Expression of COE genes in B. tabaci MED adults treated with an imidacloprid gradient. A total of 14 COE amino acid sequences of B. tabaci MED were aligned by MUSCLE, and the phylogenetic tree was constructed by MEGA 6.0 using the NJ method based on the JTT model with a uniform substitution rate. Bootstrap values displayed at branch points are expressed as percentages of 1000 replicates. The color scale is displayed on the right side; yellow represents higher expression values (log2-transformed FPKM values), while blue represents lower expression values (log2-transformed FPKM values). IM0, whitefly treated with water; IM25, whitefly treated with 25 mg/L imidacloprid; IM50, whitefly treated with 50 mg/L imidacloprid; IM100, whitefly treated with 100 mg/L imidacloprid.