Abstract:

Pepper plants showing chlorotic and necrotic rings symptoms on the leaves reminiscent of
infection by tospoviruses were found in pepper-production fields of Guangdong in 2014. The infected
samples were detected by Dot-ELISA and RT-PCR，respectively. Negative results were obtained in the
Dot-ELISA with monoclonal antibody of Tomato spotted wilt virus（TSWV）. This result indicated that the
virus isolate didn’t belong to TSWV. However，an expected approximately 800 bp-fragment were obtained
from all infected pepper samples by RT-PCR using the universal primer pair gL3637/gL4435C for
tospoviruses. The results of gene cloning and sequence analysis showed that the fragment shared the
highest identity at 97.5% with corresponding parts of the Guangzhou isolate of Watermelon silver mottle
virus（WSMoV）. Phylogenic analysis showed that the virus isolate infecting pepper in Guangdong is most
closely related to the reported isolates of WSMoV，and that they clustered in a monophyletic group.
Therefore，the virus isolate infecting pepper in Guangdong is an isolate of WSMoV.

Key words: pepper, Watermelon silver mottle virus, molecular identification