June 18, 2012
Disease management will be paramount this season for northern region chickpea growers and researchers warn complacency is the biggest risk to yield and crop health.
Dr Kevin Moore, NSW Department of Primary Industries (NSW DPI) special plant pathologist (pulses and oilseeds), Tamworth, NSW urges growers to follow key disease management recommendations.
“Even though Ascochyta and Botrytis grey mould did not cause widespread losses in 2011, the pathogens are endemic in the region and complacency is the greatest risk to 2012 crops,” Dr Moore says.
He told advisers and growers at the Grains Research and Development Corporation (GRDC) Updates that planting high quality seed that has been properly treated with a registered seed dressing is the first step in disease management.
GRDC invests in more profitable chickpea production via research projects on disease screening and management, pest management and agronomy. It also supports the national chickpea breeding program and has been instrumental in the development and release of three new varieties recently for the northern region.
Dr Moore says Ascochyta trials carried out last year at NSW DPI’s Tamworth Research Station confirmed PBA HatTrick’s robust Ascochyta rating and demonstrated PBA Boundary and other new lines have even better resistance to the disease.
He says growers need to support this genetic disease resistance with strategies to reduce losses from Ascochyta. These include:
• Spray all varieties with less Ascochyta resistance than PBA HatTrick with a registered Ascochyta fungicide prior to the first rain event after crop emergence, three weeks after emergence, or at the three-branch stage of crop development, whichever occurs first.
• For paddocks that had chickpeas in 2010, spray all varieties including PBA Boundary and PBA HatTrick , prior to the first rain event after crop emergence, three weeks after emergence, or at the three-branch stage of crop development, whichever occurs first.
• In paddocks that have not had chickpeas for at least two years, PBA Boundary , PBA HatTrick and most GenesisTM lines should not require their first Ascochyta spray until the disease is detected. Monitor these crops two to three weeks after each rain event from emergence onwards and spray if Ascochyta is detected in the crop or is found in the district on any variety.
• For all varieties with less Ascochyta resistance than PBA HatTrick and for varieties with Ascochyta resistance as good as or better than PBA HatTrick but where Ascochyta has been detected, apply a second spray before the second post-emergence rain event. In 2011, crops that were sprayed on this schedule had the least Ascochyta and subsequent management was successful.
• Ground application of fungicides is preferred. Select a nozzle such as a DG TwinJet or Turbo TwinJet that will produce no smaller than medium droplets (ASAE) and deliver the equivalent of 80–100 litres water/hectare at the desired speed.
• Where aerial application is the only option (e.g. wet weather delays) ensure the aircraft is set up properly and that contractors have had their spray patterns tested.
To download the GRDC Update paper, visit www.grdc.com.au/updates.