What pathogen causes Fusarium wilt in tomatoes?

The pathogen responsible for Fusarium wilt in tomatoes is Fusarium oxysporum f. sp. lycopersici. This specific strain of the Fusarium oxysporum species targets tomato plants, leading to the characteristic symptoms of wilting, yellowing of leaves, and ultimately plant death. The disease primarily affects the plant's vascular system, inhibiting water and nutrient movement, which is critical for plant health and growth.

Understanding the importance of this particular pathogen is crucial for effective disease management in tomato cultivation. The other options refer to different pathogens or pests that affect various plants. For instance, Rhizoctonia oryzae-sativae is associated with rice; Pyricularia grisea impacts grasses, particularly rice, causing blast disease; and Phytonemus pallidus is a mite that affects plants in different ways, but is not linked to Fusarium wilt in tomatoes. Therefore, recognizing that Fusarium oxysporum f. sp. lycopersici is the causative agent of Fusarium wilt is essential for identifying and managing the disease in tomato crops effectively.