Coalition to trounce root diseases

PRECISION AGRICULTURE (PA) techniques are lining up with soil sampling techniques in a new offensive against root diseases.

Take-all, cereal cyst nematodes and root lesion nematodes cost the Australian grains industry millions of dollars a year in reduced production.

PA enables farmers to identify high- and low-yielding areas in paddocks through the · use of GPS-linked yield monitoring equipment and electromagnetic surveys. Having done this, the idea is to find out the causes of yield variations and, if remedies are possible and practical, to implement them.

John Heap of the SA Research and Development Institute (SARDI) believes that crop root diseases are one of the causes of yield variations in paddocks.

"SARDI's Field Crops Pathology Diagnostic Group has recently demonstrated that diseases are associated with particular production zones within paddocks, in the same way that, for example, there are variations in nutrient levels, or in soil types themselves," Dr Heap said.

With support from growers and the Federal Government through the GRDC, the SARDI group has begun research to combine PA with soil tests to better understand and manage soil-borne diseases.

Earlier this year, PA techniques were used to divide 22 paddocks on farms in SA into three production zones. Samples were taken from each zone in the 22 paddocks and tested for soil diseases. "There was at least one disease in every paddock that was higher in some production zones than in others;' Dr Heap said.

"The ongoing research aims to identify the most efficient soil sampling strategies, determine which paddock data layers are most useful for disease mapping, reduce the risk of disease losses in PA systems and lay the groundwork for future attempts at site-specific disease management.

Program 4 Contact: Dr John Heap 08 8303 9444 email heap.john@saugov.sa.gov.au