Yield gaps in rainfed crops remain large enough to suggest considerable scope for increasing prevailing yields at the farm level, according researchers at The University of Western Australia.
Adjunct Professors Walter Anderson and Chris Johansen, and Professor Kadambot Siddique from The UWA Institute of Agriculture critically reviewed the rainfall-limited potential yields and the gap between actual or average yields of cereal and grain legume crops.
They found there is still substantial room to increase the yield in farmers’ fields in rainfed cropping systems in both developed and developing regions.
Professor Kadambot Siddique said that as the supply of suitable water for irrigation and available land nears global limits, increased grain production will need to rely on increasing yields in rainfed cropping regions.
“Research on yield improvement will deliver a greater contribution to food security if the focus is on regions where food supplies are in deficit,” Professor Siddique said.
“In developing agriculture, there is scope for relatively well-established genetic and agronomic means of yield improvement, but more emphasis can be given to strategic means to ensure sustainability of yields.”
The researchers suggested that breeding for yield stability through disease resistance, and for profit stability through improved quality, should be the main focus for breeders to help close the yield gap.
Future agronomic research aimed in part at improving the ability of farmers to adjust tactical management according to seasonal conditions should be a priority.
“Average rates of genetic yield improvement in cereal crops grown under non-limiting conditions have been estimated at less than 1%,” Professor Siddique said.
“The skills of farmers in responding to environmental variability, including tactical management and choice of cultivars has had a big impact in improving yields.”
Strategic management revolving around soil improvement may take some years to be fully effective but will contribute to longer-term production stability.
The research Addressing the yield gap in rainfed crops: a review was recently published in Agronomy for Sustainable Development.
Hackett Professor Kadambot Siddique (+61 8) 6488 7012
Diana Boykett (Communications Officer, The UWA Institute of Agriculture) (+61 8) 6488 3756 / (+61 4) 04 152 262