Nematode infection increases risk of fusarium infection. Small whitish rings, 1-3 mm diameter, on green tomatoes. Warmer, drier conditions control. Also on peppers, eggplants, ground cherries, etc. Dark brown spots on underside of leaves in warm, humid weather.
Affected leaves turn yellow, wither, drop.
Serious infections will keep plants from fruiting. Bordeaux mixture will treat. Heavy gray growth on dead leaves or stems at the base of the plants. Tan markings appear on stems, gray spots on live leaves, and gray or yellow soft spots on the fruits. Usually a spring disease that will let up in higher temperatures or lower humidities.