Expression data from malting barley seeds

Malting is seed germination under strictly controlled environmental conditions. Malting quality is a complex phenotype that combines a large number of interrelated components, each of which shows complex inheritance. Currently, only a few genes involved in determining malting quality have been characterized. This study combined transcript profiling with phenotypic correlations to identify candidate genes for malting quality. We used the Barley1 GeneChip® array to identify differentially expressed genes in four malting stages relative to dry seed in the barley variety Morex, and to identify differentially expressed genes among four barley varieties. Keywords: time course and genotype differences Four malting barley cultivars were micromalted: Morex and Legacy (6-row), Merit and Harrington (2-row). Two to three batches of micromalting (biological replications) were performed. For each micromalting experiment, 20 g samples were collected for Morex at four stages: steeping, 24 h germination (day 1), 93 h germination (day 4), and finished malt after kilning was completed. Ungerminated, dry seed of Morex was used as reference sample. In another experiment, seeds of Legacy, Harrington, and Merit were micromalted and 20 g samples were collected for each variety during day 1 and day 4 germination stages. Expression profiles were compared among the four cultivars separately for day 1 and day 4.