| Twenty-three isolates of 13 potyviruses and carlaviruses were detected from 40 diseased plant samples of 12 families by RT-PCR using the potyvirus or carlavirus specific degenerate primers (Sprimer/M4 or Pcarl(+)/M4), and it was found that complex infections of 2 viruses occurred in some tested plant samples.The complete nucleotide sequences (9592-9593nts) of 4 isolates (WG-BS, WM-BS, SG-BS, CU-BS) and the 3'-terminal partial sequences(1683-1684nts) of 4 others (S-.IP, S-XS, P and MM-BS) of zucchini yellow mosaic v/n/.v(ZYMV) were determined, and then were compared with other available sequences of this virus. Analysis of the coal protein sequences indicated that these ZYMV isolates fell into three significant groups, and all Chinese isolates (S-JP, WM-BS, MM-BS and S-XS) were very similar, consisted of group III and shared identities of 81.9%-87.3% (nucleolides) and 86.5%-92.8% (amino acids) with isolates of the other groups. It was the first report of the complete nucleotide sequences of the virus in China and of specific group of Chinese isolates.A potyvirus was detected in diseased Pinellia plant showing mosaic symptoms, and the 3'-terminal part (1733nts) of its genome was cloned and sequenced. Sequence analysis indicated that this virus was very similar to soybean mosaic virus(SMV). Its filamentous virus particles could infect soybean by sap mechanical inoculation, induced pinwheel inclusion bodies in infected plant cells and reacted strongly with an antiserum against SMV in ISEM. Therefore it was identified to be a strain of SMV.Lify symptomless virus (LSV) and lily mottle virus(LMoV) were detected in the diseased lily samples from Europe Sorbonne ( HZ2) by RT-PCR with genera-specific degenerate primers of Polyvius and Carlavirus., whereas only LSV was detected in musk lily of Hangzhou (L longirlorum) and introduced lily from Europe Sorbonne (HZ4) . Analysis of CP phylogenetic tree indicated that all available LMoV isolates clustered into two groups, and LMoV-HZ2 and LMoV-HZ belonged to the different groups. Sequence analysis of 3'-part of the genome showed that the three LSV Hangzhou isolates (LSV-HZ,-HZ2 and -IIZ4) shared high similarity (98.2-99.3%) each other, indicating that they might have same origin, but quite different to LSV Japanese isolate (D43801) and Korean isolate (AJ13812).Two potyviruses were detected by RT-PCR from the UK narcissus samples. Onewas Narcissus late season yellows virus( NLSYV) and the 3 ' -terminal 1668nts of its RNA was sequenced. It shared 72.1% identical nucleotides to that of PY-ZZ, a potyvirus detected from Chinese narcissus (Narcissus lazetla vat: chinensis) in Zhangzhou, Fujiang Province. Further sequence comparison indicated that these two viruses shared 75.5% (78.8%) identities of nucleotides (amino acids) of coat protein genes and 65.8% identity of nucleotides of 3' -UTR. Phylogenetic tree analysis of coat protein genes and 3 ' -terminal 1668nts of genome showed that they were closely related and clustered into same group, however, further studies are needed to conclude whether (hey are same virus specie. The another virus was ornilhogahim mosaic virus(OrMV), and it shared 98.5% (98.4%) identity of nucleotides (amino acids) of CP gene with an Australian isolate(AF203528).This is the first report of OrMV infection on narcissus crop. A fragment of 1852 nts was amplified in narcissus samples from Hangzhou by RT-PCR with the carlavirus-specific primers and sequenced. Its structure was identical to the 3' -terminal part of RNA genome of genus Carlavirm. Comparison of coat protein sequence showed that it had no more than 70% identities to PVM, PVS and LSV, hut was most closely related to the Chinese narcissus isolates (AJ311375 and AJ311376) with identities of 92.0% and 87.3% at amino acids level respectively. Phylogenetic tree analysis of CP gene also indicated that they seemed to he the same virus, tentatively named (Narcissus common latent virus, NCLV).The 3' -terminal RNAs of bean common mosaic virus (BCMV, 1663 nts and 1739 nts) were amplified from...
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