Early Blight Potato diseas
(Alternaria solani) Early blight or Alternaria blight is worldwide in distribution and is one of the most important potato foliage diseases in areas with favourable weather conditions.
Symptoms of Early Blight Brown, angular, necrotic spots marked internally by a series of concentric rings form on leaves and to a lesser extent on stems.
Leaf lesions are seldom circular because they are restricted by the larger leaf veins. Lesions usually develop around flowering time and become increasingly numerous as plants mature. Lesions first form on lower leaves.
They may join and cause general yellowing, leaf drop, or early death. Tuber rot is dark colour, dry, and leathery.
Susceptible varieties of potatoes (usually early maturing) may show severe defoliation. Later maturing varieties may appear resistant.
Potato plants under stresses that hasten maturity (such as adverse environment, warm, humid weather, other diseases, or nutritional deficiency) become susceptible and die prematurely. Management Provide conditions for vigorous growth throughout the season, especially irrigation and fertilizer side dressing.
Organic fungicides sprayed on the foliage reduce the spread of early blight. Resistance is available among late-maturing varieties.
