Final Report – 2023 Funding Cycle (one year project)

Principal Investigator: Pete Jacoby, Washington State University,Pullman

Telephone: 509-475-7630

Cooperators: Patrick Rawn, Dineen Vineyards, Zillah, Washington

Summary: Rogueing of virus-infected vines followed by replanting with healthy cuttings or young plants is practiced for managing virus diseases in vineyards. Replacement of virus infected vines with healthy cuttings often results in retarded growth of replants because of competition from nearby established vines. 

The project was initiated during the late summer of 2020 within a 3-year old planting of Merlot grapes within Charlotte’s Block in Dineen Vineyards north of Zillah, WA. This block had been earlier rogued to remove vineyards showing evidence of Red Blotch virus and new replacement vines had been planted earlier in the year. Pairs of these replacement vines were selected when in close proximity to one another and DRZ delivery tubes were installed at a depth of 18 inches near the base of one of the pair to apply subsurface drip irrigation while the other received surface drip irrigation at the same rate of water delivery. A second site was intended to be installed but a cooperator was not found. 

After three years of observation and collection of end-of-season measurements of growth in replacement vines, no significant differences were found among growth/development of vines irrigated by either irrigation method (surface drip or subsurface drip).

Irrigation // Viticulture //