What is it ?
Dry eye rot, sometimes called blossom end rot, is caused by Botrytis cinerea on apples. The pathogen B. cinerea also causes grey mould in apples and pears in storage. In New Zealand, dry eye rot does not appear to develop into grey mould in stored fruit.

What does it look like ?
The eye rot infects the calyx end. At first it is a light brown, wet rot that may penetrate several millimetres into the apple tissue. Once it dries out, it stops growing and the area becomes sunken. The infected area now appears dark brown and often cracks. Overall the rot is 1-2 cm wide usually circling the calyx itself.

What conditions are needed ?
Fruit are infected at bloom, but the symptoms do not develop until close to harvest. Outbreaks of dry eye rot are more common following a wet spring.

Where is it found ?
Dry eye rot is found all over New Zealand. In recent years it has been found more frequently in Hawke's Bay, Nelson and Canterbury.

Why is it a problem ?
Dry eye rot in itself is not a major problem, although fruit with large lesions should be removed from export. Grey mould, which is caused by the same pathogen, enters via wounds including stem punctures and stem pulls.

In pears grey mould can spread from healthy to infected pears if the fruit are touching.

What are the current chemical controls ?
Growers concerned about dry eye rot could apply up to two Benlate sprays during flowering if there is a threat of prolonged wet weather. However, unnecessary applications of Benlate could lead to resistance as well as having an adverse effect on mite predators.

Are there any other forms of control ?
Good orchard hygiene is important. Remove any diseased fruit from the orchard.

References
Atkinson, J.D. 1971. Diseases of Fruit Trees in New Zealand. A.R. Shearer, Government Printer, Wellington, New Zealand.

Jones, A.L. and Aldwinkle, H.S. (eds). 1991. Compendium of Apple and Pear Diseases. The American Phytopathological Society, United States of America.

Source:
Written and submitted by Helen Percy.