Which nutrient deficiency is typically associated with the symptoms of chlorosis in younger leaves?

Chlorosis in younger leaves is primarily associated with iron deficiency. Iron is an essential micronutrient that plays a crucial role in the chlorophyll synthesis process. When a plant lacks adequate iron, it struggles to produce sufficient chlorophyll, resulting in yellowing of the younger leaves while the older leaves may remain green. This phenomenon occurs because iron is not mobile within the plant; thus, it affects newer growth first.

The other nutrients listed do have their own deficiency symptoms, but they typically do not manifest as chlorosis in younger leaves. For example, phosphorus deficiency can lead to darkening or purpling of leaves but is not specifically associated with younger leaves. Sulfur deficiency can also cause yellowing, but it generally affects older leaves first. Potassium deficiency tends to lead to overall reduced vigor, edge browning, and necrotic leaf spots rather than specific chlorosis in younger leaves. This understanding reinforces the importance of identifying nutrient deficiencies correctly for effective plant care and management.