Bacterial Speck favors environments with low temperatures (65-75oF / 18-24oC) and high-moisture conditions.
It can survive on infected plant material in the field for up to 30 weeks. It may also surivive on a number of weed species. It's survival in bare untreated soil is generally less than 30 days.
This bacterium is probably spread across distances by infected transplants and on seeds so care should be taken not to plant infected seed or to treat seed in a mild bleach soak prior to planting. The disease is also spread by splashing water or mechincal means (handling or touch of plants with infected hands or tools).
If you suspect this disease it is best to throw out all infected plant material. Care should be taken to also remove possibly infected weeds. Some bactericides, often copper based, can be used as a control measure in areas prone to bacterial speck. Check first with state university, county agent or nursery for what bactericide is recommended for your area.
There is a small, egg-shaped variety called "Enchantment" that has some resistance to bacterial speck.
