Dr Greg Rebetzke1, Dr Andrew Fletcher, Mr Timothy Green, Dr Kenton Porker, Dr John Kirkegaard
1CSIRO
Biography:
Greg undertakes research focused on implementing physiological and quantitative genetic understanding to fast-track delivery of elite wheat germplasm containing traits for improved adaptation to droughted and changing climates.
Abstract:
Climate change is forecast to significantly drive crop productivity and reliability in the future. To address this challenge, efforts are underway to guide future breeding efforts to adapt crop varieties to the environments and systems in which they will be grown. However, breeding relies on a strong and systematic signal to permit selection for important adaptation alleles and an assessment of the value (positive or negative) in the presence or absence of the predicted climate constraints. This provides a challenge to identify and fix important alleles particularly if the aim is to breed varieties able to resist the predicted combined risks of frost, heat and drought. Evidence to date has seen substantial variability in these climate extremes and their interactions (e.g. temperature × VPD) from one season to the next. For example, southern Australia has experienced every rainfall decile in the past decade alone. One approach to develop adapted crop varieties is to target traits that support opportunistic management in the wheat cropping system to ‘play the season’, effectively reducing business risk in current and future climates. Such traits can complement ongoing, longer-term and more challenging breeding efforts to identify traits that can resist specific climatic extremes. We report on studies targeting constitutively expressed ideotypes (e.g. high biomass, shorter-duration wheats for later sowing, increased rates of spike and grain-filling and increased coleoptile length) to establish their value to increase profitability of wheat systems in current and future environments. The genetics for these traits are understood, are available now and there are no expected costs to grain yield or quality in cooler, wetter seasons and being deployed in commercial breeding programs.