DISTRIBUTION OF EUROPEAN STONE FRUIT YELLOWS PHYTOPLASMA IN APRICOT TREES IN WESTERN SWITZERLAND

A severe decline of new varieties of apricot has been observed in Valais region situated in western Switzerland.
In a preliminary evaluation, European stone fruit yellows (ESFY) phytoplasma was found to be associated to the decline.
A broader epidemiological survey was therefore conducted during August 2001 by PCR-based testing of leaf samples from 212 representative trees.
The majority of the trees were of the most common traditional variety Luizet.
Some other varieties and wild Prunus were also included.
Most samples were from trees with symptoms typical of Apricot chlorotic leaf roll (ACLR) (leaf roll, chlorotic leaf, early fruit falling, dieback) but samples from trees without symptoms were also tested.
This evaluation revealed the presence of ESFY in over 74% of the samples from all the surveyed areas.
The correlation between symptoms and the presence of ESFY was high.
The broad distribution of ESFY, in spite of the relatively mild damages in the traditional Luizet orchards, points out a certain tolerance of this variety to ACLR and implies adaptation of the control measures.

XIX International Symposium on Virus and Virus-like Diseases of Temperate Fruit Crops – Fruit Tree Diseases

M. Genini, M.E. Ramel

Phytoplasma, Apricot chlorotic leaf roll disease, European stone fruit yellows, PCR

https://doi.org/10.17660/ActaHortic.2004.657.73