What is the process called when a leaf turns yellow due to a deficiency, typically of iron?

The process of a leaf turning yellow due to a deficiency, especially of iron, is known as chlorosis. This term specifically refers to the yellowing of plant tissues, which occurs when there is insufficient chlorophyll production. Chlorophyll is essential for the green coloration of leaves and is crucial for photosynthesis. In cases where iron is deficient, the plant is unable to synthesize chlorophyll effectively, leading to the characteristic yellowing.

Chlorosis can occur in various parts of a plant but is most commonly observed in young leaves, which may exhibit yellow veins while the leaf blades remain green. This is typically due to iron being more mobile within the plant, and younger leaves being the first to show signs of deficiency.

The other terms listed do not pertain to this specific process. For instance, "clone" relates to a form of asexual reproduction in plants, while "caliper" is a measurement term used in horticulture to describe the diameter of a tree trunk at a specific height. Understanding the significance of chlorosis can help in diagnosing plant health issues and determining appropriate fertilization methods to rectify nutrient deficiencies.