Periods of extreme high temperature, in particular short periods of heat shock, are a major threat to wheat yield and grain quality throughout much of the Australian wheat belt. The effects of high-temperature on yield and grain quality are well known but those traits underpinning plant response to high-temperature and the inheritance of tolerance are less well understood. An earlier GRDC project has successfully developed phenotyping protocols based on extensive field testing with controlled environment validation thereby overcoming a major bottleneck to genetic improvement. During that research new genetic variability for tolerance to high temperature has been identified.

This project combines these developed phenotyping procedures and populations, with wheat DNA marker technology and genomic selection approaches to significantly enrich wheat lines for heat tolerance. Using these approaches the current project has the following aims: (i) extensive phenotyping of already developed doubled haploid populations, or improved crosses from them, for field response to high temperature using both traditional and new phenomic methods; and (ii) calculation of genomic breeding values for heat tolerance to select the best crosses to generate the next generation of lines.