What is the difference between contact pesticides and systemic pesticides?

Contact pesticides and systemic pesticides differ significantly in their modes of action and application methods. Contact pesticides are designed to affect pests when they come into direct contact with them, meaning they must be sprayed directly on the insect or pest for effective control. This type of pesticide works primarily on the surface of the plant and does not infiltrate the plant tissues.

In contrast, systemic pesticides are absorbed by the plants and move throughout their tissues, including the leaves, stems, and roots. When pests feed on parts of the plant that contain these systemic pesticides, they are affected and typically killed. This method is particularly effective for controlling pests that can be difficult to reach or that might not make contact with the pesticide directly.

Understanding this distinction is crucial for effective pest management and choosing the right pesticide based on the specific situation and target pests. The correct answer highlights the key differences in how each type of pesticide interacts with pests, emphasizing the direct contact requirement of contact pesticides as opposed to the absorption and translocation capabilities of systemic pesticides.