Genes required for sucrose biosynthesis are upregulated in nectaries. Genes involved in sucrose biosynthesis, export, and hydrolysis were examined for differential expression between mature lateral nectaries and reference tissues. Individual upregulated genes are labeled within the sucrose biosynthetic pathway (left panel), and the average probe signal value ratio between MLN and reference tissues is shown in parentheses. Most of these genes were significantly upregulated in nectaries over all individual reference tissues, with the heat map (right panel) indicating the relative differences in the probe signal value ratio. The sucrose biosynthetic pathway presented was based on that found in the Plant Metabolic Network (PMN) .