Blight-resistant Organic Tomato Seeds

Early Blight

• Early and late blight are both fungal pathogens that can decimate a tomato crop. Early blight is caused by Alternaria solani. The first symptoms of early blight include small, irregular brown spots on lower leaves, eventually forming target-like circles. Circular, sunken brown lesions can be seen on the stems, and the plant is often defoliated. Tomatoes are then exposed to the sun, causing sun scald. Fruit production decreases, and fruit size diminishes.

Late Blight

• Late blight is caused by Phytophthora, literally meaning "plant destroyer" in Latin. Late blight causes significant damage not only on tomatoes, but also on potatoes. Fungal pathogens overwinter on potato tubers, become airborne and can infect your tomato plant. Once a plant has become infected by late blight, the plant is usually dead within days. Cornell University is currently breeding new varieties resistant to late blight.

Blight-resistant Varieties

• In January of 2011, Cornell Cooperative Extension published a tomato chart listing all blight-resistant tomato varieties and where they can be purchased. Tomatoes listed as being resistant to early blight include Cabernet, JTO-99197, Juliet, Manalucie, Manyel, Matt's Wild, Merlot, Mt. Fresh Plus, Old Brooks and Tommy Toe. Late blight--resistant varieties include Golden Sweet, Juliet, Legend and Old Brooks. These seeds can be purchased from a variety of growers, but you will need to double-check with each grower to determine whether the seeds are organic.

Organic Seed Production

• Small farmers started growing organically in the 1940s, and by 1980, organic produce sales were so high that a regulatory agency, the Organic Certification Board, was established, and the Organic Foods Production Act was passed. Organic growers are required to use organically grown seed if it's commercially available. Seed companies are branching out into the organic seed market and are offering small, homeowner-size packets. More varieties will become available on the market, including a larger selection of blight-resistant varieties of tomatoes.