A Wine Australia funded Incubator Initiative research project has identified several grapevine rootstocks that may offer advantages in timing of flowering, canopy and plant nutrients for Pinot Noir growers.
The findings are another piece in the puzzle of identifying the rootstocks best suited to the Mornington Peninsula for producing ultra-premium Pinot Noir that is tolerant to phylloxera, drought and salinity.
Lead researcher Dr Pangzhen Zhang, from the School of Agriculture and Food at the University of Melbourne, said phylloxera and drought-resistant rootstocks provided a viable solution.
Working as part of a collaborative team, the project compared the effects of 14 different rootstocks on the physiological performance of Pinot Noir scion.
The study was conducted at two commercial vineyards five kilometres apart in the Mornington Peninsula region. One vineyard is located in a warmer coastal area, while the other is in a cooler, more elevated location.
At both vineyards, the scions of V. vinifera L. cv Pinot Noir (clone MV6) were grafted onto 14 rootstocks in 2014 and 2016 with 3 replicates per treatment and 1 panel per replicate. Own-rooted Pinot Noir was also planted as a control.
The research team then evaluated the rootstocks in 2018–19.
‘We measured plant phenology, plant physiology, plant and soil parameters, 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’, said Dr Zhang.
Preliminary data in the 2018–19 vintage showed clear differences in the timing of flowering, canopy size and uptake of plant nutrients, such as magnesium, sodium, potassium, calcium, phosphorus, sulfur, zinc, manganese, copper and boron.
Dr Zhang said based on the current results, the team can perform preliminary evaluations of the performance of some rootstocks.
‘Preliminary evaluations suggest that some rootstocks – such as 3309C and 5BB Kober – produce more scion vigour than for example 110 Richter, while some rootstocks such as 1103 Paulsen and 5BB Kober enhance uptake of nutrients’, he said.
He said further investigations were warranted to validate the results reported in the current study.
The next stage of the research will continue through the Incubator Initiative for a second year and include an analysis of grape composition, wine composition and wine sensory assessment.
Dr Zhang said the research will benefit the wider Australian wine sector.
‘Rootstocks are used to increase tolerance to soil-borne pests and diseases, such as phylloxera, but can also be used to manage scion performance, especially canopy growth and yield, and to manage tolerance to abiotic stress, such as drought and salinity, and grape quality.'
‘It would be wise to use rootstocks when planting new vineyards to protect from the threat of phylloxera.’
He said the adoption of new rootstocks could also help grapegrowers manage future water scarcity and overcome soil health problems such as soil salinity and sodicity.
The project is a seven-way collaboration between Wine Australia, Wine Victoria, The University of Melbourne, The Australian Wine Research Institute, Mornington Peninsula Vignerons Association, Yalumba Nursery and CSIRO.
The final report from this project can be found here.