Identification of wild barley derived alleles associated with plant development in an Australian environment

The objective of this study was to explore wild barley as a potential source of alleles controlling plant development that can be used to improve the adaptation of barley to the Australian environment. The HEB-25 population was evaluated in field conditions at Strathalbyn (South Australia) in 2015 and 2016 and phenotyped for five traits related to plant development, in addition to plant height and ear number. GWAS identified QTL for all traits, of which many co-localised with known phenology genes. In the Australian environment, it was found that the Gibberellic acid (GA)-dependant pathway is important in regulating key development stages including shooting, flowering and maturing compared to the photoperiod and vernalisation pathway. Beneficial alleles from wild barley were identified, such as at the QTL tightly linked to the swd1 locus belonging to the GA-dependant pathway, wild alleles from five subfamilies increased EAR by up to 2.23 ears per m2. At the identified QTL, a wide range of effects was observed due to the wild barley alleles thus providing new genetic diversity that can be utilised to fine-tune the adaptation of barley to the Australian environment.