What is a systemic pesticide?

A systemic pesticide is a type of pesticide that is absorbed by plants, allowing it to move throughout the plant's tissues. This characteristic enables the pesticide to target pests that feed on the plant, as it becomes part of the plant's system. When insects or other pests consume the plant, they inadvertently ingest the pesticide, which can lead to their control or elimination.

Systemic pesticides are particularly effective for managing sap-sucking insects or internal feeders that may not come into direct contact with the pesticide in the soil or on the surface of the plant. This method of action provides a more comprehensive solution against various pests since it works internally rather than relying solely on contact with the pest.

Considering the other options, a pesticide that kills on contact directly impacts only those pests that come into contact with it, and thus does not utilize the plant's absorption capabilities. A pesticide that is only effective in the soil would not be absorbed by the plant or offer protection against above-ground pests. A pesticide that repels pests primarily keeps them away rather than targeting them once they enter the plant's system. Each of these definitions lacks the specific action of being absorbed and transported throughout the plant, which is what characterizes a systemic pesticide.