Hi Denis, it has been a bad season for fungal diseases such as brown rot, with warm, wet, humid weather. A regular spray programme throughout the year is helpful using a copper based spray along with a horticultural spraying oil. Spraying with copper won’t stop or cure brown rot, but will help prevent it spreading. There are curative sprays, talk to your local garden centre for a spray to suit your situation. There are cultural practices that will help prevent the spread of disease, collect up fallen and infected fruit, leaves and tree pruning’s as the fungal spores overwinter in the soil, dispose of in the rubbish or burn, do not compost to prevent disease spreading each year. Improve air circulation around the tree, thin out criss-crossing branches and spindly weak growth. Regular watering, feeding and mulching will help keep the trees actively growing and so have better resistance to pests and diseases. Something worth trying is Apple Cider Vinegar and botanical spraying oil, mix 1 cup of apple cider vinegar to 5 litres of water, mix with spraying oil as per pack directions for 5 litres of water, it is safe to mix the two together. Spray every 7-14 days throughout the growing season, and  throughout the year less frequently. The apple cider vinegar changes the pH on the leaf surface so fungal spores do not find ideal conditions to multiply and so they are kept at bay. It may be that you need to go for a curative spray to start with and then maintain with a copper based spray.

Lianne