(Including Tubers, Corms, and Other Propagate Plant Parts)
Many diseases can be controlled by a simple chemical seed treatment. Plant disease organisms survive from season to season through spores carried on or in seeds. Some chemical seed treatments provide a protective zone around the seed through which soil-borne organisms can not penetrate. The young seedling is protected from attack until it is capable of outgrowing attacks from soil-borne pathogens. Some plant disease organisms are carried inside the seed. As the seed germinates, the fungus grows along with the developing seedling, eventually causing disease symptoms in the mature plant. One example of this kind of fungus is loose smut of wheat and barley. These internal infections can only be controlled by systemic seed treatments.
There are many fungicides recommended for different fungi that attack seedlings. No one seed treatment will work to control this diverse group of pathogens. A material that is highly effective in controlling a disease in small grains may not be effective on vegetable seed. These seed treatment chemicals vary considerably in their toxicity to humans and animals. Great care should be taken when working with these materials. You should always read the label before proceeding and follow the label precisely. Some materials may not be poisonous, but dust from the treatment may be irritating to the eyes and nose. Chemically treated seed should never be used for human or livestock feed. Seed treatment is our first line of defense against plant disease. Various materials for seed treatment are discussed in this publication under specific crop sections.