Raccoons and deer will also eat tomato plants and fruit. Alleopathy: Roots are inhibited by the presence of a chemical released by another plant, such as, black walnut. Tomatoes should not be planted within 50 feet of the drip line of a black walnut. Diseases: There are many diseases of tomato not listed here. Some caused by bacteria, some fungal, some viral, some nematodes and others with unknown causes. Visit our website for information on how to contact us and ask questions.