Molecular identification and chromosomal localization of new powdery mildew resistance gene Pm11 in oat

Abstract

The appropriate selection of various traits in valuable plants is very important for modern plant breeding. Effective resistance to fungal diseases, such as powdery mildew, is an example of such a trait in oats. Marker-assisted selection is an important tool that reduces the time and cost of selection. The aims of the present study were the identification of dominant DArTseq markers associated with a new resistance gene, annotated as Pm11 and derived from Avena sterilis genotype CN113536, and the subsequent conversion of these markers into a PCR-based assay. Among the obtained 30,620 silicoDArT markers, 202 markers were highly associated with resistance in the analysed population. Of these, 71 were selected for potential conversion: 42 specific to resistant and 29 to susceptible individuals. Finally, 40 silicoDArT markers were suitable for primer design. From this pool, five markers, 3 for resistant and 2 for susceptible plants, were selected for product amplification in the expected groups. The developed method, based on 2 selection markers, provides certain identification of resistant and susceptible homozygotes. Also, the use of these markers allowed the determination of heterozygotes in the analysed population. Selected silicoDArT markers were also used for chromosomal localization of new resistance genes. Five out of 71 segregating silicoDArT markers for the Pm11 gene were found on the available consensus genetic map of oat. Five markers were placed on linkage groups corresponding to Mrg12 on the Avena sativa consensus map.

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

“…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.…”

Genome-wide identification of the oatMLOfamily and identification of a candidateAsMLOassociated with powdery mildew susceptibility

“…Currently, the most sustainable method of controlling Bga in oats is the use of resistant cultivars (Okoń, 2015). However, only 11 resistance genes have been catalogued in oats (Ociepa et al , 2020), and the effectiveness of these R- genes may break down over time with the emergence of new virulent isolates of the pathogen (Várallyay, et al , 2012). As a result, there is a need to identify more durable forms of resistance.…”