Manage tomato plant problems
Home- grown tomatoes are the most popular garden vegetable in Arkansas. Tomatoes are fairly easy to grow and just a few plants can provide an adequate harvest for most families. However, tomatoes suffer from physiological disorders and numerous infectious diseases. They are very sensitive to herbicide drift injury. Physiological disorders: Blossom- end rot, a dry, leathery rot on the blossom end of fruit, is common in homegrown tomatoes. It is caused by a combination of calcium deficiency and wide fluctuations in soil moisture.
Fruit cracking is caused by soil moisture fluctuations. When the tomato reaches the mature green stage, reduce or cut off the water supply to the plant as the tomato begins to ripen. At this time, the skin around the outer surface becomes thicker and more rigid to protect the tomato during and after harvesting. If the water supply is restored after the ripening begins, the plant resumes translocation of nutrients and moisture into the fruit. This causes the fruit to enlarge and skin splits around the fruit.
Lack of fruit set, or flower drop, is caused by unfavorable weather ( night temperatures lower than 55 F or above 72 F and day temperatures reach above 95 F with dry, hot winds) during flowering and early fruit development. Bacterial diseases: Bacterial speck disease is favored by cool, wet weather and is more common during spring months in Arkansas. It is spread on seed or infected transplants and is moved about by splashing water, workers or machinery. It can survive in infected crop debris for several months and can live on various weeds. This disease causes small round, dark spots on leaves. Use only bacterial speck- free seeds or transplants from a reliable supplier. Eliminate nearby weeds or volunteer tomato plants. Rotate tomatoes to new soil areas every two years.
Bacterial wilt disease can cause rapid death of infected plants. It can infect many other plants. The bacterium can survive in the soil for months, especially in well- drained soils. It is spread by soil and water movement, diseased plants or infected debris. Early symptoms are a slight wilt of the youngest leaves, followed by a rapid wilt within two to three days. The root system will develop a brownish rot as the plant dies. Disease is favored by hot, dry weather. Destroy infected plants immediately. Grow on raised beds to promote drainage. Fungal diseases: Early blight is a very common disease of Arkansas tomatoes and is favored by warm, rainy weather. Spots form on leaves, stems and fruit, and start as small, dark brown areas sometimes with a yellow border. Leaf spots grow rapidly under favorable conditions, forming lighter brown bands with a dark center. Spots are leathery feeling and may be covered by a blackish dust. Infected fruit often drops off soon after infection. Grow resistant varieties. Eliminate weeds and rotate to other areas every two years. Use proper fertilization and a fungicide.
Southern blight is a problem in soils that have grown tomatoes for several years. The fungus survives as hard, brown “sclerotia” that look like tiny BBS in the soil. Sclerotia can survive for several years without a host. A large, brown to dark brown rot appears on the stem at the soil line, which spreads up and around the stem causing a rapid wilt of the plant. Usually a white, cottony growth develops over the surface of the rot area and sclerotia form on the white growth over a period of a few days. If young plants are infected, they may fall over at the soil line. Plastic mulch may help somewhat. Fertilize with calcium nitrate to minimize disease; use fungicides.
Verticillium wilt is a disease favored by long- term tomato production, cool weather and high ph soils. The fungus survives as micro- sclerotia in infected crop debris and can attack other plants. Its symptoms are often confused with fusarium or bacterial wilt. Infected plants may wilt only slightly at first, usually during the hottest part of the day, and recover at night. Later, lower leaves may show whitening or yellowing between the veins. Grow tomato varieties with disease resistance when possible. Rotate tomatoes for two years. Destroy all weeds on a regular basis and destroy all infected plants immediately.
Remember, herbicide drift injury can cause the young leaves of tomato plants to become pointed and have irregular shapes.
4- H For information on 4- H, call the Extension office, 623- 6841 or 922- 4703, or email Sara Waller, swaller@ uaex. edu.
Master Gardener Call the Extension office or email Allen Bates, abates@ uaex. edu, for information on Master Gardeners.
EHC For information on Extension Homemakers Club, call the Extension office or email Lisa Washburn, Lwashburn@ uaex. edu.
Poultry Swap Meet A Poultry Swap Meet will be held starting at 8: 30 a. m. June 9 at Garland County Fairgrounds. There will be chickens, ducks, turkeys, geese and small animals. Testers will be on site from 6- 8 a. m. for a fee. Proceeds will benefit the Garland County Youth Premium Sale. For information, call Phillip, 627- 2646, or Michael, 627- 2590.