黄瓜花叶病毒两个甜瓜分离物的基因组及其侵染性克隆

为明确黄瓜花叶病毒（cucumber mosaic virus,CMV）甜瓜分离物的分子变异情况及其侵染性，对2个甜瓜分离物CH99和XH18的基因组进行克隆、测序和分析，并通过构建全长cDNA克隆分析其侵染性。结果显示，黄瓜花叶病毒甜瓜CH99分离物3条RNA长度分别为3 356、3 049和2 211 nt，甜瓜XH18分离物3条RNA长度分别为3 381、3 048和2 217 nt。分离物CH99与XH18的核苷酸序列一致性为89.40%～95.80%，氨基酸序列一致性为90.00%～97.80%,CH99分离物与其他CMV分离物的核苷酸和氨基酸序列一致性平均值分别为79.23%～89.29%和73.52%～93.90%,XH18分离物与其他CMV分离物的核苷酸和氨基酸序列一致性平均值分别为79.81%～89.83%和74.02%～95.14%。遗传发育分析显示，这2个分离物均属于亚组IB成员。接种试验结果显示，分离物CH99和XH18的侵染性克隆构建成功，这2个分离物均能系统侵染本生烟、甜瓜和黄瓜，并在本生烟和甜瓜上引起较严重的症状，在黄瓜上引起的症状较弱，而二者均不能侵染西...

The genome analysis and infectious clone construction of two melon isolates of cucumber mosaic virus

To investigate the molecular variation and infectivity of cucumber mosaic virus(CMV) isolates from melon, the genome sequences of two melon isolates CH99 and XH18 were cloned, sequenced and analyzed, and their infectious cDNA clones were constructed and used to inoculate Nicotiana benthamiana, melon, watermelon and cucumber. The results showed that the three RNA lengths of isolate CH99 were 3356, 3049 and 2211 nt, while the three RNA lengths of isolate XH18 were 3381, 3048 and 2217 nt. The nucleotide sequence identity between CH99 and XH18 was 89.40%-95.80%, and their amino acid sequence identity was 90.00%-97.80%. The average nucleotide and amino acid sequence identity between CH99 and other isolates were 79.23%-89.29% and 73.52%-93.90%,respectively. The average nucleotide and amino acid sequence identity between XH18 and other isolates were 79.81%-89.83% and 74.02%-95.14%, respectively. Phylogenetic analysis showed that both isolates belonged to subgroup IB. The inoculation showed that the infectious clones were successfully constructed, and they both could systematically infect N. benthamiana, melon and cucumber, causing serious symptoms on N. benthamiana and melon, but weak symptoms on cucumber, whiel neither of them could infect watermelon.