Alabama OTPC Practice Test

The idea being tested is how a chemical can prepare a crop for harvest by causing leaves to fall off. A defoliant is used specifically to induce leaf drop, helping harvesters move through fields more cleanly and reducing leaf debris in the harvested product. It works by triggering abscission at the leaf petiole, so leaves detach from the plant.

Desiccants, by contrast, dry plant tissues to speed up harvest but don’t primarily cause leaves to shed. Acaricides target mites, and fungicides target fungi, so they don’t accomplish leaf removal either.