Figure 2.

Heterologous expression of AtBBX21 promotes stem vasculature and leaf thickening in potato plants. A, Cross section of apex, middle, and basal stems of nontransformed (Spunta) and transgenic plants (CH2). B, Layer number of parenchymal cells (n = 3). C, Leaf lamina width (n = 3). p, Parenchyma; v, vascular bundle; pm, palisade mesophyll cell; sm, spongy mesophyll cells. Bar = 50 µm. n = technical replicates for each genotype. Mean values are shown with error bars indicating se. Asterisks indicate significant difference between nontransformed and transgenic lines (**P < 0.01 and ***P < 0.001).