Рет қаралды 143
Climate change is forecast to significantly drive crop productivity and reliability to affect global food security 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, successful breeding relies on a: (1) strong and systematic signal to permit selection for important adaptation alleles; and, (2) an established value proposition for environmental constraints poorly understood in terms of frequency and intensity. Together, these challenges risk significant cost in time and effort targeting alleles for ‘resistance’ to individual environmental constraints (ie frost, heat and drought) and ignoring the potential for crop damage through combinations of these. Evidence to date has seen substantial variability in these climate extremes and their interactions (e.g. temperature × VPD) from one season to the next with southern NSW experiencing 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 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 novel traits and new genetics that can resist specific climatic extremes. I will 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, and are available now, and there are no expected costs to grain yield or quality in cooler, wetter seasons. I will also discuss the potential to mitigate risk by breeding traits that allow other economic uses of crops unavoidably and inevitably damaged by heat, frost or drought such as awnless, milling wheat varieties suitable for domestic and export hay.
Dr Greg Rebetzke, Chief Research Scientist at CSIRO Agriculture and Food, contributes to the understanding of genetic and physiological factors affecting water productivity and adapting to changing climates in rainfed winter cereals. His goal is then to deliver elite trait-containing germplasm, and improved phenotyping and genetic methods for trait enrichment in commercial breeding programs. Greg contributes to a number of grower and scientific advisory committees. He serves as an editorial advisor on key international journals while serving as an editor on the Journal of Experimental Botany. Greg also supervises in the training of students and postdoctoral researchers. As a leader in CSIRO Agriculture and Food, Greg works closely with Australian commercial breeding programs to deliver improved crop performance in new varieties released to farmers. His research has delivered to new commercial wheat varieties and breeding methodologies used in Australia and overseas. He links strongly with regional agronomists to identify opportunities and facilitate delivery in farming systems relevant to current and future climates, and in reducing the cost and risk of grain production while increasing grower profitability and sustainability.