Multiplexed high-throughput barley variety identification

Correct identification of varieties is vital for quality assurance in barley production and use. Malting characteristics are variety dependent thus sourcing the correct variety is vital to product consistency. Identification using morphological and physiological characters is still widely used, however these characters can be influenced by environmental conditions and the techniques can be time-consuming. Fast and reliable identification requires a stable marker that is not influenced by environment, and a platform which is capable of high throughput genotyping. In order to facilitate rapid, high throughput identification of barley varieties, we have developed a multiplexed assay capable of determining variety identity with precision and speed. A comprehensive collection of Australian barley germplasm was collected and genome-wide polymorphic molecular markers (SNPs) were identified from EST databases. We used MALDI-TOF mass spectrometry to identify the SNPs by determining the mass of the polymorphic nucleotide itself. Genotype calling was precise and a unique SNP barcode was produced for each variety. Coupled with the ability to multiplex up to 25 reactions per well on a 384-well plate in a fully automated process, MALDI-TOF mass spectrometry SNP genotyping clearly has the potential to be a high-throughput barley variety identification method of choice.