FLY CONTROL

How resistance develops

How IPM interrupts it

In any population of flies, a certain small number is born genetically resistant to the given dose of insecticide. Some will survive treatment.

Non-insecticidal control methods, such as eliminating breeding sites and using natural insect predators, help kill or prevent development of resistant insects along with the susceptible ones.

Those surviving, resistant individuals mate with other survivors in the environment. Offspring inherit resistance, reproduce themselves, and begin to populate the area resulting in a higher number of resistant flies.

By coordinating insecticide use on your operation and with neighbors so no single class is being used exclusively, resistant flies have less opportunity to mate.

Because treatment with pesticides continues to kill susceptible lines, the resistant flies face less and less natural competition for food. Over time, the resistant group thrives. The spread of resistance is accelerated in the South, where the climate allows flies to produce several generations with a single season.

If you supplement tags with a different class of insecticide delivered through pourons, oilers, dust bags and sprays, you stand a better chance of killing insects resistant to the tag chemical before they thrive.

Continued treatment with the same class of insecticide gradually weeds out most or all susceptible flies, even as the resistant percentage grows unchecked.

Removal of insecticide ear tags at the end of the season reduces the amount of active ingredient that remains in the environment over time. That removal of low levels of insecticide allows susceptible lines to recover and compete with resistant lines, diluting the level of resistance.

The insecticide eventually fails when the population becomes predominantly resistant insects.

By rotating to a new chemical class the following year, you are likely to kill the resistant population so the cycle of resistance development must begin anew, rather than begin from the point where it left off last year.