Quantitative PCR (qRT-PCR) analysis of sucrose and glucose responsive genes. The y axis refers to the relative expression ratio between target mRNA versus the reference mRNA (tubulin SCCCRZ1002H03.g) for 3 different experiments in sugarcane thirteen-old day seedlings treated with 3% glucose and 3% sucrose for 4 h. R1, R2 and R3 refers to three control and three sucrose and glucose independent treatments. Error bars were calculated as described previously . The transcript levels for the reference genes were verified to not vary in response to the treatments. The values of P correspond to the probability Pr (Treated>Control) and Pr (Treated<Control) for up- and down-regulated genes, respectively. The SAS was considered differentially expressed when P ≥ 0.95.