SHARKA RESISTANT PLUMS AND PRUNES BY UTILIZATION OF HYPERSENSITIVITY

Plum pox virus (PPV) is one of the most important virus diseases in fruit production.
Nearly all present PPV-resistant plum cultivars have quantitative resistance.
This resistance is only relative and not complete.
In warm, dry years the economic damage caused by PPV may be evident also on resistant varieties.
This situation is unsatisfactory and fruit breeders must find better resistance.
In the breeding material at Hohenheim, some hybrids display a hypersensitive reaction after infection with PPV. In extensive field tests with numerous cultivars only the hypersensitive hybrids were free of virus.
One hybrid is of special interest because of its high yield and good fruit quality.
In infection tests with some PPV strains, reaction varied depending on infection method.
This hypersensitive hybrid from a cross of ‘Ortenauer’ x ‘Stanley’ was named ‘Jojo’ and introduced as a new plum cultivar in the year 1999. The variety ‘Jojo’ has been used as a source of absolute resistance.
Seedlings from different crossings are in cultivation.

Eucarpia symposium on Fruit Breeding and Genetics

H. Kegler, S. Schwarz, E. Fuchs, M. Gruentzig

plum breeding, sharka resistance, hypersensitivity

https://doi.org/10.17660/ActaHortic.2000.538.69