A Nematode is a microscopic, slender worm-like animal, less than 1/16 inch long, that lives in the soil, water and plant tissues, and attacks plants. Root nematodes live in the soil and feed on plant roots. Foliar nematodes live in stems and leaves. Nematodes may be found wherever there is moist, rich soil. They move from garden to garden on transplants, garden tools, water, ants, and shifted earth.
Root knot nematodes attack tomato roots, and other vegetable crops and cause root nodules that block the flow of water and nutrients to plants. Nematode damage causes leaves to yellow and become wilted or stunted. Roots look stunted and show lumpy nodules that shelter nematodes and help them siphon off nutrients and water. Infected plants don't respond to fertilizing, and regardless of proper watering, they wilt in hot weather.
Pull and destroy infected plants, including roots. Best control is to plant resistant varieties, and utilize crop rotation and soil solarization methods.