Abstract:

This research aims at identifying the currently prevailing viruses infecting Hami melon in Xinjiang and their genetic variations for providing scientific basis to prevent these virus diseases. Field survey was conducted in Turpan，Shanshan and Changji and samples with viral symptoms were collected for the lab tests. Both DAS-ELISA and RT-PCR were applied for the detection and molecular identification of 7 common viruses as well as Cucumber green mottle mosaic virus（CGMMV）the important quarantine virus infecting Hami melon. The results showed that the detection rates of Cucumber mosaic virus（CMV），Watermelon mosaic virus（WMV），Zucchini yellow mosaic virus（ZYMV），and Melon necrotic spot virus（MNSV）amongst the 121 detected samples were 70.2%，62.0%，37.2%，and 2.5% respectively，whereas Squash mosaic virus （SqMV），Papaya ring spot virus（PRSV），CGMMV and Tobacco necrosis virus（TNV）had not detected as positive. CMV，WMV and ZYMV are widely distributed in the field. Mixed infection with two or three different viruses on the same individual host was common with an occurrence of 60.19%. Based on the CP gene amplification，sequencing and phylogenetic analysis，CMV isolates from Hami melon in Xinjiang were categorized into subgroupⅠB. Although WMV，ZYMV and MNSV had high homology with other reported strains in CP gene nucleotide sequence，there were still some variations. ZYMV and WMV had a significant geographical differentiation.

Key words: Hami melon, virus, RT-PCR, mixed infection, genetic variation