Alexander von Humboldt Foundation has sponsored the research project of Dr. Peter Dracatos, breeding researcher and junior professor at La Trobe University in Melbourne (previously at University of Sydney 2012-2021), for the past three years. Fellows are allowed to choose the foreign partner institutions with which they wish to cooperate. Receiving a fellowship is both: an award for the fellow's research and an honor for the host institution.
Gene pool characterization and rust resistance evaluation of barley
Peter Dracatos was due to arrive at Quedlinburg in July 2021, but the coronavirus pandemic intervened. Since November 1, the Humboldt Fellow finally has been sharing an office with JKI host and colleague Dr. Dragan Perovic. The Australian breeding researcher is looking for new mechanisms of disease resistance in both - wild and cultivated - barley crop accessions.
"Barley is becoming an increasingly interesting crop due to climate change, as it still achieves good yields even in poor locations. But foliar diseases such as rust or mildew continue to threaten the crop's harvest and grain quality. Resistant barley plants provide a sustainable resource for controlling pathogens and protecting yield," said Dr. Peter Dracatos.
In order to introduce disease resistance into new varieties, the genetic pool has to be characterized and fundamental genetic mechanisms understood. This is why Dracatos is not working exclusively with the JKI during his research stay: The proximity to the IPK Gatersleben and its gene bank collection is a crucial advantage for the Australian's research project. In 2016, the breeding researcher selected and propagated 465 barley genotypes of Eastern Europe originating from the IPK gene bank, which he transferred to the Australian gene bank. In order to identify new resistance genes for barley breeding, Dracatos now wants to infect these genotypes with rust fungus isolates from the JKI. These fungus strains do not occur in Australia yet.
As Australian Grain Industry gave him a grant to purchase a high-throughput phenotyping system (Macrobot) for further breeding research, he also uses his stay to get familiar with the handling of the Macrobot located at the Institute for Resistance Research and Stress Tolerance.
Tool mutational genomics - Czech Republic and Germany provide support
The breeding researcher uses mutational genomics to quickly isolate possible resistance genes. In other words, he causes mutations in a barley variety with the desired resistance gene and subsequently screens the progeny for loss of resistance. For this purpose, only the coding part of the genome (exon) is sequenced (e.g. MutRenSeq). If several disease-susceptible offspring with mutations in the same gene are obtained, this provides strong evidence that the gene in question is responsible for resistance. Here, Dracatos benefits from Dr. Perovic's work, who recently optimized the MutRenSeq protocol.
Another part of the gene isolation will take place in the Czech Republic, at the Institute for Experimental Botany, with Prof. Jaroslav Dolezel. His working group is contributing its expertise in sorting and sequencing chromosomes using flow cytometry.
Source: julius-kuehn.de