Mining the global diversity of barley for Fusarium resistance using leaf and spike inoculations
Fusarium graminearum is a devastating fungal pathogen that causes
significant yield and quality losses in cereals. We utilized a diversity
set of barley (140 genotypes) to explore vital resistance alleles against
this aggressive pathogen. The resistance assessment was carried out on
spikes and leaves via artificial inoculations under control conditions.
The phenotypic data was subjected to genome-wide association
analysis using a genetic map based on DArT and SNP markers. This
analysis revealed eleven and nine marker trait associations for leaf
disease scoring (LDS) and spike disease scoring (SDS), respectively.
The strongest QTL for LDS was found on chromosome 1H where a
minor allele of wild origin decreased disease symptoms by 78%. The
major QTL allele for SDS was linked with marker locus
SCRI_RS174710 on chromosome 5H. In addition, four favorable
epistatic interactions effects were found in decreasing disease
symptoms. Overall, three QTL were common for LDS and SDS, which
indicates a partial genetic relatedness of these resistances in barley. The
QTL alleles for LDS and SDS will help to establish organ specific
resistances in cultivated barley.