Bajet N B, Unruh T R, Druffel K L, Eastwell K C
United States Department of Agriculture-Agricultural Research Service, Yakima Agricultural Research Laboratory, Wapato, WA 98951.
Washington State University, Department of Plant Pathology, Pullman 99164.
Plant Dis. 2008 Feb;92(2):234-238. doi: 10.1094/PDIS-92-2-0234.
Little cherry disease, one of the major viral diseases of sweet cherry (Prunus avium) worldwide, is associated with either of two closteroviruses, Little cherry virus 1 (LChV-1) and Little cherry virus 2 (LChV-2). Two sets of primers corresponding to a portion of the replicase gene of LChV-1 and LChV-2 were used in one-tube reverse-transcription polymerase chain reactions to detect these viruses in total RNA extracts of field-collected sweet cherry tissues. LChV-1 and LChV-2 were detected both alone and in combination in five sweet cherry orchards in Washington State. Sequence analysis of a 240-nucleotide (nt) fragment of the replicase open reading frame (ORF)1b and a 232-nt fragment from a portion of ORF8 and the 3' untranslated region (UTR) of LChV-1 indicated that North American (NA) isolates shared 90 to 99% nucleotide identity in both genome segments analyzed. In contrast, comparisons of NA isolates to two Eurasian isolates of LChV-1 indicated shared nucleotide identities of 79 to 82% in the replicase fragment and 89 to 90% in the ORF8/3'UTR fragment. Sequence variation in the replicase region did not affect detection of LChV-1 in 12 isolates using the replicase-specific primers reported here. This article represents the first report of LChV-1 and LChV-2 in sweet cherry in Washington.
小樱桃病是全球甜樱桃（Prunus avium）的主要病毒病之一，与两种长线形病毒中的任何一种有关，即小樱桃病毒1（LChV-1）和小樱桃病毒2（LChV-2）。在一管逆转录聚合酶链反应中，使用了两组分别对应于LChV-1和LChV-2复制酶基因一部分的引物，以检测田间采集的甜樱桃组织总RNA提取物中的这些病毒。在华盛顿州的五个甜樱桃果园中，单独或同时检测到了LChV-1和LChV-2。对LChV-1复制酶开放阅读框（ORF）1b的240个核苷酸（nt）片段以及ORF8一部分和3'非翻译区（UTR）的232 nt片段进行序列分析表明，北美（NA）分离株在分析的两个基因组片段中核苷酸同一性为90%至99%。相比之下，将北美分离株与LChV-1的两个欧亚分离株进行比较，结果显示在复制酶片段中核苷酸同一性为79%至82%，在ORF8/ 3'UTR片段中为89%至90%。使用本文报道的复制酶特异性引物，复制酶区域的序列变异并不影响对12个分离株中LChV-1的检测。本文是华盛顿甜樱桃中LChV-1和LChV-2的首次报道。
