Pesticide Resistance Factors

Pesticide Resistance Factors

Biological and Ecological Factors Affecting Development of Pesticide Resistance

June 19, 2015

This is one of a number of CropWatch articles focusing on resistance management. See more and learn how to reduce the risk of resistance developing on your farm.

Pesticide resistance is a decreased response of a pest population to a pesticide as a result of previous exposure.  It can be thought of as kind of accelerated evolution, where a pest population is exposed to a selection pressure, in this case a pesticide, and over time the "response" of the population may result in resistance.

Pesticide resistance management can be defined in a variety of ways, depending on your perspective:

  • A process of delaying the development of resistance in a pest population.
  • A set of methods designed to extend the number of generations that a given pest population can be controlled economically with a given technology.
  • Managing gene flow and selection.

Factors Affecting Resistance Development of the "Pest" in the Environment

Pesticide-resistance management page
Learn more about resistance management through this interactive learning activity.

Pesticide resistance occurs in an ecological context where biological and environmental factors are constantly interacting. These factors can be divided into biological, behavioral, and operational.

  • Biological factors that can affect resistance development include characteristics of:
    • an organism's life cycle,
    • the organisms rate of its population growth, and
    • the genetics of the organism.
  • Behavioral factors that can influence the development of resistance include:
    • movement
    • exposure
  • Operational factors are the things we do to manage pest populations and interact with all the previous factors. Manipulating these operational factors varies selection pressure and is important in resistance management.

To better understand how these factors and their interactions can influence the development of pesticide resistance, visit the online educational module at: http://passel.unl.edu/communities/pesticiderm and click on "Biological/Ecological Factors" to begin the module.

Gary Hein
Director, UNL Doctor of Plant Health Program