Stone Fruit
Peaches are susceptible to a wide range of diseases, silverleaf (Chondrostereum purpureum), bacterial canker (Pseudomonas syringae) and armillaria can all lead to tree death. Viruses include yellow bud mosaic, Prunus ringspot and peach yellow leaf roll. All reduce tree productivity and fruit quality.
Nectarines in particular are prone to cracking if rain falls close to maturity.
Silverleaf (Chondrostereum purpureum), bacterial canker (Pseudomonas syringae) are serious plum diseases in many countries. Blossom blast and brown rot at maturity are difficult to control in wetter climates. Plumpox virus (sharka) is a major limiting factor in Europe and the industry has quarantine measures in place to prevent its spread outside affected regions.
European plums tend to suffer less pest damage than other stone fruits, however, cutworms and leafrollers can damage leaves and fruit.
Some cultivars – e.g. Tilton are susceptible to biennial flowering. Correct nutrition, early thinning, and pruning to encourage new wood help minimize this. Pests and diseases can easily damage skin and any spotting reduces crop values. Spotting or speckling can be caused by early attacks of blossom blast, red mite, shot hole and bacterial blight. Powdery mildew can also mark fruit. Brown rot causes fruit loss and needs to be controlled using fungicides applied at blossom time. The crop is also susceptible to damage from a range of insects and mites.
Excessive pruning can leave the tree more vulnerable to gummosis (Pseudomonas syringae).
Cherries are particularly attractive fruit for birds and netting is commonplace. Crops also suffer from difficult to control diseases such as cherry leaf spot (Blumeriella jaapi) and bacterial blast / bacterial canker (Pseudomonas syringae). Pre-harvest fungicides are particularly important to minimize disease which can disfigure the fruit. Fruit fly, aphids, cherry slugs and leafrollers are all key pests.
Asia and Oceania