Genomics as a tool for cereal chemistry

Genomics is providing a new set of tools for cereal chemistry. Analysis of the DNA of the major cereals is increasing the understanding of the basis of grain quality at the gene level. Differences in the sequence of the gene in different cultivars or differences in the level of expression of the gene may be used to explain differences in processing or end-use quality characteristics. For example, quantitative analysis of the levels of expression of genes at different stages during seed development in wheat or germination in barley can be used to define the genetic basis of differences in wheat and barley quality. Rice quality traits such as fragrance and gelatinization temperature (cooking temperature) can be explained by DNA sequence differences in specific genes identified using genomics approaches. Rapid and reliable species and cultivar identification based on DNA analysis methods developed using genomics tools can be applied to grain and to food products. This technology has special advantages in the analysis of complex mixtures of cereals. Technologies for very high-throughput and very low-cost analysis of large numbers of samples are now available. These may be applied by cereal chemists at many levels: selection in cereal breeding, optimizing processing, and analysis of the identity and composition of grain or food samples.