Fig. 1.

Phenotyping of mosquito larvae exposed to Bti. A dose of 1 μg suspension of Bti spores/crystals was applied every hour to each of the 530 larvae individually disposed in plastic cups containing 20 ml of tap water. Thirty larvae were sampled before exposure to Bti and formed the “control” group. The number of dead larvae sampled at each time point is indicated in the figure. Larvae were separated into three subgroups: “Susceptible” (larvae dead in less than 6 h of exposure to Bti), “Intermediate” (larvae dead between 6 and 11 h) and “Tolerant” (larvae dead after 11 h), which are represented in green, blue and orange, respectively. The bar hatched corresponds to six larvae still alive after 25 h of exposure to Bti