Late Blight disease

• In a full-blown attack by the late blight disease attack on potato crop, more than 50% crop in the fields has suffered extensive damage leading to heavy losses for the farmers in Punjab who had opted for diversification instead of growing wheat after paddy.

ABOUT LATE BLIGHT DISEASES

• It is a fungal disease caused by the fungus Phytophthora infestans that can damage the entire crop.
• Air borne infection is caused by the sporangia.
• The primary host is potato, but P. infestans also can infect other solanaceous plants, including tomatoes, petunias
• These infected species can act as source of inoculum to potato.
• Late blight is considered a community disease since sporangia from one field may spread to adjacent fields left untreated posing a threat to neighboring growers.
• It affects leaves, stems and tubers of crop.
• Symptoms
  • The first symptoms of late blight appear as small, light to dark green, circular to irregular-shaped water-soaked spots.
  • During cool, moist weather, these lesions expand rapidly into large, dark brown or black lesions, often appearing greasy.
  • A pale green to yellow border often surrounds the lesions.