Abstract: 【Objective】The analysis of virus genome is based on nucleic acid isolation. The aim of this study was to develop the method of isolation and identification of virus dsRNA and elucidate the nucleotide sequences of strawberry virus. 【Method】Using the modified method, the virus dsRNA was extracted from strawberry virus indicator plants and cultivated strawberry plants, and detected by employing agarose gel electrophoresis of EtBr staining and reverse transcription-polymerase chain reaction (RT-PCR). 【Result】The quantity of virus dsRNA was different among strawberry cultivars. The quantity of dsRNA in microplants was higher than in the young leaves of field plants. And for the field plants, there was more dsRNA in the young leaves. The dsRNA was resistant to DNaseⅠ, but it became evidently resistant to RNase A only in the presence of 0.5 mol·L-1 NaCl. The dsRNA in agarose gel could be availably recycled with agarose gel DNA purification kit. The segments of both strawberry mottle virus (SMoV) and strawberry mild yellow edge virus (SMYEV) were amplified by RT-PCR from the virus dsRNA recycled from gel or treated with DNase Ⅰ/RNase A. 【Conclusion】The system of isolation and identification of dsRNA in strawberry plants was developed, which is the base for the genome analysis of strawberry virus isolations in China.

Key words: Strawberry, dsRNA, Virus, Isolation, RT-PCR