Fig. 4.

Toxicity of indole analogs on honey bee larvae. Honey bee larvae were reared in larval diet supplemented with water (open circle), 500 µM of 5-bromoindole (filled circle), 500 µM of 5-cholorindole (open square), 500 µM of 5-nitroindole (filled square), 500 µM of 6-bromoindole (open triangle), or 500 µM of 6-cholorindole (filled triangle). Surviving larvae were counted daily. Differences between survival curves were determined using Kaplan–Meier analysis, log-rank test (χ²=19.422, df = 5, P < 0.002), and the Holm–Šidák method (P < 0.05).