GADx’s Rapid Diagnostic Test, BotrytisAlert, Demonstrates Utility Across Wine Production System

Global Access Diagnostics (GADx), announced it has expanded the applications of its low-cost, rapid diagnostic test, BotrytisAlert. Harnessing GADx’s expertise in lateral flow technology, the test has shown to detect and measure the fungal crop pathogen Botrytis across several critical points in wine production; in the vineyard, in grape must and in finished wine. Early intervention in the disease cycle facilitates improved efficacy of sustainable control measures and to reduce unnecessary use of fungicides.

Launched in 2020, BotrytisAlert is a rapid antigen test originally developed for the soft fruit industry to monitor Botrytis spores, or bunch rot, in air samples to drive early warning of disease potential on exposed crops. In soft fruit, the test has been used to forecast infection risk, guide the timed application of control treatments ahead of symptom development, inform quality and drive crop post-harvest management decisions. BotrytisAlert has since been evaluated by both the North and Southern hemisphere wine industries and demonstrated to be simple-to-use, fast, and accurate for quantifying the Botrytis fungus in grape must and finished wine, in addition to directly on the vine. Effective for use prior to transport and also at the wine pressing centre, the test is read at 10 minutes either visually or using a simple, low cost, small portable reader which can fit in the palm of the hand.

Globally, in the wine sector it is estimated, on average, 25% of turnover is lost due to Botrytis rot, at a cost to the industry of €15 billion per year. Botrytis is considered one of the most serious diseases of grapevine affecting not only yield, but grape quality and taste. In the UK’s horticulture sector, the fungus infection is the second greatest cause of crop loss by reducing harvest yields and marketability, estimated to cost £54 million. Primarily affecting strawberries (£15-30 million losses) but also cut flowers (£24 million), tomatoes, onions, hardy nursery stock and ornamentals.

As part of an Innovate UK funded initiative¹, BotrytisAlert was developed and trialled with Berry Garden Growers, NIAB EMR and the Warwickshire College. It is part of GADx’s wider crop protection diagnostic portfolio, to include other fungal pathogens such as Rhizopus and Mucor.

Dr Alison Wakeham, Head of Non Human Contract Research and One Health, GADx, commented: “Botrytis, or bunch rot, is a worldwide problem for the wine industry, particularly when rain falls close to harvest; impacting yield, wine quality and taste,” She added: “As for the treatment of human diseases, early intervention is key for the health of our crops, livestock and fisheries. In crop production, BotrytisAlert offers the potential to monitor infection potential and alert growers to deploy control strategies at the right time and only when needed. And at harvest, to measure quality and post- harvest rot potential. Botrytis concentration in wine grapes is used as an essential quality marker; as a rule of thumb, red table wine can tolerate grapes that are up to 10% botrytised without affecting taste. But, for sparkling wines the fungus can impact bubble quality and lower thresholds of 3-5% maybe required.”