Changes in β-amylase activity during early germination of wheat seeds. (a) The first group treated with sterile water under different treatments including X1, X2, X3, and X4, which represent the control group (sterile water, X1), 107 CFU/mL B. subtilis QM3 (X2), 106 CFU/mL B. subtilis QM3 (X3), and SNP (X4), respectively. (b) The second group treated with α-cyclodextrin under different treatments including Y1, Y2, Y3, and Y4, which represent the control group (sterile water, Y1), 107 CFU/mL B. subtilis QM3 (Y2), 106 CFU/mL B. subtilis QM3 (Y3), and SNP (Y4), respectively. Different lowercase letters represent a significant difference between the treatment 1, 2, 3, and 4 under the same time (P < 0.05).