英文摘要 |
"A begonia (Begonia semperflorens) potted plant with chlorotic ringspot symptoms on leaves was found in Taichung. When the ringspot symptoms severely developed, lots of ringspots would tend to fuse into a chlorotic region. Mechanical inoculation with this sample on Chenopodium quinoa, numerous chlorotic local lesions appeared after 7-10 days. Back inoculation of this virus isolate to healthy begonia induced chlorotic ringspot symptoms on new leaves similar to those formed on original diseased plant after 14 days. Electronic microscopy techniques were used to identify the causal agent of this symptom, and flexuous virus particles with 750 × 13 nm in length were observed. Subsequent ELISA and western blotting studies revealed that this virus isolate was serologically related to Zucchini yellow mosaic virus (ZYMV). Western blotting results also showed that coat protein of the causal virus is similar to ZYMV in their molecular weight of 33 kDa. Based on these findings, we recognized the causal virus of begonia ringspot symptom was an isolate of ZYMV and hence designated it as ZYMV-Bego. Host range test and symptom comparison between ZYMV-Bego and ZYMV-TW-TN3 showed that ZYMV-Bego is probably a mild strain of ZYMV. ZYMV primers designed based on known sequences of ZYMV-SG were used to sequence the genome of ZYMV-Bego (Acce. No. AM422386). Based on the alignment results, this virus was confirmed as a ZYMV isolate that is similar to ZYMV-TW-TN3 and ZYMV-SG which were found in Asia. In brief, this study provided evidence showing ZYMV was able to induce ringspot symptoms on begonia, representing a new host record for ZYMV." |