Which of the following symptoms is NOT caused by nematodes?

The symptom described as reduced sunlight to plants is not caused by nematodes. Nematodes are microscopic roundworms that can infest plant roots and contribute to various issues such as wilting, yellowing leaves, and the formation of bare patches in grasses.

When it comes to reduced sunlight, this condition is generally related to environmental factors such as shading from nearby structures, the density of vegetation, or issues with plant health that affect how effectively they can photosynthesize. Nematodes do not have a direct influence on the amount of sunlight that reaches the plants, making this symptom unrelated to nematode activity. In contrast, symptoms like wilting, yellowing leaves, and bare patches are directly linked to the damage and stress caused by nematodes feeding on plant roots, ultimately disrupting nutrient uptake and plant vitality.