Symptoms :

• Minute, brown or rust-coloured unbroken, circular, necrotic areas appear on the fruit which later tear the epidermis open in a circinate manner.
• The margin of the affected area becomes raised.

Management:

• 1% Bordeaux mixture or lime-sulphur (1in 25) – 3 or 4 sprayings.
• PH wash with aureofungin (200ppm) can protect fruits for 5 days.
• The fruit rot can be checked by dip treatment of the fruits with aretan.

Image source:

http://farmer.gov.in/imagedefault/ipm/IPM%20pakcage%20for%20Guava.pdf