EUTYPA DIEBACK OF APRICOT

Since the time of the First International Symposium on Apricots and Apricot Culture at Perpignan 24 years ago, much has been written about the symptomatology and diagnosis of Eutypa dieback disease.
I believe that diagnosis of the pathogen, or pathogens, in each case of dieback, is no longer a difficult problem for the experienced pathologist and I do not intend to discuss this aspect because the published literature already contains sufficient information.
Today, I prefer to speak about some information arising from my recent research on Eutypa dieback in collaboration with colleagues in Switzerland and Greece.

First – a few words about nomenclature of the pathogen.
It is surely an accident of history whereby the causal agent of Eutypa dieback was first diagnosed in Australia at a time when the cultivation of apricots in our country had been in progress for little more than a century: perhaps for 150 years.

The original diagnosis of the fungus which causes this disease was made by Samuel in Australia in about 1930. Samuel, and several other mycologists who cultured the mycelium from diseased branches of apricot trees during the next 25 years, called it Cytosporina: it was known only as the anamorph.
Of interest to us now is the fact that this name – Cytosporina – must give place to another name which has priority in mycological literature: Libertella blepharis.

Libertella blepharis is of special interest in Hungary and Austria because it has recently been diagnosed as the causal agent of a severe cancer disease of apple trees, especially cv.
McIntosh.
Comparative morphological studies, and pathogenicity tests, by Bolay in Switzerland have shown conclusively that Libertella blepharis is identical with Cytosporina.
L.

VIII International Symposium on Apricot Culture and Decline

M.V. Carter

https://doi.org/10.17660/ActaHortic.1986.192.33