Insecticide resistance governed by gut symbiosis in a rice pest, under laboratory conditions.

Resistance to toxins in insects is generally thought of as their own genetic trait, but recent studies have revealed that gut microorganisms could mediate resistance by detoxifying phytotoxins and man-made insecticides. By laboratory experiments, we here discovered a striking example of gut symbiont-mediated insecticide resistance in a serious rice pest, . The rice bug horizontally acquired fenitrothion-degrading through oral infection and housed it in midgut crypts. Fenitrothion-degradation test revealed that the gut-colonizing retains a high degrading activity of the organophosphate compound in the insect gut. This gut symbiosis remarkably increased resistance against fenitrothion treatment in the host rice bug. Considering that many stinkbug pests are associated with soil-derived , our finding strongly supports that a number of stinkbug species could gain resistance against insecticide simply by acquiring insecticide-degrading gut bacteria.