Articles
EVALUATION OF SPONTANEOUS PLUM POX VIRUS INFECTION OF PLUM AND PRUNE VARIETIES
The new plum and prune collection of the Dresden-Pillnitz Fruit Genebank has been evaluated for sharka-tolerance.
This has provided valuable information on the merits of potential parents.
Because or the intense sharka inoculation pressure, the Pillnitz collection is well suited under a normal spray regime for such tests.
Natural infection on leaves and fruit was measured over eight years on some 163 cultivars and breeding clones.
The very few resistant types included: McLaughlin, Opal, Oullins, Scoldus and some P. cerasifera hybrids from Moldova and the Crimea.
The types with little infection were: Gräfin Cosel (Pillnitz selection), Blue Fre, Bühler Frühzwetsche, Cacanska Naibolia, Czar, Nancymirabelle (P. insititia), Stanley, Valor and some P. cerasifera clones ("Alytschij") from Moldova and the Crimea.
The best of the aforesaid are worth considering for use in breeding.
In contrast, clones of Hauspflaume (German Prune) were among the most susceptible cultivars.
Results from natural infection in the field over eight years correspond resonably well with results from artifical inoculation tests reported by other authors.
Some of the deviations may have been due to the use of different cultivar clones and/or to variation in the distribution of virus strains.