Fig. 8
From: MdFRK2-mediated sugar metabolism accelerates cellulose accumulation in apple and poplar
Secondary phloem of the transgenic poplar lines (OE#1, OE#4 and OE#9) overexpressing MdFRK2. a–d Cellulose (green color) in stem sections stained with safranin and fast green. Scale bars = 200 μm. a Wild type (WT, Populus clone 717); b: transgenic line OE#1; c: transgenic line OE#4; d: transgenic line OE#9. ph: phloem (black arrow); xy: xylem (black arrow); C: cambium (black arrow); red lines: the cambium and secondary phloem region. An increase in thickness e and area f of the secondary phloem region in transgenic lines (OE#1, OE#4 and OE#9) in comparison with WT. Bars represent the mean value ± SE (n ≥ 3). The asterisk indicates a significant difference at P ≤ 0.05