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.