Lewandowski Dennis J, Hayes Amanda J, Adkins Scott
Department of Plant Pathology, The Ohio State University, Columbus 43210.
United States Department of Agriculture, Agricultural Research Service, Fort Pierce, FL 34945.
Plant Dis. 2010 May;94(5):542-550. doi: 10.1094/PDIS-94-5-0542.
Over 100 years after its discovery, Tobacco mosaic virus (TMV) remains an economically important pathogen for producers of many vegetatively propagated crops including petunias (Petunia × hybrida). To directly address this concern, we have developed a robust system to determine efficacy of disinfectants for treating TMV-contaminated cutting tools using a combination of preliminary screens and replicated trials. Contrary to widely held beliefs, wild-type (wt) TMV and four additional tobamovirus species infected four petunia cultivars without producing obvious viral symptoms. In contrast, a petunia isolate of TMV with 99.0% (nucleotide) and 99.4% (amino acid) coat protein sequence identity to wt TMV produced symptoms on all but one tested cultivar. We also show that TMV transmission can occur up to the twentieth petunia plant cut following a single cutting event on a TMV-infected plant. Although many new products are now available, treatment of TMV-contaminated tools with a 20% (wt/vol) solution of nonfat dry milk (NFDM) plus 0.1% Tween 20 or a 1:10 dilution of household bleach (0.6% sodium hypochlorite), two "old standbys", completely eliminated TMV transmission to petunias. Treatment of contaminated tools with 1% (wt/vol) Virkon S or 20% NFDM also significantly reduced the incidence of infected petunias. Other treatments identified in the preliminary screens are candidates for the second phase of screening that simulates contamination during the process of taking cuttings.
烟草花叶病毒（TMV）被发现100多年后，对于包括矮牵牛（Petunia × hybrida）在内的许多无性繁殖作物的生产者来说，它仍然是一种具有重要经济影响的病原体。为了直接解决这一问题，我们开发了一个强大的系统，通过初步筛选和重复试验相结合的方式，来确定消毒剂处理受TMV污染的切割工具的效果。与广泛持有的观点相反，野生型（wt）TMV和另外四种烟草花叶病毒感染了四个矮牵牛品种，但未产生明显的病毒症状。相比之下，一种与wt TMV外壳蛋白序列同一性为99.0%（核苷酸）和99.4%（氨基酸）的矮牵牛TMV分离株，在除一个测试品种外的所有品种上都产生了症状。我们还表明，在受TMV感染的植株上进行一次切割操作后，TMV可传播到多达第20株被切割的矮牵牛植株上。尽管现在有许多新产品可供使用，但用20%（重量/体积）脱脂奶粉（NFDM）加0.1%吐温20的溶液或家用漂白剂（0.6%次氯酸钠）1:10稀释液这两种“老牌产品”处理受TMV污染的工具，能完全消除TMV向矮牵牛的传播。用1%（重量/体积）的卫康S或20%的NFDM处理受污染的工具，也能显著降低感染矮牵牛的发生率。在初步筛选中确定的其他处理方法，是模拟扦插过程中污染情况的第二阶段筛选的候选方法。
