Fusarium Wilt

This disease is caused by a fungus that can persist in the soil for many years. The fungus enters the roots or the stem near the soil surface and spreads upwards through the xylem or water-conducting plant tissues. Symptoms include wilting of the lower leaves, which turn yellow and then brown. Wilting slowly moves upwards as the disease continues. Make a cross-section of the stem several inches above the soil level and look for dark-brown discolored tissue underneath the outer stem tissue.

Control: Immediately remove and destroy infected plants. There is no chemical control. Plant resistant varieties--look for an "F" after the variety name in the catalog or on the seed packet. Each year rotate tomatoes to another area of the garden.