Figure 2.

MdAMR1L silencing increased Asc levels and MdGMP1 protein level in apple flesh. A, Relative expression levels of MdAMR1L1 (black) and MdAMR1L2 (gray) in “Starking Delicious” flesh inside the injection area 6 d after VIGS treatments 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. Fruit inoculated with Agrobacterium tumefaciens containing empty vectors (pTRV2) and without injection (untreated) were taken as the controls. B, Levels of total Asc (T-Asc, black) and reduced Asc (Asc, grey) in ‘Starking Delicious’ flesh 6 d after VIGS treatments. C, Expression abundances of MdAMR1L1/2 and MdGMP1 proteins in ‘Starking Delicious’ flesh inside the injection areas 6 d after VIGS treatments. β-Actin was used as the reference protein. Untreated was not injected with any treatment. D, Asc localization using AgNO₃ in transverse sections of ‘Starking Delicious’ flesh after silencing MdAMR1L1/2 (pTRV2-MdAMR1L1/2) for 6 d. The image was digitally extracted. Injection areas are marked. Bars represent the mean value ±se (n = 3). Asterisks indicate significantly different values (P < 0.05, independent t tests).