Development of a set of PCR markers specific to Aegilops longissima chromosome arms and application in breeding a translocation line

Transcriptome data were used to develop 134 Aegilops longissima specific PCR markers and their comparative maps were constructed by contrasting with the homologous genes in the wheat B genome. Three wheat- Ae. longissima 1BL center dot 1S (l) S translocation lines were identified using the correspondence markers. Aegilops longissima is an important wild species of common wheat that harbors many genes that can be used to improve various traits of common wheat (Triticum aestivum L.). To efficiently transfer the traits conferred by these Ae. longissima genes into wheat, we sequenced the whole expression transcript of Ae. longissima. Using the transcriptome data, we developed 134 specific polymerase chain reaction markers located on the 14 chromosome arms of Ae. longissima. These novel molecular markers were assigned to specific chromosome locations based on a comparison with the homologous genes in the B genome of wheat. Annotation of these genes showed that most had functions related to metabolic processes, hydrolase activity, or catalytic activity. Additionally, we used these markers to identify three wheat-Ae. longissima 1BL center dot 1S(l)S translocation lines in somatic variation populations resulting from a cross between wheat cultivar Westonia and a wheat-Ae. longissima substitution line 1S(l)(1B). The translocation lines had several low molecular weight glutenin subunits encoding genes beneficial to flour processing quality that came from Ae. longissima 1S(l)S. The three translocation lines were also confirmed by genomic in situ hybridization. These translocation lines will be further evaluated for potential quality improvement of bread-making properties of wheat.