Leaf spots of early blight are circular, up to 1 cm in diameter, brown, and often show a circular pattern which distinguishes this disease from other leaf spots. Early blight thrives best under warm wet conditions. Leaf spots first appear on the oldest leaves and progress upward on the plant. Entire plant could be defoliated and killed.
Controlling early blight once it has established is very difficult. The most important way of controlling early blight is attempting to prevent its establishment and further spread.
- Rotating with other crops like amaranth is essential. Do not rotate with tomato, potato or peppers as these belong to the same family and susceptible to the same diseases.
- In areas with a high humidity, wider plant spacing should be used.
- Practice good field hygiene. Remove infected leaves during the growing season discard all badly infected plant debris at the end of each season.
- Use certified disease-free seeds
- When using own seeds, use hot water to treat the seeds. For more information on Hot-water treatment click here