Which part of the plant do nematodes primarily infect?

Nematodes primarily infect the roots of plants, which is why the correct choice is roots. This is significant because the root system is essential for plant stability, water uptake, and nutrient absorption. When nematodes infest the roots, they can cause damage that leads to stunted growth, wilting, and overall decline in plant health.

Understanding the biology of nematodes is crucial, as they can enter the plant tissue and disrupt normal physiological processes. This root infection can result in galls, lesions, or even complete necrosis of the roots, severely impacting the plant's ability to thrive. Identifying this area of infestation aids in effective pest control methods and managing the health of crops.

Other parts of the plant, such as the leaves, stems, and fruits, can be affected by different types of pests or diseases, but nematodes have a specific affinity for the root zone, making their impact concentrated there.