Locating two novel genes for resistance to powdery mildew from Avena byzantina in the oat genome

Abstract

Powdery mildew of oats is a major threat to intensive oat farming under humid climate, and the use of resistant cultivars is the most environmentally friendly way of achieving safe yields. In this study, the genetic mapping of unexplored resistance genes from Avena byzantina accessions AVE2406 and AVE2925, designated Pm9 and Pm10, is described. Both accessions were crossed with susceptible cultivars, and monogenic segregation was established based on detached leaf segment tests.The two recombinant inbred line (RIL) populations RIL29 (with AVE2925) and RIL24 (with AVE2406) were phenotyped for powdery mildew resistance and genotyped with DArTseq. The genetic map of RIL24 had 2,516 markers in 30 linkage groups with a length of 2,641.5 cM; for RIL29, 921 markers were allocated to 30 linkage groups totalling to 1,378.2 cM. A major resistance QTL in RIL24 harbouring Pm9 was mapped to Mrg21 of the consensus map using BLASTn analysis. For RIL29, a QTL was found on Mrg03. The results support that at least Pm9 is different from the powdery mildew resistance genes mapped so far.

Allocation of the oat powdery mildew resistance gene Pm3 to oat chromosome 1A

“…For the diversity panel, genomic DNA was extracted from lyophilized primary wheat leaves as described by Plaschke et al (1995). For 53 oats of the collection, the Pm3 and other Pm phenotypes were known from previous studies (Hsam et al 1997(Hsam et al , 2014Yu and Herrmann 2006;Herrmann and Mohler 2018). The pedigrees of the oat lines carrying Pm3 (Table S2) were accessed from the POOL database (Tinker and Deyl 2005; https:// triti ceaet oolbox.…”

“…Eleven major genes for resistance to powdery mildew in cultivated oats have been catalogued so far (Pm1-Pm11; Hsam et al 2014;Herrmann and Mohler 2018;Ociepa et al 2020), but many more sources, as yet uncharacterized, for resistance to powdery mildew do exist in oat landraces and wild relatives of different ploidy levels (Herrmann and Roderick 1996;Okoń et al 2014Okoń et al , 2016Okoń et al , 2018Okoń and Kowalczyk 2020). Although the access to genes from lower ploidy levels for enhancing cultivated oat germplasm is challenging (e.g., Aung et al 1977Aung et al , 2010Thomas et al 1980), agriculture will finally benefit from this work.…”

“…Of the 11 documented powdery mildew resistance genes, Pm9, Pm10, and Pm11 were allocated to the oat consensus map by GBS marker sequence information (Herrmann and Mohler 2018;Ociepa et al 2020). It is expected that further consensus map-based genetic mapping studies, e.g., crown rust resistance gene Pc39 was allocated to Mrg11 (Sowa and Paczos-Gręda 2020;Zhao et al 2020a), Pc53 to Mrg08 (Admassu-Yimer et al 2018, and Pc98 to Mrg20 (Zhao et al 2020b), will facilitate determining how resistance genes are distributed across the oat genome.…”

Is Every Wild Species a Rich Source of Disease Resistance? Avena fatua L.—Potential Donor of Resistance to Powdery Mildew

“…So far, 11 resistance genes to powdery mildew have been identified in oat. These genes were introduced into the cultivars from A. sterilis L. ( Pm1, Pm3, Pm8 and Pm11 ), A. byzantina L. ( Pm6, Pm9, Pm10) A. hirula L. ( Pm2 ), A. barbata L. ( Pm4 ), A. macrostachya L. ( Pm5 ) and A. eriantha L. ( Pm7 ) [ 5 , 42 , 43 , 44 , 45 , 46 ]. However, none of the described resistance genes are derived from A. fatua ; therefore, in the present study we attempted to determine whether A. fatua could be used as a source of effective resistance genes against powdery mildew in oat.…”

Virulence Structure of Blumeria graminis f. sp. avenae Populations in Poland across 2014-2015

“…The introduction of crop cultivars that contain effective resistance genes is the most effective and environmentally friendly method of infection control ( Okoń et al, 2016 ). To date, 11 powdery mildew resistance genes have been identified and characterized in oat ( Herrmann and Mohler, 2018 ; Hsam et al, 2014 ; Ociepa et al, 2020 ). The relationship between the host and powdery mildew is closely related to the “gene-for-gene” hypothesis, which says that a virulence gene ( Avr ) in the pathogen’s genome is directed against a resistance ( R ) gene in the plant ( Flor, 1971 ; Heath, 2000 ; Okoń and Ociepa, 2017 ).…”