Genome-wide association study for net blotch adult plant resistance in European spring barley varieties from Polish Gene Bank

Barley is one of the economically important crop species and net blotch caused by Pyrenophora teres f. teres has a significant impact on the quantity and quality of grain yield. This disease occurs every year on barley in Central Europe including many areas of Poland.

The current study aimed to identify sources of resistance to barley net form of net blotch in the collection of 431 European barley accessions. They were evaluated phenotypically under field conditions scoring resistance to net blotch at heading and miky-waxy stages. Next, they were genotyped by Diversity Arrays Technology (DArT), a method utilizing Genotyping-By-Sequencing (GBS). Disease severity scored under field conditions was sufficient to differentiate the collection and to find marker-trait associations (MTAs) with resistance to the disease.

GWAS for net blotch resistance at the heading stage identified 10 marker-trait associations (MTAs) (2 on 1H, 2 on 3H, 2 on 5H, 2 on 6H, 1 on 7H, and 1 on Un). For net bloth resistance at the milky-waxy stage, 11 MTAs were identified (1 on 1H, 2 on 2H, 1 on 3H, 1 on 5H, 2 on 6H, 4 on 7H).

This preliminary work will be continued in the pre-breeding process. Next, these newly identified sources of resistance to net form of net blotch will be used by Polish breeders in barley breeding for resistance.