Fig. 6

Functional enrichment analysis of differentially expressed genes in low-sugar (LS) sugarcane before and after ethylene treatment. a The up-regulated functions are displayed with respect to their significance (p < 0.01). Different colors correspond to the ratio of genes in each category. It’s noteworthy that the most enriched function is RNA-related transcription (corresponding to ethylene response factor; ERFs) and hormone-related metabolism and signaling (ethylene-related). These enriched modules will guid the search for the functional networks underpinning ethylene-regulated sugar production/translocation in sugarcane. b the expression of ERFs in HS and LS following ethylene treatment. CK- check (water control), T- ethephon treatment, HS: high-sugar variety, MS: medium-sugar variety, LS: low-sugar variety