Sharka Disease in Bulgaria: Past, Present and Future

Abstract

This review is an attempt to synthesize almost 70 years investigations of Sharka disease in Bulgaria. The results obtained from first virus discovery, disease dissemination throughout stone fruit growing regions, present virus incidence on different Prunus species, natural hosts of the virus, virus detection, strain characterization, susceptibility of plum, peach and apricot cultivars to Sharka disease and virus control measures applied in the past and today are presented.

Sugars and organic acids in plum fruit affected by Plum pox virus

“…Milosevic et al reported about 50% fruit drop of ‘Čačanska rodna’ infected trees. Even higher (80–100%) fruit drop was observed in ‘Kyustendilska sinja sliva’ . Much higher fruit drop was observed in a long‐time infected tree than in a short‐time infected tree.…”

“…Even higher (80-100%) fruit drop was observed in 'Kyustendilska sinja sliva'. 8 Much higher fruit drop was observed in a long-time infected tree than in a short-time infected tree. Based on this finding, it can be concluded that fruit drop increases with duration of infection.…”

“…The disease symptoms are dependent also on environmental conditions . Fruit may ripen and drop prematurely …”

“…2,3 Fruit may ripen and drop prematurely. 1,2,8 Plum cultivars vary in their susceptibility to sharka. One of the most susceptible cultivars is 'Požegača', an old cultivar still widespread in central and south-eastern Europe.…”

Sensitivity of field tests, serological and molecular techniques for Plum Pox Virus detection in various tissues

“…Similar results were obtained with samples collected from plum 'Katinka' growing in the same garden. 'Katinka' is considered to be resistant by its breeders (Hartman, 1999), but has shown to be very susceptible to PPV-M by Kamenova and Milusheva (2005). In Maribor, PPV could be detected only in stalks using real time PCR (Table 2), but the Ct value was very low indicating a low concentration of the virus.…”