PRESENCE OF SHARKA DISEASE IN THE NORTH-HUNGARIAN COUNTIES

Abstract

In the concerned region, such as Hungary Plum pox virus (PPV) causes the most serious yield loss in the stone fruit orchards. A survey of sharka disease was conducted in the north-Hungarian border region from 2010 to 2012. The main goals of the survey were to isolate the virus, to map the spreading and the actual status, to identify the PPV strains and inform the orchard owners and manufacturers about the results of the study. This survey was a part of the Hungary-Slovakia Cross-Border Co-operation Programme 2007-2012. Nearly 250 leaf samples were taken from 51 different settlements of the northern counties from stone fruit orchards, home gardens and natural environment, showing the symptoms of PPV. The surveyed species were plum, apricot, peach, sweet and sour cherry, and blackthorn. To identify the strains the following molecular methods were used: conventional RT-PCR with strain-specific primers, RT-PCR followed by RFLP analysis using EcoRI, DdeI and EcoRV restriction enzymes in the 3’P3-6K1-5’CI genomic region and RT-PCR followed by sequence analysis in the formerly mentioned region. The results show that the dominant strains were PPV-Rec in the central and PPV-D in the eastern region, but PPV-M was also identified. The apricot and peach orchards were less infected than plum orchards in the northern counties of Hungary. A suspected triple-mixed infection (M, D and Rec) is under further studies. After the survey a map was prepared, the dominant isolates, the infection rate, the host plants and the type of the sample collection places were marked. From the results a bilingual booklet was also published with the great help of the Slovak partners, for producers and orchard owners including all important knowledge about the virus and the disease prevention.