Grape growing is a risky business, and insidious invaders—viruses and other pathogens—are nearly impossible to detect until they show up in the vineyard. The economic costs incurred from vine and fruit damage by viruses and graft-transmissible pathogens routinely reach billions of dollars annually (Mannini and Digiaro, 2017). In the days before robust grapevine disease testing, growers took a gamble every time they planted new stock, relying on luck and trusted nursery operations to provide pathogen-free plants.
Today, the National Clean Plant Network (NCPN) program with funding from USDA, helps support clean plant Centers that produce and maintain virus-tested, foundation grape vine stocks. After stocks are "cleaned" of selected viruses and pathogens, Centers propagate the material to sell and distribute to nurseries and growers.
The promise of lower disease pressure is certainly desirable to fruit growers, but is it worth the cost to taxpayers? Recently, Cornell researcher Jie Li calculated the return on public investment for the Foundation Plant Services (FPS) in California, the foremost NCPN Center for grape stock in the U.S. The benefit-to-cost ratios calculated under two different scenarios was significant, with each dollar returning $22 to $96 in economic benefits, depending on estimated disease severity (Li et al. 2022). Read the entire paper here.