Tailored systems to chase yield potential
CSIRO researcher Dr Zvi Hochman has explored the potential for northern grain growers to increase wheat yields by 1.2 tonnes per hectare using best practice embodying current technologies and varieties suited to individual farming systems.
Speaking at the GRDC Grains Research Update in Coonabarabran, New South Wales, Dr Hochman said the key to achieving such a yield lift was using best practice to help achieve water-limited yields, instead of actual yields.
Water-limited yield is the yield potential determined by a given rainfall resource.
Dr Hochman said that between 1996 and 2010 the average wheat yield across the northern grains region was 1.7t/ha, which is less than half the region’s potential water-limited yield.
The northern figure is also 8.9 per cent lower than the average wheat yield in the western grains region, and 5.3 per cent lower than the average in the southern grains region.
Dr Hochman said leading growers from Victoria’s Wimmera and Mallee regions have demonstrated they can achieve 80 per cent of their water-limited yield.
“If we accept that growers can sustainably achieve a relative yield of 80 per cent, then this study suggests that growers in the northern grains region could achieve yields of 2.9t/ha,” he said.
“So there is scope to close the exploitable yield gap and increase average yields by 1.2t/ha.”
To help bridge the yield gap, Dr Hochman advocates tailoring best practice to individual farming systems, with a focus on using the “best-adapted crop varieties and best cropping and land management practices for a given environment”.
He also urged growers to benchmark productivity against their statistical local area (SLA).
With the exploitable yield gap varying from one SLA to the next, and from season to season, CSIRO researchers are developing a website showing ‘yield gap maps’ for farm locations as part of a GRDC-funded project.
As well as highlighting seasonal changes to water-limited yields across the northern grains region, the online maps are set to provide benchmarks for actual yields, water-limited yields, yield gaps and relative yields.
Dr Zvi Hochman, CSIRO
07 3833 5733
GRDC Project Code CSA00042
Region South, North