Abstract: 【Aim】 This study aims to analyze the genetic characteristics of sacbrooe virus (SBV) isolated from Apis cerana cerana in Chongqing, southwestern China (AcSBV-S.Chn-CQ). 【Methods】 The polyprotein gene of SBV was amplified by RT-PCR from samples of A. c. cerana  larvae infected with SBV, which originated from 23 districts or counties in Chongqing, sequenced and analyzed. Phylogenetic trees were constructed using neighbor-joining method based on SBV genome, and the genomic region SB11-SB12. RDP3 was used to detect the genetic recombination. 【Results】 AcSBV-S.Chn-CQ showed high homologies with other SBV isolates from  A. c. cerana in South China (AcSBV-S.Chn), the SBV infecting  A. cerana and A. mellifera in North Vietnam (AcSBV-N.Vie and AmSBV-N.Vie) and the SBV infecting A. cerana in South Korea (AcSBV-S.Kor). AcSBV-S.Chn-CQ has a consecutive 51-nucleotide deletion along the structural protein-coding region and an inconsecutive 3-nucleotide deletion along the nonstructural protein-coding region, and its nucleotide deletion is identical to those of AcSBV-N.Vie, AmSBV-N.Vie and AcSBV-S.Kor. AcSBV-S.Chn-CQ, AcSBV-S.Chn-FZ, AcSBV-N.Vie, AmSBV-N.Vie and AcSBV-S.Kor formed a subtype within the Asian genotype, and recombination events were detected in the isolates within this subtype. 【Conclusion】 AcSBV-S.Chn-CQ, SBV-N.Vie and AcSBV-S.Kor may share a common origin.

Key words: Apis cerana cerana, sacbrood virus (SBV), polyprotein gene, nucleotide deletion, phylogeny