Which process involves the breakdown of pesticides by the action of sunlight?

The process that involves the breakdown of pesticides by the action of sunlight is known as photodegradation. This term specifically refers to the chemical reactions that occur when compounds are exposed to ultraviolet (UV) radiation from sunlight, leading to the breakdown of those compounds into simpler substances. Photodegradation is significant in the context of herbicides, as it affects their persistence in the environment and influences their efficacy and potential environmental impact.

Understanding photodegradation is crucial for evaluating how long a pesticide will remain active in the environment and how it may degrade, ultimately influencing application timing, effectiveness, and safety. Other degradation processes like microbial degradation involve living organisms breaking down substances, while chemical degradation refers to the breakdown through other chemical reactions without the specific involvement of sunlight. Dry degradation is not a recognized term in this context. Thus, photodegradation accurately captures the specific mechanism of sunlight-induced pesticide breakdown.