Spray stain disease
The leaf spot is a disease of wild cherry ( Prunus avium ) caused by the ascomycete Blumeriella jaapii is triggered. In addition to the bird cherry, other Prunus species are also attacked, but the spray spot disease causes the greatest damage in sour cherries .
description
The fungus overwinters in infested fallen leaves . Infection by ascospores occurs after flowering, when temperatures have risen to over 15 ° C. Optimal infestation conditions are persistent leaf wetness with high humidity. From May onwards, purple to dark gray spots appear on the surface of the leaves. Small, yellowish-white spore beds appear on the underside .
As the disease progresses, the spots fuse together, creating frayed holes.
Infested leaves are thrown off prematurely. If the infestation occurs early, great damage can be caused to sour cherries due to premature leaf fall.
A treatment strategy comprises the early control with fungicides such as dithianon , fluopyram , myclobutanil , pyraclostrobin + boscalid , azoxystrobin or difenoconazole and removal of infested foliage.
literature
- U. Harzer, D. Metzlaff, A. Orth: Recommended products and notes on plant protection in stone fruit 2015 . In: fruit growing . No. 2 , 2015, p. 90 .
Web links
- Spray spot disease on cherry at ARBOFUX
- Spray stain in the Hortipendium
- Blumeriella jaapii for woody diseases in words and pictures