Early Blight of Potato

1. This disease is more common than late blight and causes about 20-30 % damage to crop every year.
2. It can occur anywhere at any crop period.

 

Causal Organism: Alternaria solani 

 

Symptoms:

1. The spots of this disease on the leaves are brown to black with concentric rings.
2. These spots are in numerous numbers and are scattered all over the leaves.
3. Heavily infested leaves fall off after drying.
4. Spots also appear on stems.

                  

Control Strategies:

·         Plant disease-free seed

·         Maintain good soil fertility and crop vigor

·         Harvest when skin is mature to avoid bruising and in turn infection of tubers

• Crop debris should invariably be destroyed by burning after harvest.

·         Avoid continuous potato rotations (i.e. planting potatoes in subsequent years in the same field)

•  Spray Mancozeb + urea solution i.e. at the rate of 2 g Mancozeb 75 WP + 10 g urea per litre of water at 15 days interval when symptoms start.