Skip to main content
Research article - Peer-reviewed, 2020

Multiplex qPCR assay for simultaneous quantification of CYP51-S524T and SdhC-H152R substitutions in European populations ofZymoseptoria tritici

Hellin, Pierre; Duvivier, Maxime; Clinckemaillie, Aurelie; Bataille, Charlotte; Legreve, Anne; Heick, Thies M.; Jorgensen, Lise N.; Andersson, Bjorn; Samils, Berit; Rodemann, Bernd; Berg, Gunilla; Kildea, Steven


Demethylation inhibitor (DMI) and succinate dehydrogenase inhibitor (SDHI) fungicides are currently relied upon for the control of septoria tritici blotch (STB) in European wheat fields. However, multiple mutations have occurred over time in the genes encoding the targeted proteins that have led to a practical loss of fungicide efficacies. Among the different amino acid substitutions inZymoseptoria triticiassociated with resistance to these fungicides, S524T in CYP51 (DMI target) and H152R in SdhC (SDHI target) are regarded as conferring the highest resistance factors to DMI and SDHI, respectively. To facilitate further studies on the monitoring and selection of these substitutions inZ.triticipopulations, a multiplex allele-specific quantitative PCR (qPCR) assay allowing for estimation of both allele frequencies in bulk DNA matrices was developed. The assay was then used on complex DNA samples originating from a spore trap network set up in Belgium, Denmark, Sweden, and Ireland in 2017 and 2018, as well as on leaf samples with symptoms. The S524T allele was present in all field samples and its proportion was significantly higher in Ireland than in Belgium, whereas the proportion of H152R was only sporadically present in both countries. The frequency of S524T varied greatly in the airborne inoculum of all four countries; however, the H152R allele was never detected in the airborne inoculum. The method developed in this study can be readily adopted by other laboratories and used for multiple applications including resistance monitoring in field populations ofZ.tritici.


airborne inoculum; Mycosphaerella graminicola; SDHI; septoria tritici blotch; triazole; wheat

Published in

Plant Pathology
2020, volume: 69, number: 9, pages: 1666-1677
Publisher: WILEY

Authors' information

Hellin, Pierre
Universite Catholique Louvain
Duvivier, Maxime
Walloon Agricultural Research Centre
Clinckemaillie, Aurélie
Walloon Agricultural Research Centre
Bataille, Charlotte
Walloon Agricultural Research Centre
Legreve, Anne
Universite Catholique Louvain
Heick, Thies M.
Aarhus University
Jorgensen, Lise N.
Aarhus University
Swedish University of Agricultural Sciences, Department of Forest Mycology and Plant Pathology
Rodemann, Bernd
Julius Kuhn-Institut
Berg, Gunilla
Swedish Board of Agriculture
Kildea, Steven
Swedish University of Agricultural Sciences, Department of Forest Mycology and Plant Pathology

Associated SLU-program

SLU Network Plant Protection

UKÄ Subject classification

Agricultural Science

Publication Identifiers


URI (permanent link to this page)