What is Turnip Black Rot?
Turnip black rot is a serious disease that can affect turnips and other vegetables in the Brassica family, such as cabbage, broccoli, cauliflower, kale, mustard, and radish. It is caused by a bacteria called Xanthomonas campestris pv. campestris.
The bacteria enters the plant through leaf pores and moves down into the vascular system, which carries water and nutrients throughout the plant. Infected leaves will have a notched or “V” shaped lesion at the leaf margin and may have black to dark grey fibers running through the leaf tissue. Once the leaves are infected, they will rapidly degrade and the plant may collapse and rot.
Turnip black rot was first described in 1893 and has been a problem for farmers ever since. It is spread by splashing water, windblown water, animals, and people moving through the crop. The disease is most prevalent in warm, wet weather and can spread rapidly, even before any symptoms are visible.
How to Identify Turnip Black Rot
The first signs of turnip black rot will appear on the lower leaves of the plant. The leaves will have a notched or “V” shaped lesion at the leaf margin and may have black to dark grey fibers running through the leaf tissue. As the disease progresses, the leaves will rapidly degrade and the plant may collapse and rot.
How to Prevent Turnip Black Rot
There are several things you can do to prevent turnip black rot:
- Plant turnips in areas that have been free from cruciferous debris for over a year.
- Use disease-free seed or resistant varieties.
- Keep the area around the turnips weed free.
- Sanitize garden equipment to prevent the spread of the disease.
- Use a drip irrigation system or water plants at their roots to avoid splashing water.
- Remove and destroy any cruciferous crop debris.
How to Treat Turnip Black Rot
If you find turnip black rot in your garden, there are a few things you can do to treat it:
- Apply bactericides at the first sign of leaf infection.
- Repeat the application weekly while weather conditions favor the spread of the disease.
- Remove and destroy any infected plants.
Additional Information
- Turnip black rot is a serious disease that can cause significant crop losses.
- The disease is caused by a bacteria called Xanthomonas campestris pv. campestris.
- Turnip black rot is spread by splashing water, windblown water, animals, and people moving through the crop.
- The disease is most prevalent in warm, wet weather.
- There are several things you can do to prevent and treat turnip black rot.
By following these tips, you can help to protect your turnip crop from black rot.
