Abstract: In this study，the pathogen of radish virus disease in Changsha was identified by small RNA deep sequencing technology，and specific primers were further designed to detect and verify the pathogen by reverse transcription PCR. Further，60 core germplasms were identified by artificial inoculation at the seedling stage，and then all were subjected to RT-PCR detection and phenotypic resistance identification. The results showed that the radishes in this area were infected by a combination of four viral diseases，namely turnip mosaic virus（TuMV），Brassica napus RNA virus 1（BnRV1），Brassica yellows virus（BrYV），Raphanus sativus cryptic virus 3（RasCV3）. BnRV1 was detected in radishes for the first time. One high resistance and one disease resistance accession was selected according to the phenotype identification. The specific bands of TuMV，BnRV1，BrYV and RasCV3 were abtained by RT-PCR with specific primers in 60 core germplasms，indicating that all the tested accessions were infected by these four pathogens. TuMV is the main pathogen，and the detection rate is 100%. The composite infection rate of two or more pathogens was 83.33%.

Key words: radish, virus disease, small RNA sequencing, resistance identification