Figure 2

Compared experimental (black dots + bars: m ± s.e.) and modeled additive (bold lines) responses of American palm weevils to mixtures of synthetic aggregation pheromone (P) and natural odor of fermented sugar cane (K) in a 4-arm olfactometer for three flow rates (0.3, 0.03, 0.003 ng/s; #: actual flow rates s of 0.0033, 0.033 and 0.33 ng/s for pure K) and five P:K ratios (P: 0, 25, 50, 75, 100%). There is synergy (experimental significantly greater than predicted additive response) with: *: p-value < 0.05, **: p-value < 0.01, or ***: p-value < 0.001 (Student t-test). Straight lines at 322 and 145 s: minimum (m) and maximum (M) expected responses under the hypothesis of additive effects of P and K respectively.