Construction of a rye cv. Blanco BAC library, and progress towards cloning the rye Alt3 aluminium [aluminum] tolerance gene

Abstract

In addition to being an important cereal crop, rye (Secale cereale L.) provides valuable traits for other crops, as a parent of the amphidiploid triticale, and as a donor of translocated chromosome segments in wheat. Rye possesses excellent tolerance to many biotic and abiotic stresses that could potentially be transferred to wheat, and as a genetic system benefits from being highly variable, diploid and closely related to the more extensively characterized species wheat and barley. To provide a resource to assist the characterization and isolation of genes and gene complexes from rye, a large-insert genomic (BAC) library of rye cv. Blanco has been constructed, which to our knowledge, is the first such library made of this species. The library is comprised of 373,632 clones with an average insert size of 130 kb, representing a little over a 6-fold coverage of the 8,110 Mbp genome. Copies of the library will be kept at the University of Missouri, the Australian Centre of Plant Functional Genomics (Adelaide), and IPK Gatersleben, and will be available to researchers for unrestricted use. Of all the cultivated cereals, rye is the most tolerant to aluminum toxicity in acid soils, a stress that is a serious constraint to cereal cultivation worldwide. We have mapped the A1 tolerance locus Alt3 in rye to high resolution using gene co-linearity with rice. Progress towards cloning and characterization of this gene using the Blanco BAC library and other resources will be presented. This rye BAC library will have a significant impact on the world's ability to analyze the rye genome and in gene cloning in the rye genus.