Isolate Specificity and Polygenic Inheritance of Resistance in Barley to the Heterologous Rust Pathogen Puccinia graminis f. sp avenae

Abstract

Barley is a near-nonhost to numerous heterologous (nonadapted) rust pathogens because a small proportion of genotypes are somewhat susceptible. We assessed 66 barley accessions and three mapping populations (Vada x SusPtrit, Cebada Capa x SusPtrit, and SusPtrit x Golden Promise) for response to three Swedish oat stem rust (Puccinia graminis f. sp. avenae) fungal isolates and determined that barley is a near-nonhost to P. graminis f. sp. avenae and that resistance was polygenically inherited. The parental genotypes Vada and Golden Promise were immune to all three isolates, whereas Cebada Capa was immune to two isolates and moderately resistant to the third. Phenotypic data from the Vada x SusPtrit mapping population and the barley accessions tested also demonstrated isolate-specific resistance. In particular, the SusPtrit parent and several other accessions allowed sporulation by isolate Ingeberga but were resistant to isolate Evertsholm. Nine chromosomal regions carried quantitative trait loci (QTL) (Rpgaql to Rpgaq9) of varying effect, most of which colocated to previously identified QTL for resistance to other heterologous rust pathogens. Rpgaql on chromosome 1H (Vada and Golden Promise) was effective toward all isolates tested. Microscopic examination indicated that resistance was prehaustorial in Vada whereas, in SusPtrit, both pre- and posthaustorial mechanisms play a role.

Published in

Phytopathology
2016, Volume: 106, number: 9, pages: 1029-1037

SLU Authors

• Berlin, Anna

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network


UKÄ Subject classification

Agricultural Science


Publication Identifiers

DOI: https://doi.org/10.1094/PHYTO-10-15-0264-R

Permanent link to this page (URI)

https://res.slu.se/id/publ/80847