A universal protocol for identification of cereals

Plant fingerprinting and identification has increasingly become a focus in commerce and manufacturing with an emphasis on fast, reliable and cost effective high throughput techniques. GBSS1 is a well conserved single copy nuclear gene in the grass family with potential for generating a universal approach to grass fingerprinting. Alignment of DNA sequences from Poaceae members identified five well conserved regions. PCR primers designed to these regions amplified single DNA fragments on all grasses tested. DNA sequencing revealed polymorphism within these DNA fragments allowing identification at the species level. A universal sequencing primer for Poaceae enabled pyrosequencing through a 28 base pair highly polymorphic region generating unique pyrograms for rice, wheat, barley and maize. Analysis of exon/intron composition including intron length and number, of GBSS1 provided another distinct fingerprinting method for grasses. Phylogenetic utility of these fragments was demonstrated by production of phylograms consistent with previously described taxonomic relationships for the Poaceae family. The sequence polymorphism of the GBSS1 gene provides the basis for universal primer design for identification of members of the Poaceae family. The protocols developed may prove more generally useful in the distinction of plant species in other plant families.