ANTHRACNOSE – AN EMERGING DISEASE ON SWEET CHERRY

There are very few available reports on anthracnose (bitter rot) in sweet cherry (Prunus avium L.), and the disease has only been described as severe in Switzerland, Hungary and Norway.
We have found buds to be a very important host for the fungus causing anthracnose, Colletotrichum acutatum. The number of infected buds is normally much higher on fruit spurs (mostly generative buds) compared to buds on vegetative shoots.
During late spring and summer, the fungus is present (often causing no visible symptoms) on leaves and fruits (both on normally developing and non-abscised aborted fruits). High quantities of aborted fruits may be infected by the fungus and are a likely inoculum source during the green fruit stage.
Sweet cherries are susceptible to the pathogen at all developmental stages, but green fruits seem very important to protect.
Based on today’s knowledge, the recommended strategy against anthracnose is to spray twice at the green fruit stage with dithianon and to avoid build-up of inoculum by removing infested plant material from the orchards.

V International Cherry Symposium

J. Børve, A. Stensvand

Colletotrichum acutatum, Prunus avium, dithianon, inoculum sources

https://doi.org/10.17660/ActaHortic.2008.795.146