Insect Resistance

uResistance to Product B resulted from exposure to Product A/B

Cross resistance

Resistance to Product A and B resulted from exposure to Product A/B

Multiple resistance (assuming seperate MoA)

How quickly does insect resistence appear with new products?

In 2-20 years typically.

WHat was the first organic resistance reported?

Resistance to DDT in 1947

How do insects become resisant? (4 ways)

1. target site resisance

2. metabolic resistance

3. behavior shift to avoid product

4. penetration shift to avoid pesticide infiltrating

What is vital about dominant vs recessive resistance?

Dominant would create problems extremely quickly as it would appear in every phenotype.

What make up the selection pressures of a pesticide?

Insecticide activity (selection pressure)

Efficacy/mode of action

Specific/non-specific (multiple) mode of action

Eggs, immatures, adults

Protected sites (systemic/contact)

Residual activity/Multiple applications

Relative to pest life cycle

What occurs to resistant individuals vitality?

It typically has a metabolic cost that makes them weaker outside of systems.

What is a window of application?

When 2 pesticides with same MoA can be applied

What determines application window?

The amount of residual activity and generation time of pest.

What is the goal of window of application

Have a generation of insects be exposed to as little of same MoA as possible to reduce risks of resistance.