Eventually the infected leaves fall from the tree. Symptoms of leaf distortion caused by the fungus, Taphrina deformans When trees are severely infected by the fungus, peach fruit can also become susceptible. Infected fruit exhibit distorted, warty growths on the surface and will usually abort. Disease Cycle Spores of the leaf curl fungus overwinter on the surface of peach twigs. In spring, the spores multiply during periods of moist weather until the leaf buds swell and open.
Rain is necessary for infection.
The spores are carried on a film of water into the buds, where leaves are infected. Cool, wet weather slows leaf development and allows more time for leaf curl infection. Infection occurs readily at 50 to 70 degrees F. Dry weather during bud swell and bud break limits leaf curl infection. After the deformed and discolored leaves turn brown and fall, they produce powdery gray spores. These are blown by winds to peach twig surfaces and remain there for the winter.