13
Tomato Buckeye Rot: A Comprehensive Guide
Introduction
Imagine your beautiful tomatoes developing large, brownish spots with rings that resemble a buckeye nut. If these spots are near the blossom end or where the tomatoes touch the soil, it’s likely that your plants have buckeye rot, a fruit-rotting disease caused by a fungus that lives in the soil.
What is Tomato Buckeye Rot?
Tomato buckeye rot is caused by three types of Phytophthora fungus: P. capsici, P. drechsleri, and P. nicotiana var. parasitica. These fungi thrive in warm, wet conditions, especially in the southeastern and south-central United States.
Symptoms of Tomato Buckeye Rot
- Small, brownish, water-soaked spots on the fruit, usually at the point of contact between the fruit and the soil
- Spots gradually enlarge and develop alternating rings of light and brown bands
- Lesions become rough and sunken, with a white, cottony fungal growth in the center
Causes of Tomato Buckeye Rot
- Infected seeds or transplants
- Volunteer tomato plants or previous crops in the same location
- Poor soil drainage
- Soil compaction
- Prolonged periods of wet weather
- Temperatures between 75 and 86°F (24-30°C)
How to Prevent Tomato Buckeye Rot
- Improve soil drainage: Amend clay soil with organic matter to improve water flow.
- Reduce soil compaction: Avoid walking or driving on garden soil when it’s wet.
- Disinfect heavily infested soils: Use soil fumigation to kill the Phytophthora fungus.
- Plant in raised beds: This elevates the plants and improves drainage.
- Prevent tomato to soil contact: Use stakes, trellises, or mulch to keep the fruit off the ground.
- Practice crop rotation: Change the location of tomato plants in your garden each year.
How to Treat Tomato Buckeye Rot
- Apply fungicides: Use fungicides containing chlorothalonil, maneb, mancozeb, or metalaxyl as their active ingredient. Follow the manufacturer’s instructions carefully.
- Remove infected fruit: Cut off and discard any tomatoes showing symptoms of buckeye rot. This will help prevent the disease from spreading.
- Keep the garden clean: Remove fallen leaves and other plant debris, where the fungus can survive.
Additional Tips
- Choose tomato varieties that are resistant to buckeye rot.
- Water tomatoes at the base of the plants, avoiding overhead watering.
- Avoid overwatering, as this creates ideal conditions for the fungus to thrive.
- Inspect plants regularly for signs of buckeye rot and take prompt action to prevent its spread.
By following these strategies, you can effectively prevent and control tomato buckeye rot, ensuring a healthy and productive tomato harvest.
