Abstract: The 67 squash samples with viral symptoms collected from seven squash-growing counties in Chongqing were detected by antigen–coated plate (ACP)-ELISA with antibodies against seven plant viruses. The results showed that at least 59 samples with in these 67 squash samples were infected by the
viruses, of which 80.60%、77.61%、70.15%、82.09%、76.12%、83.58% and 55.22% of the samples were infected by Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV), Tomato mosaic virus (ToMV), Turnip mosaic virus (TuMV), Broad bean wilt virus 2 (BBWV-2), Potato virus Y (PVY) and Potato virus X (PVX), respectively. Among 59 positive samples, 93.22% of the samples were mix–infected with more than two viruses, and about 60% samples were mix-infected by the above seven viruses, indicating the mix406 infections of viruses on squash were severely. Moreover, the results showed that among 54 amples infected by CMV，49（90.74%）samples were infected by CMV subgroupⅠ（CMVⅠ）and 12（22.22%）samples by CMV subgroup. Comparison of the nucleotide sequences showed that it has the highest identity（98.1%） with the previously reported CMVⅠisolate infecting Phaseolus angularis（CMV-RB）from China.

Key words: squash virus diseases, ELISA detection, CMV subgroups, CP sequence variation