Question
Hi Cathy, I wondered if you could help, this year the pears on my tree are all cracked all around the fruit, cracks 5or 6 cm wide,  any ideas or tips would be great
       Kind regards  Brian

Answer
Hi Brian... I have to be honest that I do not know allot about pears, but if they are like other fruit trees, not enough water would make them crack.  So I did a little checking and this is what I found..

Market Diseases of Apples, Pears, and Quinces
Star Crack
  
Star crack, a virus disease, develops on apples in Europe, the United States, Canada, and New Zealand. Symptoms vary widely, depending on the apple variety and perhaps the stage of development at which the fruits are affected. In England the disease occurs most frequently on Cox's Orange Pippin, causing little distortion of the fruits. On this variety the corky, star-shaped cracks, from which the disease is named, develop to some extent on the cheeks, but mainly on the calyx end of the fruits.
On Golden Delicious grown in the State of Washington, affected fruits are badly distorted, and the cracks may develop on any area (see photo). Varying amounts of rough, cork-like tissues may be found on the surf ace as a result of the healed cracks.

The disease must be controlled in the orchard by using virus-free bud and nursery stock. Consult your State agricultural extension service or experiment station.