关键词: 芋, 芋花叶病毒, RT-PCR, 外壳蛋白基因, 序列分析芋花叶病毒, RT-PCR, 外壳蛋白基因, 序列分析

Abstract: Reverse transcription PCR（RT-PCR）was used for the detection of Dasheen mosaic virus（DsMV）in taro[Colocasia esculenta（L.）Schott] from Hubei，Zhejiang and Shandong Provinces. Results revealed that the average viral infection frequency in 91 collected taro samples was 26.4%. RT-PCR products of 317 bp（covering partial coat protein gene）from 14 isolates were sequenced. Results showed that the obtained sequences had high intra-isolate nucleotide similarities，but inter-isolate nucleotide similarities were varied from 68.3% to 97.8%. The cp genes of two DsMV isolates named DsMV-SCS and DsMV-JH were sequenced，and their sizes were 951 bp and 987 bp，respectively. Their cp genes shared similarities of 79.0% at nucleotide（nt）level and 82.3% at amino acid（aa）level to each other and similarities of 73.0%–92.1% at nt level and 74.8%–98.2% at aa level to reported cp sequences of DsMV，respectively. The phylogenetic trees constructed based on nucleotide and deduced amino acid sequences of the cp of DsMV showed that isolates DsMV-SCS and DsMV-JH clustered into two different groups. There was no obvious correlation between phylogenetic positions and host or geographical origins of different DsMV isolates.

Key words: taro, Dasheen mosaic virus, RT-PCR, coat protein gene, sequence analysis