Figure 4.

Expression analysis of genes involved in starch and sugar metabolism. Normalized RNA‐seq data was used to generate heat maps for nectary‐expressed genes involved in starch synthesis (a), starch degradation (b), and sucrose biosynthesis (c). The fold‐change in each stage was determined relative to 0 hr (the secretory stage [anthesis] was set as 1). In general, starch biosynthesis genes peak at −24 hr, starch degradation genes peak at −15 hr (with the exception of BAM1), and sucrose biosynthesis genes are highest at −15 and 0 hr. This analysis supports a progression of starch synthesis, starch degradation, and sucrose biosynthesis as being essential for nectary function. Full names for the abbreviations of individual genes are provided in Appendix S10