Distribution (Phytophthora)

• Both P. cactorum and P. syringae are responsible for fruit rot.
• P. cactorum is often responsible for rotting of fruit in summer and in warm climates, being favoured by warmer temperatures.
• P. syringae generally causes rotting in northern apple growing regions and, in the UK, is mainly responsible for rotting in store.
• P. syringae is favoured by cooler temperatures.
• Phytophthora fruit rot is reported in most parts of the world where apples are produced.
• Its relative importance is dependent on the incidence of rainfall pre-harvest.