Fig. 5

Mean comparison for effect of different NPK fertilizer quantities and PGPR bacteria on macro elements and soluble carbohydrates of fruit cucumber. A Variation of potassium content of inoculated cucumber fruit. B Variation of phosphate content of inoculated cucumber fruit. C Variation of nitrate content of inoculated cucumber fruit. D Variation of glucose content of inoculated cucumber fruit. E Variation of sucrose content of inoculated cucumber fruit. F Variation of fructose content of inoculated cucumber fruit. Different levels of NPK fertilizers are a1 (50% = 1 g/L) a2 (75% = 1.5 g/L) and a3 (100% = 2 g/L) every week based on recommended amount of different growth levels of cucumber (vegetative growth, flowering, and fruiting). In each NPK fertilizer level, a treatment co-cultivated by sand was used as a control. Values represent means of three replicates; bars represent standard deviation of the three replicates. Different letters within columns indicate significant differences according to Duncan’s Multiple Range Test (P ≤ 0.05)