Abstract

Oat stem rust, caused by Puccinia graminis f. sp. avenae (Pga), is one of the most severe diseases of oats worldwide. Population studies are scarce for this pathogen, mainly due to the lack of polymorphic molecular markers suitable for genetic analysis. In this study, an Australian Pga isolate was sequenced, the abundance of simple sequence repeats (SSRs) was determined and PCR-based polymorphic markers suitable for genetic diversity analysis were developed. The amplification of 194 primer pairs was initially assessed using a set of 12 isolates of different cereal rust species and their formae speciales. A high frequency of cross-species amplification was observed for most markers; however, 36 SSRs were diagnostic for P.graminis only. A subset of 19 genome-derived SSRs were deemed useful for genetic diversity analysis of Pga and were assessed on 66 Pga isolates from Australia, Brazil and Sweden. Brazilian and Australian isolates were characterized by one and two predominant clonal lineages, respectively. In contrast, the Swedish isolates, previously shown to undergo sexual recombination, were highly diverse (nine distinct genotypes out of 10 isolates) and divided into two subpopulations. The genome-derived SSR markers developed in this study were well suited to the population studies undertaken, and have diagnostic capabilities that should aid in the identification of unknown rust pathogen species.

Keywords

Avena sativa; microsatellite; population genetics; SSR transferability

Published in

Plant Pathology
2018, Volume: 67, number: 2, pages: 457-466

SLU Authors

• Berlin, Anna

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

UKÄ Subject classification

Other Agricultural Sciences not elsewhere specified
Ecology


Publication identifier

DOI: https://doi.org/10.1111/ppa.12742

Permanent link to this page (URI)

https://res.slu.se/id/publ/90893