Fig. 8

Effects of ‘Ca. L. asiaticus’ infection and D. citri infestation on the endogenous GABA content and its transport carrier CsgabP from Valencia sweet orange (Citrus sinensis). (A and B) Effect of ‘Ca. L. asiaticus’ infection and/or GABA supplementation on endogenous GABA levels (µg.g^− 1 FW) and CsgabP relative gene expression from Valencia sweet orange, respectively. (C,D, and E) Simple linear regression (SLR) analysis between endogenous GABA levels (µg.g^− 1 FW) and CsgabP relative gene expression from healthy, Ca. L. asiaticus’-infected, and ‘Ca. L. asiaticus’-infected + GABA (10 mM) Valencia sweet orange, respectively. (F and G) Effect of D. citri infestation and/or GABA supplementation on endogenous GABA levels (µg.g^− 1 FW) and CsgabP relative gene expression from Valencia sweet orange, respectively. (H,I, and J) Simple linear regression (SLR) analysis between endogenous GABA levels (µg.g^− 1 FW) and CsgabP relative gene expression from healthy, D. citri-infested, and D. citri-infested + GABA (10 mM) Valencia sweet orange, respectively. In boxplots, whiskers represent the minimum and the maximum values, while thick horizontal lines specify the median. Light-blue boxes show the interquartile ranges (25th to 75th percentile of the data), white dots represent the raw data (n = 6), and gray shading represents the corresponding violin plot. Different letters signify statistically significant differences among treatments, whereas the same letters indicate no significant differences among them using Tukey’s HSD (p < 0.05). In SLR models, blue dots represent raw data (n = 6). The fitted SLR line is presented as blue lines. The 95% confidence intervals for the estimated regression are shaded with the same color and edged by dotted lines. Regression equations for both SLR and SPR models, R²and p-value based on the F test (p ≤ 0.05) were also obtained and are presented within the graphs.