Fig. 5.

Effects of indole analogs on AFB disease. Honey bee larvae were challenged with P. larvae spores in larval diet supplemented with water (crosses), 500 µM of 5-bromoindole (filled circles), 500 µM of 5-cholorindole (open squares), 500 µM of 5-nitroindole (filled squares), 500 µM of 6-bromoindole (open triangles), or 500 µM of 6-cholorindole (filled triangles). Unchallenged larvae (open circles) were used as experimental control and showed >95% survival. Differences between survival curves were determined using Kaplan–Meier analysis, log-rank test (χ²=194.484, df = 6, P < 0.001), and the Holm–Šidák method (P < 0.05).