Early blight is a common and damaging disease affecting potato crops worldwide. Caused by the fungus Alternaria solani, it can also impact other plants in the potato family, such as tomato and even some mustard crops. Early blight primarily targets the leaves and stems, particularly on mature plants. Under warm and humid conditions, the disease can spread rapidly, causing considerable yield losses. This blog will explain what early blight is, its symptoms, favourable environmental conditions, and effective control measures. It will focus on timely practices and essential fungicide applications to help farmers protect their crops and improve yields.
What is Early Blight in Potato?
Early blight is a fungal disease found in solanaceous plants like potatoes and tomatoes, caused by the pathogen Alternaria solani, commonly referred to as "target spot." The disease usually starts on older leaves and can affect plants at any growth stage. It is known for its distinct circular spots, which cause leaves to turn yellow and die over time, especially on the lower parts of the plant.
Overview of Early Blight of Potato
Type of Infestation |
Fungal Disease |
Common Name |
Early Blight |
Causal Organism |
Alternaria solani |
Affected Parts of the Plant |
Primarily leaves, stems |
Favourable Conditions for Early Blight in Potato
Early blight thrives under warm temperatures and high humidity, particularly during wet weather conditions. High humidity or frequent leaf wetness promotes the spread and severity of the disease, making regular monitoring essential in such environments. Stress factors, such as nutrient deficiencies or drought, can also make plants more susceptible to early blight.
Early Blight in Potato Symptoms
Early blight starts as small, dark spots on the older leaves. These spots grow into larger, brown-to-black, circular or oval areas with distinct, concentric rings that give a “target” appearance. The characteristic symptoms of early blight are as follows:
- Leaf Spots: Small, dark flecks develop into larger spots with concentric rings, bordered by veins that make them angular in shape.
- Yellowing Leaves: Surrounding the spots, a yellow or greenish-yellow ring often forms as the disease progresses.
- Leaf Death: Infected leaves, especially on the lower parts of the plant, eventually turn yellow, dry up, and die but often remain attached.
- Stem Spots: Dark brown to black lesions can appear on the stems, further stressing the plant.
Measures to Control Early Blight in Potato
By using the right fungicides to control early blight, farmers can protect their potato crops and increase their yield
Recommended Fungicides |
Technical Name |
Dosage |
Mancozeb 40% + Azoxystrobin 7% OS |
625ml/acre |
|
Azoxystrobin 11% + Tebuconazole 18.3% SC |
300ml/acre |
|
CARBENDAZIM 12% + MANCOZEB 63% WP |
700gm/acre |
|
Copper Oxychloride 50% WP |
1000ml/acre |
|
Azoxystrobin 18.2 % + difenoconazole 11.4 % SC |
200ml/acre |
Conclusion
Early blight poses a serious risk to potato crops, but with early detection and the use of effective fungicides, farmers can limit its impact and protect yields. By monitoring environmental conditions, recognizing symptoms, and applying fungicides like Chatur Mancozeb 40% + Azoxystrobin 7% OS, Dr. Zole Azoxystrobin 11% + Tebuconazole 18.3% SC, or Azozole Azoxystrobin 18.2 % + difenoconazole 11.4 % SC as needed, potato growers can manage early blight effectively and ensure healthier, more productive crops.
FAQs related to Early Blight of Potato
Q. What is early blight of potato?
A fungal disease affecting potato leaves and stems, caused by Alternaria solani.
Q. What are early blight symptoms?
A. Dark, circular leaf spots with concentric rings; yellowing and drying of lower leaves; stem lesions.
Q. What conditions favor early blight?
A. Warm, humid, and wet weather, with high humidity and leaf wetness.
Q. What is the best fungicide for early blight in potato?
A. The Best Fungicides for Early Blight in Potato is Chatur, Dr. Zole, Samartha, COC 50, and Azozole.
Q. How to control early blight of potato ?
A. Monitor regularly, apply fungicides, and avoid plant stress from nutrient deficiencies or drought.