Vines get ‘anti-retroviral’ treatment

The ongoing wellness of vines and South Africa’s international reputation for producing wines of exceptional quality lie at the heart of an ambitious project using anti-retrovirals to free vines from the grip of leaf roll virus, which has already cost the country millions of rands. As is now recognised around the world, anti-retroviral drugs are effective medications for the treatment of infections in humans, primarily HIV, their plant equivalent now being applied to vines at the Somerset West wine farm, Vergelegen. The pandemic is specific to grape vines and affects most vineyards in the country. It is however much more manifest in red wines where it affects the quality and volume of the harvest. Eventually the vines become uneconomical and have to be uprooted. Andre van Rensburg, Vergelegen’s winemaker, and University of Pretoria academic, Professor Gerhard Pietersen, a world-renowned expert on leaf roll, have been working on the project for several years, during which time they have implemented a plan to dispose of infected vines and keep the replanted vineyards virus-free. Thus far, 120 hectares of vineyards have been uprooted and replanted at a cost of R75 000 a hectare, in what Van Rensburg calls ‘a war of attrition.’ The procedure is that once a vine is found to have the virus it is removed and those around it treated with the plant equivalent of anti-retrovirals, yielding a highly satisfactory result given that only one vine in 4 000 is found to have the disease in replanted vineyards. The leaf roll campaign has cost R30 million to date but Van Rensburg believes there will be a huge benefit in terms of wine quality as it continues to improve year after year. It’s also the only way to positively change South Africa’s wine image internationally. Hailed as an international breakthrough in wine industry terms terms, Vergelegen is receiving requests on the treatment from as far afield as New Zealand, Israel and the USA.