That same mineral you may be using in your ration may be keeping the bugs in the field from getting sick. The latest research out from USDA’s Ag Research Service suggests that moderate dietary levels of selenium may actually strengthen insect immunity. Typically, high levels of selenium are toxic to pests, but studies with cabbage looper moths and tobacco budworms found that the group raised on artificially high, though not toxic, levels of selenium had a stronger immune response system, therefore lowering the effectiveness of microbial biological control agents used against them.

ARS is hoping to further the findings of this study to benefit crop growers in their integrated pest management strategies.