The MdGMP1 mRNA level is related to the MdERF98 transcript level in MdAMR1L1 overexpression transgenic lines. A, Relative expression levels of MdERF98 mRNA in leaves of WT, WT-i98, 1OL-2 and 5, and 1OL-2/5-i98 lines based on qRT-PCR. For each sample, transcript levels were normalized with those of MdActin. Relative expression levels for each gene were obtained via the ΔΔCT method. The value of WT-Vector was set to “1”. MdERF98 expression was silenced in “GL3” leaves of WT and MdAMR1L1-OE (1OL-2 and 1OL-5) transgenic lines. WT-i98, MdERF98 RNAi silencing in WT background; 1OL-2/5-i98, MdERF98 RNAi silencing in MdAMR1L1 overexpression backgrounds. B and C, Relative expression levels of MdGMP1 and MdGME1 transcripts in leaves of WT, WT-i98, 1OL-2/5, and 1OL-2/5-i98 lines based on qRT-PCR. For each sample, transcript levels were normalized with those of MdActin. Relative expression levels for each gene were obtained via the ΔΔCT method. The value of WT-Vector was set to “1”. D, Levels of Asc in leaves of WT, WT-i98, 1OL-2/5, and 1OL-2/5-i98 lines. Bars represent the mean value ±se (n = 3). Lowercase letters/asterisks indicate significantly different values (P < 0.05, one-way ANOVA test or independent t tests).