There are 7 common plant protection terms you will need to know to better understand plant protection. 

Active constituent (ai)

The component in the product that actually does the job.



The active constituent enters and moves around in the plant’s sap and water system. This means it can affect pests that attack the plant while it is active within the plant.


The product works by directly contacting the pest.

Stomach poison

Affects leaf chewers and suckers that ingest plant material.


The product can be sold for the purpose claimed on the packaging

Withholding period

The time that must pass after application of a pesticide before crops can be harvested

Signal heading

The message above the product name that gives some indication of the toxicity of the product.

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