Seed transmission of soybean vein necrosis virus: the first Tospovirus implicated in seed transmission

Soybean vein necrosis virus (SVNV; genus Tospovirus; Family Bunyaviridae) is a negative-sense single-stranded RNA virus that has been detected across the United States and in Ontario, Canada. In 2013, a seed lot of a commercial soybean variety (Glycine max) with a high percentage of discolored, deformed and undersized seed was obtained. A random sample of this seed was planted in a growth room under standard conditions. Germination was greater than 90% and the resulting seedlings looked normal. Four composite samples of six plants each were tested by reverse transcription polymerase chain reaction (RT-PCR) using published primers complimentary to the S genomic segment of SVNV. Two composite leaflet samples retrieved from seedlings yielded amplicons with a size and sequence predictive of SVNV. Additional testing of twelve arbitrarily selected individual plants resulted in the identification of two SVNV positive plants. Experiments were repeated by growing seedlings from the same seed lot...大豆叶脉坏死病毒（Soybean vein necrosis virus, SVNV；隶属于番茄斑萎病毒属（Tospovirus）、布尼亚病毒科（Bunyaviridae））为一种负链单链RNA病毒，目前已在美国全境及加拿大安大略省被检出。2013年，研究人员获取了一批商业化大豆品种（Glycine max）的种子批，该批种子中高比例存在变色、畸形及籽粒偏小的劣变种子。研究人员随机抽取该种子批中的部分种子，于标准培养环境下的生长室中进行播种，最终种子发芽率超过90%，培育得到的幼苗外观表现正常。研究人员选取4组复合样本开展检测，每组样本包含6株幼苗，采用已发表的、与SVNV S基因组片段互补的引物，通过逆转录聚合酶链式反应（reverse transcription polymerase chain reaction, RT-PCR）进行扩增。从幼苗中采集的2组复合叶样本扩增得到了与SVNV预期分子量大小和序列特征一致的扩增产物。后续对随机选取的12株单株幼苗进行补充检测，共鉴定出2株SVNV阳性植株。研究人员使用同一批种子培育幼苗，重复了上述实验……