Fig. 2
The root resistance indexes of two soybean germplasms were measured under four different treatments. The soybeans were cultured to the V2 growth stage before being transferred to hydroponic cultures that mimicked CK (control), LP (50 µM H3PO4), S (200 mM NaCl), and LPS (50 µM H3PO4 and 200 mM NaCl) conditions for 24 and 48 h. The levels of TSP content (A), ACP activity (B), SOD activity (C), and POD activity (D) in roots were measured. Different letters above columns of different colors indicate statistically significant differences at P < 0.05 (Duncan’s multiple range test). The * (P < 0.05) and ** (P < 0.01) indicate significant differences between bars of the same color (Student’s t-test). CK represents control, LP represents low phosphorus, S represents salt and LPS represents low phosphorus + salt