Figure 2
Attractiveness of the supercritical CO2 extracts of woods to Tribolium confusum in pitfall-trap olfactometer tests. A disk impregnated with 100 μl of acetone solution of each sample was placed in each of the two treatment traps, whereas a disk impregnated with only 100 μl acetone was placed in each of the two control traps (50 adult beetles starved for 24 h per replication). The total number of beetles in the two treatment traps was compared with the two control traps 3 h after the start of the assay. RI = 100 × (nt − nc)/tot, where nt, nc, and tot represent the total number of beetles in the treatment and control traps, and the total number of beetles released in the olfactometer, respectively. ** indicates significant differences between the treatment and control traps (Wilcoxon matched-pairs signed-ranks test: P < 0.01, n = 10).
