Agronomy Degree Practice Exam

What term is used to describe localized death of leaf tissue?

1. Chlorosis

2. Firing

3. Rusting

4. Necrosis

The correct answer is: Necrosis

Localized death of leaf tissue is referred to as necrosis. This term specifically denotes the irreversible damage and eventual death of cells or tissues in a plant caused by various stress factors such as disease, environmental conditions, or nutrient deficiencies. When necrosis occurs in leaf tissue, it is often characterized by yellowing and browning of the affected areas before they die completely, leading to spots or patches on the leaves. Chlorosis, by contrast, indicates a condition where leaf tissues turn yellow due to insufficient chlorophyll, without outright cell death. Firing generally refers to the process of leaves or plant material becoming desiccated and brown, but it does not specifically capture the idea of localized tissue death. Rusting refers to a particular type of fungal disease that causes rust-colored spots on leaves but is not a direct synonym for localized tissue death.