The Genetic Characterization of Lake Sinai Virus in Colony Losses Apiaries in Türkiye

Objective: Honeybees (Apis mellifera) have a unique role in natural pollination and maintaining biodiversity in the ecosystem. The alarming increase in unexpected colony losses, mysterious bee deaths, and the tragic extinction of entire colonies (Colony collapsed disorder- CCD) have sounded a global alarm, demanding immediate attention and collaborative action to address these critical challenges in bee breeding. Diseases, parasites, and pathogens significantly threaten colony health. Türkiye is a significant honey producer, providing an ideal environment for beekeeping due to its unique eco-geographical features. Unexpected colony losses and bee deaths are also questions of concern for beekeepers in Türkiye. Material Method: In this study investigated honey bee viruses in apiaries experiencing sudden bee death losses and CCD-like symptoms between 2021 and 2023 in Türkiye, involving genetic analysis of the LSV RdRp gene region. The honeybee and varroa samples were obtained from 52 colonies in 26 apiaries complaining of unexpected bee deaths and CCD-like symptoms between May 2021 and September 2023. Result: The results showed a high DWV, BQCV, and LSV prevalence, respectively. The sampled apiaries were infested mild-moderate- high grade with Varroa mites. Following PCR results, DWV, BQCV, LSV, IAPV, CBPV, and SBV positivity was detected at 69.2% (n=18), 50% (n=13), 38.46% (n=10), 26.9% (n=7), 19.2% (n=5) and 3.8% (n=1), respectively. High rates of multiple virus coexisting and high varroa infestation were noted in colonies with heavy losses and CCD-like complaints. The RdRp gene from two LSV samples (TrLSV-6474, TrLSV-6517) was sequenced. Turkish LSV samples (TrLSVs) showed a 72.88% homology of each other and clustered LSV4 branches in the phylogenetic tree. Turkish LSV sequences showed a closer similarity rate than reference sequences in GenBank with Asian Korean, Chinese, and Japanese LSV sequences. Conclusion: Further investigation is needed to comprehend the implications of elevated LSV populations on colony losses. The execution of genetic research with a more extensive sample size can significantly enhance the demonstration of species diversity and provide valuable insights into the influence of LSV variants on honeybee health and the management of diseases.