Abstract

The identification of bee viruses is of great importance where there is no information on their natural occurrence in honeybee populations. Honeybee samples (Apis mellifera L.) obtained from Giza Governorate, Egypt were evaluated for total RNA from the head, thorax and abdomen, and varroa mites. Two fragments of 250 and 540 bp of deformed wing (DWV) and kakugo viruses (KV), respectively, were amplified using conventional real time-polymerase chain reaction (RT-PCR), and were sequenced and analyzed. All bee body parts resulted in a strongly positive DWV sequence except asymptomatic honeybee samples that were negative to the DWV infection. The analysis of varroa mite groups (n = 50) also revealed the presence of DWV which is the first report on this virus in Egypt. Homology search of DWV-PCR amplified fragments revealed 99 and 98% similarities with DWV isolate Warwick-2009 poly-protein gene (accession number: GU109335.1) and the Chilensis DWV isolate, respectively (accession number: JQ413340.1). Also, homology search of KV-PCR amplified fragments using the Genius program 7.1.2 revealed 97 and 90.0% similarities with the KV isolate_Ox genomic sequence (accession number: KC786224.1) and the DWV_Ox genomic sequence (accession number: KC786223.1), respectively. For this study data, a real-time SG RT-Qpcr was found as a fast, simple, sensitive and useful technique to detect and quantify low viral loads in honeybees and varroa mites.

Key words: Deformed wing virus (DWV), kakugo virus (KV), mite, real time-polymerase chain reaction (RT-PCR), Apis mellifera.