Alternaria fruit spot/ Heart rot/ Black heart
Pathogen: Alternaria alternate
Symptoms
Small reddish brown circular spots appear on the fruits. As the disease advances these spots, coalesce to form larger patches and the fruits start rotting. The fruits get affected which become pale and become unfit for consumption.
Disease development
At the beginning of disease development, the fungus causes brown soft rot of the arils, which becomes black and dry as the fungus grows. Eventually, the fungus grows from the lower loculus into the upper loculi, causing rot of the entire fruit.
Control
All the affected fruits should be collected and destroyed.Spraying Mancozeb (0.25%) or Dithane M- 45 (0.25%) or Captaf (0.25%) effectively controls the disease.