Fig. 4

Effects of biofertilizers on the activities of SPS (a), SuSy (c), AI (e); relative expression level of GmSPS1(b); GmSuSy (d) and GmC-INV (f) of soybean under drought stress condition. Means sharing the same letters, for a parameter during a year, do not differ significantly at α = 0.05 after Student–Newman–Keul test. Ck (complete irrigation); D1 (withholding irrigation at R3 stage) and D2 (withholding irrigation at R5 stage)