For eight years, a collaborative group of winemakers, scientists, growers and industry organisations have been keenly investigating which phylloxera-resistant grapevine rootstock performs best for Mornington Peninsula Pinot Noir.
They will soon have their answer, when a panel of wine sector experts assess wines made from the rootstocks under formal conditions at the University of Melbourne – ultimately determining their long-term winemaking prospects.
The wines – including five from the 2020 vintage and nine from the 2021 vintage have already been peer reviewed by a panel of Mornington Peninsula winemakers.
“This is the moment when we determine whether the consistently productive rootstocks we have identified can actually translate to high quality wine,” said Olivia Barrie, Chief Executive Officer of Mornington Peninsula Wine.
Since 2014, the Mornington Peninsula Pinot Noir Rootstock Trial – involving growers from across Greater Victoria – has been comparing the performance of Pinot Noir scions grafted to14 different rootstocks on two commercial vineyards 15 kilometres apart and with more than 100 metres elevation difference. One vineyard is located in a warmer coastal area of the Mornington Peninsula, while the other sits in a cooler more elevated location.
At both vineyards, Pinot Noir clone MV6 was grafted to 14 rootstocks with three replicates per treatment and one panel per replicate. Grapevines were also planted on their own roots as a control.
The research team then evaluated the treatments to determine which rootstock performed best under Mornington Peninsula conditions. This included measuring vine phenology, including the time of flowering and veraison, chlorophyll content, leaf area index, pruning mass, petiole nutrients and soil moisture at the three key stages of grapevine growth – anthesis, veraison and harvest.
“Preliminary data in the 2018–19 vintage showed clear differences in the timing of flowering, canopy size and plant nutrients, such as magnesium, sodium, potassium, calcium, phosphorus, sulfur, zinc, manganese, copper and boron; while in the 2020 vintage, most rootstocks showed faster veraison progress compared to own roots,” said Olivia.
“We’re now at the pointy end of the research project – a collaboration between Wine Australia, Wine Victoria, The University of Melbourne, the Australian Wine Research Institute, Mornington Peninsula Vignerons Association, Yalumba Nursery and CSIRO – to determine the long-term winemaking prospects of the rootstocks.”
The results of the formal sector tasting will form part of the study’s final report which will be published for industry in June 2022.
The report will be presented at the Australian Wine Industry Technical Conference in Adelaide in June 2022 along with a tasting of the wines.
The Mornington Peninsula Pinot Noir Rootstock Trial is funded by Wine Australia through Wine Australia’s Regional Program. For more information on the Regional Program visit here.