What does "pesticide resistance" refer to?

Pesticide resistance refers to a change in the genetic pool of a species that enables certain individuals within a pest population to survive exposures to pesticide chemicals that would typically be lethal. Over time, through the processes of natural selection, pests that possess genetic traits that confer resistance are more likely to survive and reproduce, leading to a population that is increasingly tolerant to the pesticide. This phenomenon can occur with prolonged and repeated use of the same pesticide, as those pests that are susceptible to the chemical are eliminated, while resistant individuals thrive and propagate their resistance traits.

This concept is significant in pest management and integrated pest management strategies, as it highlights the need for rotation of pesticides with different modes of action to mitigate resistance development. Resistance not only makes controlling pest populations more challenging but can also lead to greater economic and environmental costs associated with increased pesticide use and failure to achieve satisfactory pest control.