Using the same pesticide or a different brand with the same mode of action for multiple years does what to pesticide resistance?

Using the same pesticide or a different brand that operates under the same mode of action for multiple years increases the likelihood of developing pesticide resistance in target pest populations. This phenomenon occurs because consistent exposure to the same type of pesticide selects for individuals within a pest population that may possess or acquire genetic traits allowing them to survive despite the application of the chemical.

As these resistant individuals reproduce, they pass on their resistance traits to the next generation, leading to a population that increasingly tolerates the pesticide. Therefore, rotating different classes of pesticides with varying modes of action is recommended to manage and mitigate the risk of resistance, thus preserving the effectiveness of these chemicals over time.