1) Tomato Fusarium wilt is caused by the soil-borne fungus Fusarium oxysporum f. sp. lycopersici. It is specific to tomatoes and can cause 10-90% yield losses.
2) Symptoms include leaf chlorosis, wilting, and brown vascular streaking. Stems of infected plants show brown discoloration.
3) The fungus survives for over 10 years in soil or plant debris. Infection occurs through wounds and spreads systemically through the xylem. Warm temperatures and high nitrogen soils promote disease.