First year results from a project trialling the use of ultraviolet light in vineyards to reduce fungicide dependency show promise but more research is required.
The Bragato Research Institute (BRI)-A Lighter Touch (ALT) project, supported by Agri Automation Ltd and Whitehaven Wines, trialled UV-C technology in Sauvignon blanc grapes for control of powdery mildew. The UV-C light treatment was applied with a UVEX system coupled with a Burro autonomous mobile robot.
UV-C light treatment being deployed in a vineyard.
In sharing the first year findings, BRI reported weekly applications (every five days) of UV-C light alone at the dose of approximately 120 J/m2 effectively controlled powdery mildew on Sauvignon Blanc up to pre-bunch closure. From veraison to harvest, the control was moderate but not at a level comparable to the grower’s fungicide spray programme.
An excellent level of control was achieved even when the standard fungicide programme was reduced by 50% either with or without UV-C applications, highlighting opportunities to improve and optimise current spray practices. Further research is needed to improve the efficacy of UV-C by increasing the irradiance dose, frequency, penetration, and coverage, as well as determining the optimum combination with fungicides.
Grapes with powdery mildew. Credit: BRI
