Malcolm Hobbs, Monica Cooper,* Selena Vengco, Michelle Moyer, Stephanie Bolton, and Larry Bettiga
*University of California Cooperative Extension Napa County, 1710 Soscol Avenue, Napa, CA, 94559 (mlycooper@ucanr.edu)

Leafroll and red blotch are the most consequential viral diseases of grapevine in North America. Disease management integrates prevention, avoidance, monitoring, and selective suppression tactics. Because disease management is knowledge- and resource-intensive, an improved understanding of these factors could improve adoption of management tactics. Towards that end, we conducted a survey (n = 154) and interviews (n = 42) with industry professionals involved in the decision-making process of virus management in California and Washington vineyards. Nine economic, technical, and social-behavioral factors, along with 24 sub-factors, were identified as influencing adoption. Economic factors were impact of disease on yield, ability to sell infected product, and the costs of management. Technical factors were availability and acquisition of disease knowledge and the efficacy of extension and outreach ac­tivities. Social-behavioral factors included internal organizational processes, govern­ment subsidies, regulatory practices, and regional collaboration. Context determined how each factor affected adoption and there was an interplay between factors that underscores the complexity of decision-making and management. These studies provide context for the agricultural industry, research scientists, extension educators, and other supporting partners of the financial, interpersonal, and technical issues that must be overcome to successfully manage grapevine viral diseasess.

Funding Support: California Department of Food and Agriculture, Pierce’s Disease and Glassy-Winged Sharpshooter Program, CDFA Agreement Number 19-0271-000-SA