Potato (Solanum tuberosum)

Early blight(Alternaria solani)

Symptoms

  • Potato blight, a common disease affecting potato plants, manifests through characteristic leaf spots and blight, occurring at any growth stage.
  • Primarily targeting leaves and tubers, the disease initially presents small circular to oval brown spots on older lower leaves.
  • These spots may expand into larger, angular lesions as the disease progresses.
  • Mature foliage lesions appear dry and papery, often exhibiting concentric rings resembling a bull's eye, with surrounding tissue potentially turning yellow.
  • High temperatures and humidity exacerbate the disease, potentially leading to significant foliage loss.
  • Stems may also display similar lesions, which could girdle the plant if near the soil line.
  • Tubers affected by the disease exhibit brown, circular to irregular, depressed lesions, with underlying flesh becoming dry, brown, and corky.
  • During storage, these lesions tend to enlarge, resulting in shriveled, affected tubers.

Management

  • Crop debris and other potential host plants should be collected and disposed of to prevent disease spread.
  • Ensure the use of disease-free tubers when planting crops.
  • Practice judicious fertilizer application to maintain plant health.
  • Provide irrigation during critical stages of crop growth.
  • Kufri Sindhuri variety exhibits good resistance to this disease in plains.
  • Prevent waterlogging to avoid favorable conditions for disease development.
  • Apply urea spray (1.0%) to the crop 45 days after sowing, followed by subsequent sprays 8-10 days apart, to help the crop resist severe early blight disease

Chemical Control

Sl.No Generic Name Trade Name Color code Dosage/litre Knapsack Sprayer (Capacity 10L) Recommendation Remarks
Dosage/acre (200 L) Dosage/hectare (500 L)
1 Copper oxychloride 50 WP Bensaan, Blitox, Blue copper, Bluetrox, Copter, Cupramar, Cuprina, Dhanucop, Fytolan, Fytox, Fytran, Fytolan, Hilcopper, Killex copper, Maincop Dhanucop, Star cop, Tagcop, Trucop Blue 2.5 g 25 g 500 g 1250 g
2 Mancozeb 75 WP Devidayal M-45, Dhanuka M 45, Dhanuka M-45, Dithane, Dithane M-45, Hilthane, Hindustan M 45, Indofil M 45, Izeb M-45 Manzate, Luzen-45, Macoban, Macoban M-45, Mancosaan, Mancosaan M-45, Maneb Manzane, M-Guard, Savour M 45, Tata M-45 Eurofil-NT, Uthane M-45, Veera, Zinthane Green 3 g 30 g 600 g 1500 g
Responsive image
Extremely Toxic
Responsive image
Highly Toxic
Responsive image
Moderately Toxic
Responsive image
Slightly Toxic