spring occurs. Poor disease management will lead to significant yield losses and even tree losses later in the growing year. To assess and manage early spring diseases, growers must consider the possible impacts of management practices on water quality — keeping in mind the potential for run-off when it rains and/or spray drift — as well as international maximum residue limits and, during bloom, the impacts on honey bees and other pollinators. The Almond Board of California, in partnership with the University of California, UC Cooperative Extension and USDA-ARS, has been continuously funding research focused on improving the industry's understanding of how to best prevent and manage diseases. Dr. Jim Adaskaveg, a professor and plant pathologist at the University of California, Riverside, has been a longtime researcher of foliar and bloom diseases in almonds and other Prunus species. In his research, he advises growers continue to keep an eye out for the main bloom diseases throughout the season. Main diseases include: brown rot (Monilinia), anthracnose (Colletotrichum), shot hole (Wilsonomyces), green fruit rot (or jacket rot) and gray mold (Botrytis/ Sclerotinia/Monilinia). One facet of Adaskaveg's research involves evaluating the effectiveness and timing of new products to combat these diseases; currently, there is a range of registered and trial products available. Results from the latest efficacy trials were shared during Adaskaveg's presentation at The 2018 Almond Conference. His slides, titled "Speed Talks: Pest Management," are available at Almonds.com/ ConferencePresentations. Adaskaveg's research also monitors development of resistance in key almond diseases, such as brown rot and jacket rot. In some trials, resistance developed within three years of a new mode-of- action fungicide for almonds being introduced to the market. Thus, growers should carefully review the FRAC (Fungicide Resistance Action Committee) grouping, found under the "Fungicide Resistance Management" page for almonds on ipm.ucanr.edu, and refer to the mode of action categorization of each fungicide planned for use to ensure they are truly rotating between different modes of action. Adaskaveg's research also provides suggestions for possible rotations. As always, growers must keep the principles of Integrated Pest Management (IPM) top of mind — that is, they must consider what can be done to prevent a pest problem, monitor for the issue and then choose the appropriate tool when control is necessary. For more on how to implement various IPM strategies, visit the "Growing Safe Product" page at Almonds.com/Growers. Jim Adaskaveg, Ph.D. Professor and Plant Pathologist University of California, Riverside