Mapping of a Stripe Rust Resistance Gene Yr72 in the Common Wheat Landraces AUS27506 and AUS27894 from the Watkins Collection

Mumta Chhetri; Hanif Miah; Debbie Wong; Matthew Hayden; Urmil Bansal; Harbans Bariana

doi:10.3390/genes14111993

Mapping of a Stripe Rust Resistance Gene Yr72 in the Common Wheat Landraces AUS27506 and AUS27894 from the Watkins Collection

Genes (Basel). 2023 Oct 25;14(11):1993. doi: 10.3390/genes14111993.

Authors

Mumta Chhetri¹, Hanif Miah¹, Debbie Wong², Matthew Hayden², Urmil Bansal¹, Harbans Bariana^{1

3}

Affiliations

¹ Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, 107 Cobbitty Road, Cobbitty, NSW 2570, Australia.
² AgriBioCentre, Department of Environment and Primary Industries, La Trobe Research and Development Park, Bundoora, VIC 3082, Australia.
³ School of Science, Western Sydney University, Bourke Road, Richmond, NSW 2753, Australia.

Abstract

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is among the major threats to global wheat production. The common wheat landraces AUS27506 and AUS27894 displayed stripe rust resistance against several commercially prevailing Pst pathotypes. These genotypes were crossed with a stripe-rust-susceptible landrace AUS27229 to understand the inheritance of resistance and to determine the genomic location(s) of underlying gene(s). F₃ generations of crosses AUS27506/AUS27229 and AUS27894/AUS27229 showed monogenic segregation for stripe rust resistance under greenhouse conditions. The absence of segregation for stripe rust response among the AUS27506/AUS27894-derived F₃ population suggested that both genotypes carry the same gene. The stripe rust resistance gene carried by AUS27506 and AUS27894 was tentatively named YrAW4. A bulked segregant analysis placed YrAW4 in the long arm of chromosome 2B. The AUS27506/AUS27229 F₃ population was enhanced to develop an F₆ recombinant inbred line (RIL) population for detailed mapping of chromosome 2BL. DArT-based SSR, STS and SNP markers were employed to enrich the 2BL map. DArT-based STS markers sun481 and SNP marker IWB12294 flanked YrAW4 proximally (1.8 cM) and distally (1.2 cM), respectively. Deletion mapping placed sun481 in the deletion bin 2BL-5. All stripe rust resistance genes, previously located on chromosome 2BL, neither express an infection type like YrAW4, nor are they mapped in the deletion bin 2BL-5. Hence, YrAW4 represented a new locus and was formally named Yr72. The usefulness of the markers IWB12294 and sun481 in marker-assisted selection was demonstrated by the amplification of alleles that are different to that linked with Yr72 in 19 common wheat and two durum wheat cultivars.

Keywords: KASP marker; STS marker; marker validation; stripe rust; wheat.

MeSH terms

Alleles
Basidiomycota* / genetics
Chromosome Mapping
Genetic Markers
Genotype
Triticum* / genetics

Substances

Genetic Markers

Grants and funding

Financial support from the Australian Government via the Department of Foreign Affairs and Trade’s Australia Awards Fellowship Program, University of Sydney (for research facilities), and the Grains Research and Development Corporation (GRDC) Australia (for salaries of supervisors) is gratefully acknowledged.