Fig. 1

Histological analysis of three Zygophyllum species. Cross section analysis of the main stem of Zygophyllum brachypterum (a), Zygophyllum obliquum (b) and Zygophyllum fabago (c). Cross section analysis of the leaf of Zygophyllum brachypterum (d), Zygophyllum obliquum (e) and Zygophyllum fabago (f). Statistical analysis of the thickness of main stem xylem, phloem and cortex (g). Statistical analysis of the thickness of the main stem (h) and leaf (i). Scale bars = 0.2 mm in (a), (b) and (c). Scale bars = 0.1 mm in (d), (e) and (f). Values are the means ± SD from three replicates. Different letters indicate significant differences at P < 0.05 according to Duncan’s multiple range test