|O'LEARY-JEPSEN, E - Idaho State University|
Submitted to: Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/17/2010
Publication Date: 5/21/2010
Citation: Oliver, R.E., Obert, D.E., Hu, G., Bonman, J.M., O'Leary-Jepsen, E., Jackson, E.W. 2010. Development of oat-based markers from barley and wheat microsatellites. Genome. 53(6): 458–471.
Interpretive Summary: Oat contains high levels of dietary fiber and antioxidants, which are known to aid in prevention of coronary heart disease and other serious and common health risks. Use of molecular markers could facilitate selection and introgression of these traits into cultivated oat, allowing enhanced levels of multiple important quality traits to be simultaneously combined into a single variety. However, since the oat genome is large and complex, marker resources are limited. We evaluated molecular markers derived from wheat and barley and developed new, oat-based markers. These markers may help to facilitate marker-assisted breeding for key nutritional and agronomic traits, and also provide information on possible chromosome relationships in the complicated oat genome.
Technical Abstract: Although microsatellites are an efficient and reliable genetic marker system, availability is limited in cultivated oat (Avena sativa L.). Previous research has suggested that microsatellites from related species may be adapted to oat. This study investigated stability of existing oat microsatellites, sequenced polymorphic oat amplicons derived from wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) primers, and redesigned primers to develop oat-based markers. We evaluated 161 published oat microsatellites and identified 9 with polymorphism between mapping parents Ogle1040 and TAM O-301 (OT). We also studied 30 wheat, one Aegilops tauschii Coss., and nine barley primers with reported oat polymorphism. Sixteen primers (one A. tauschii, ten wheat, five barley) amplified random oat sequences and were used to generate 28 new oat STS markers. Eight primers, four each from wheat and barley, amplified oat repetitive motifs, generating 10 new oat SSRs. Four additional SSRs were developed from characterization of thaumatin-like pathogenesis-related protein sequences, formerly utilized as the Rast1-4 oat marker. These 48 new markers, along with nine existing oat SSRs and six previously-identified disease resistance loci, were mapped in the OT population, joining three pairs of linkage groups. Map locations of multiallelic SSRs and disease-resistance QTL interactions suggested possible homoeologous relationships among the oat chromosomes.