A disease that strikes tomatoes and potatoes, can quickly ruin an entire crop — and provide a source of infection for other plants. It is critical that gardeners understand that late blight is not like other tomato and potato diseases. Many other diseases affect these crops in home gardeners, but most of them only affect leaves or cause limited damage to fruit, and while they may reduce the harvest, they generally don’t cause a total loss. Furthermore, because most pathogens are not readily dispersed by wind, their effects are localized. Late blight, on the other hand, kills plants outright, and it is highly contagious. Its occurrence in your garden can affect other gardens and farms due to the wind-dispersed spores.
Blossom End Rot:
Nutritional disorder, not a disease. (calcium deficiency) Sunken brown or black patches on the blossom end of the fruit. Caused by too much nitrogen, acid soil, uneven watering or high humidity. These conditions inhibit the plants intake of calcium. Correcting these has always worked for me, but if you still have blossom end rot, one of the liquid calcium products available at garden stores should do the trick.
Catface or Scarring: Caused by injury to the plant during blossoming, often from a period of cold weather.
Tobacco Mosaic Virus:
Leaves become mottled with yellow and green mosaic patterns. Brown sunken rings in fruit.
Over winters in the soil. Wilts during the day but perks up at night.
What To Do for Tomato Diseases
The fruit may still be used, but production will be less. With most of the wilt diseases, about the only options are to rotate planting locations every year. (always a good idea anyway) Attempt to sterilize the planting area with solar heat using clear plastic, grow varieties resistant to the type of wilt you have, or just live with it.