Many vegetable gardeners, especially those in the East and Midwest, know early blight tomato disease all too well. It first appears in summer as brown spots on lower leaves. Eventually it spreads, turning leaves yellow, killing them, and reducing tomato production. In bad years, the plant may be prematurely defoliated with the disease on leaves, stems, and fruits, with few usable fruits. Although crop rotation, mulching, and preventative fungicidal sprays can help lessen the damage, two home garden varieties now on the market were specifically bred for their resistance to early blight. Randy Gardner, tomato breeder at North Carolina State University in Raleigh, has bred 'Mountain Supreme' and 'Plum Dandy', both of which have moderate resistance to early blight. While they may eventually get the disease, the plants are strong enough to produce a full crop of fruit without the need for fungicidal spraying.
Both 'Mountain Supreme' and 'Plum Dandy' are determinate plants with a dense foliage cover to protect the fruit from bad weather, and they're highly resistant to all types of skin cracking. The round, red, 6- to 8-ounce fruit of 'Mountain Supreme' matures in 75 days. It also has high resistance to fusarium wilt and moderate resistance to verticillium wilt. 'Plum Dandy', a Roma type, averages 3 ounces and matures in 70 days. It is highly resistant to both kinds of wilt but susceptible to bacterial spot. It grows best in cool-summer areas where night temperatures remain below 70° F.
Beth Marie Renaud was executive editor at National Gardening.
Article published on June 23, 2008.