Murray Valley Regional Program delivers important vineyard trial results
A huge 2013–14 GWRDC Regional Program is proceeding in Australia’s second largest production zone, the Murray Darling and Swan Hill wine regions.
A number of growers and vineyards have been enlisted to help gather data for several ongoing projects, looking at irrigation, nutrient levels and disease control.
Murray Valley Winegrowers Inc (MVWI) industry development officer Liz Singh said vintage also means a very busy time collating data at one of the peak periods in the GWRDC-funded Regional Program.
Water use efficiency benchmarking
Now in its third year, almost 35 vineyards are involved in recording data in a water-use efficiency project.
The project is gathering water use efficiency data in four varieties (Chardonnay, Shiraz, Cabernet Sauvignon and Gordo) under two irrigation types (low level sprinklers and drip)
‘The project is in its final year now, and has also included recording the data at four different growth periods: bud burst, veraison, harvest and post-harvest’, she said.
‘It’s chiefly looking at examining water use efficiency and the potential water savings growers could make in the region.
‘The final report will use and contrast all three years of data and we’ll also produce a regionally-focussed irrigation factsheet later this year.’
Minimising disease in the vineyard
Held annually, Mrs Singh said the minimising disease workshops and field days usually held around October are always well attended.
The 2013 workshop examined specific chemicals for use in preventing vineyard diseases and preventative spray programs.
The workshop was followed up with four field-based events. Peter Magarey from Magarey Plant Pathology examined the key control points for disease in the vineyard while Chris Dent updated growers on the best practice for sprayer set up, hitting the target and ensuring disease prevention in the vineyard.
‘About 70 growers attended the first sit-down workshop, with another 70 then attending one of the four follow-up field visits we held across the Murray and Swan Hill regions’, she said.
Vineyard nutrient removals
A project examining the nutrient content of canes, leaves and fruit at three different growth stages, is seeking new insights into the vitality of the grape crop throughout the season.
In its second year, the project is being run across eight trial sites and two grape varieties, Chardonnay and Shiraz.
‘We’ve removed about 1.5m of vine at flowering, veraison and harvest and we’re analysing the nutrient levels of the cane, leaves and fruit from each vineyard’, she said.
‘The end result, we hope, will be a greater understanding of the vine’s nutrient levels and needs at the critical growing stages of the vine.
‘We also think we will be able to use this information to design specific fertilisers that will match the variable nutrient needs of vines throughout the year.’
CSIRO senior research scientist Chris Davies was enlisted earlier in the year to share his knowledge around berry maturity.
The Advance Viticulture workshops, held annually, are designed to give growers a more complex and technical understanding of specific viticulture issues, Mrs Singh said.
‘This year, we had about 35 growers attend the half-day workshop, with Chris presenting some excellent information around berry maturity’, she said.
An ongoing root chamber project is providing some exciting results, according to Mrs Singh.
Now in its third year, chambers have been positioned in vineyards across the Murray Valley with regular updates and images posted to the Murray Valley Winegrower website.
The project is looking at the growth of feeder roots for nutrient uptake between budburst and flowering. As a result, it’s shown that the new white root growth (needed for nutrient uptake) is most active closer to flowering.
‘Most growers know that fertilising post-harvest is important, but there was still quite a lot of confusion over what the best timing was for additional fertiliser, between budburst and flowering.
‘We’ve been able to show that the best time for fertilising is closer to flowering – any time before that is really of no value to the vines.’
Also, just getting underway in time for vintage are three new GWRDC-funded projects.
The trials will look at developing a weather alert for botrytis conditions (similar to the current downy mildew alerts); more nutrient research, which will look at how quickly the vines take up nutrients; and a project that is looking at the effects of adding oxygen into irrigation water.