Remote hyperspectral imaging of grapevine leafroll-associated virus 3 in cabernet sauvignon vineyards

Over the span of two years we monitored five Cabernet Sauvignon vineyards: ground surveys recorded the incidence of visual symptoms of disease in the field during the same months in which hyperspectral maps recorded disease incidence from the air. A customized Geographic Information System (GIS) methodology was developed to compare the visual symptoms to the results of the hyperspectral imaging technique. For a select number of vines, disease incidence was then confirmed by laboratory assays. On average, detection sensitivity was 94.1%, with a range of 88% to greater than 99% per vineyard. Various vineyard-specific factors appear to compromise detection sensitivity. Overall, our results show that remote hyperspectral imaging of GLRaV-3 infected Cabernet Sauvignon vineyards can be a useful and cost-effective approach to mapping diseased vines. Future studies should focus on the use of this tool for detecting GLRaV-3 in other grape varieties, as well as other grapevine pathogens.