Correct strategy the key to assessing disease risk
Grain growers across New South Wales and Queensland are being reminded to follow updated sampling techniques when assessing the risk of disease threats including crown rot and root lesion nematodes.
Crown rot is caused by the fungus Fusarium pseudograminearum and is one of the most serious disease threats to winter cereal crops in Australia.
DNA-based soil test PreDicta B® is recognised as a reliable technique for identifying the level of risk for crown rot, and other soil-borne pathogens within paddocks prior to sowing.
Research funded by the Grains Research and Development Corporation (GRDC) and conducted by the South Australian Research and Development Institute (SARDI) and the NSW Department of Primary Industries (DPI) has helped boost the reliability of the PreDicta B® test.
NSW DPI senior plant pathologist Dr Steven Simpfendorfer said PreDicta B® required a dedicated sampling strategy.
“Collect two cores of 1 centimetre diameter and 15 centimetres deep from each of 15 different locations within the target paddock or production zone,” he said.
“Samples may be taken to a 30cm depth in the northern region if growers are concerned about Pratylenchus thornei (root lesion nematodes) detection.
“If using a larger diameter core or coring to 30cm, take fewer cores per location.
“Take the soil cores from along/in the rows of the previous cereal crop if still visible and retain any stubble collected by the core. Most soil-borne pathogens are concentrated under the rows of the last cereal crop.”
Dr Simpfendorfer said sampling depth, whether it be 0 to 15cm or 0 to 30cm, did not appear to greatly impact on detection of the various pathogen levels in the northern region when the collection of cores was targeted at the previous cereal rows.
“If the rows cannot be seen, take the cores at random. Add two pieces of cereal stubble, if present, to the sample bag at each of the 15 sampling locations to improve the detection of crown rot.
“Each piece should be a single dominant tiller from the base of different plants and include the crown to the first node. Discard material from above the first node.
“The maximum sample weight should not exceed 500 grams.”
To organise your sampling kits, or for more information on the PreDicta B® tests check the SARDI website or contact Crown Analytical Services on 0437 996 678.
PreDicta B® testing will be discussed at the upcoming GRDC Grains Research Updates at Coonabarabran on February 23-24 and Goondiwindi on March 1-2.
For InterviewsBernadette York, NSW DPI media officer
0427 773 785
ContactEllen McNamara, Cox Inall Communications
0429 897 129
GRDC Project Code DAS00137, DAN00175