Sequencing the Sorghum Genome
We also participated in a consortium to sequence the sorghum genome. The sequenced cultivar was BTx623, which is grain sorghum. Grain sorghum like maize is used as animal feed, but it can grow on marginal land and uses less water and fertilizer than maize. Another type of sorghum is called sweet sorghum because it accumulates like sugarcane soluble sugars in the stem. Sweet sorghum provides an alternative to sugarcane, which is a close relative, as a biofuel crops because of its preferable traits, a simple diploid genome, and standard genetic system, whereas sugarcane has an allopolyploid genome and requires a long time for standard breeding. We therefore have investigated which differentially expressed genes are linked to the stem-sweetness phenotype of sorghum. To understand the regulation of those differentially expressed genes, we have investigated the small RNA transcriptome in the F2 of crosses between grain and sweet sorghum and their parents.