Fig. 4

The effect of different quantities of NPK fertilizer and PGPR bacteria on chlorophyll and carotenoid of cucumber leaves in the productive phase. A Variation of Chla content of inoculated cucumber leaves. B Variation of Chlb content of inoculated cucumber leaves. C Variation of total Chl content of inoculated cucumber leaves. D Variation of carotenoid content of inoculated cucumber leaves. Different level of NPK fertilizers is a1 (50% = 1 g/L) a2 (75% = 1.5 g/L) and a3 (100% = 2 g/L) based on recommended amount of different growth level of cucumber (vegetative growth, flowering, and fruiting). 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)