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Defend Vegetables Against Diseases
By Allison Powe
MISSISSIPPI STATE -- Spring fever often comes to Southerners in the form of mouth-watering anticipation for fresh home-grown vegetables, but garden diseases can quickly spoil appetites.
Maintaining healthy vegetables in home gardens requires continuous efforts to care for the plants throughout the growing season. This year's cool, wet weather may make the task more difficult.
"This spring's weather conditions have made disease control very important," said Dr. Frank Killebrew, extension plant pathologist at Mississippi State University.
"Vegetables will be more susceptible to various fungal diseases this year because of the high amount of rain and cool temperatures we have experienced," Killebrew said.
Early blight on tomatoes, leaf spots on turnip and mustard greens, and seedling diseases of beans and peas have been common in gardens across the state.
"Fungicides applied at planting time can control seedling diseases on beans and peas. Later fungicide applications can combat early blight on tomatoes and leaf spots on turnip and mustard greens," Killebrew said.
"A number of approved fungicides for early blight and other fungal diseases are available in garden supply stores. When used according to label directions, these fungicides will help reduce fungal diseases," Killebrew said.
The plant pathologist recommended using fungicides containing chlorothalanil to control tomato early blight and copper-containing fungicides such as Kocide 101 to control leaf spots that thrive in wet conditions on turnip and mustard greens.
Killebrew said it is important to start a fungicide application program before diseases become widespread. Fungicides are of little value once a disease has done much damage.
Wet weather conditions have left all garden plants more susceptible to fungal diseases. Seeds are also more likely to rot in the wet ground.
Killebrew said fertilizers are valuable tools in a gardener's disease control program because they help grow stronger, healthier vegetable plants which tend to be more resistant to diseases.
He recommended taking a soil sample from garden areas to be tested for fertility and nematodes.
"Soil tests can determine fertility needs of garden areas which lets a gardener know exactly how to fertilize vegetables," Killebrew said.
Nematodes are microscopic worms in soil that feed on roots of susceptible tomatoes, peas and other garden vegetables.
"If tests indicate a nematode problem, gardeners can plant nematode-resistant vegetable varieties," Killebrew said.
Gardeners also have the options of rotating crops and using non-host plants that are not susceptible to nematodes.
"Gardens still have a good chance of being successful and producing healthy plants. Begin a fungicide application program to protect the plants from diseases that are common during wet weather, and if you see any sign of disease, take preventive action quickly to avoid spreading," Killebrew said.
For further information or to obtain a soil-testing package, contact your local county extension office.