How can pesticide resistance develop in pests?

• A. Through the natural evolution of pests
• B. By introducing new pesticides every season
• C. Through overuse or improper application of pesticides
• D. By rotating different crops each year

Answer: (C)

Pesticide resistance in pests primarily develops through overuse or improper application of pesticides. When pesticides are applied extensively to manage pest populations, those pests that possess or develop genetic traits allowing them to survive exposure to the chemicals are more likely to reproduce. Over time, these resistant individuals become more prevalent within the pest population, leading to a situation where the pesticide is less effective or entirely ineffective against them.

This resistance can be exacerbated by factors such as applying the same classes of pesticides repeatedly without integrating alternative pest management strategies. Additionally, improper application, such as using insufficient dosages or applying them under conditions that reduce efficacy, can contribute to the survival of resistant pests while non-resistant ones are controlled. Therefore, the continuous presence and selection pressure of pesticides can lead to increased resistance.

In contrast, while natural evolution of pests does occur, it is the selective pressure from the frequent and improper use of pesticides that accelerates the process of developing resistance. Introducing new pesticides every season could potentially delay resistance if done correctly, but it might not prevent it if those new pesticides fall within the same mode of action. Rotating different crops can help disrupt pest cycles and reduce pressure, but this practice does not directly cause pesticide resistance on its own.