The Key Laboratory of Plant Pathology of Hubei Province and The State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China.
U. S. Department of Agriculture, Agricultural Research Service, Washington State University, Pullman, WA 99164, USA.
Viruses. 2019 Jan 3;11(1):24. doi: 10.3390/v11010024.
A pink isolate (QT5-19) of was compared with three gray isolates of for growth and morphogenesis on potato dextrose agar (PDA), and for pathogenicity on tobacco. A double-stranded (ds) RNA mycovirus infecting QT5-19 was identified based on its genome feature and morphology of the virus particles. The results showed that QT5-19 grew rapidly and established flourishing colonies as the gray isolates did. However, it is different from the gray isolates, as it failed to produce conidia and sclerotia asthe gray isolates did. QT5-19 hardly infected tobacco, whereas the gray isolates aggressively infected tobacco. Two dsRNAs were detected in QT5-19, dsRNA 1 and dsRNA 2, were deduced to encode two polypepetides with homology to viral RNA-dependent RNA polymerase (RdRp) and coat protein (CP), respectively. Phylogenetic analysis of the amino acid sequences of RdRp and CP indicated that the two dsRNAs represent the genome of a novel partitivirus in the genus , designated here as Botrytis cinerea partitivirus 2 (BcPV2). BcPV2 in QT5-19 was successfully transmitted to the three gray isolates through hyphal contact. The resulting BcPV2-infected derivatives showed rapid growth on PDA with defects in conidiogenesis and sclerogenesis, and hypovirulence on tobacco. This study suggests that BcPV2 is closely associated with hypovirulence of .
一个粉红色的 isolate（QT5-19）与三个灰色的 isolate 相比，在土豆葡萄糖琼脂（PDA）上的生长和形态发生，以及对烟草的致病性。根据其基因组特征和病毒粒子的形态，鉴定出一种感染 QT5-19 的双链（ds）RNA 真菌病毒。结果表明，QT5-19 生长迅速，与灰色 isolate 一样建立了繁茂的菌落。然而，它与灰色 isolate 不同，因为它不能产生分生孢子和菌核，而灰色 isolate 可以。QT5-19 几乎不能感染烟草，而灰色 isolate 则强烈感染烟草。在 QT5-19 中检测到两条 dsRNA，dsRNA1 和 dsRNA2，分别推断编码两条与病毒 RNA 依赖性 RNA 聚合酶（RdRp）和外壳蛋白（CP）同源的多肽。RdRp 和 CP 氨基酸序列的系统发育分析表明，这两条 dsRNA 代表了一种新的 Botrytis cinerea 分病毒属（BcPV2）的基因组。通过菌丝接触，BcPV2 在 QT5-19 中成功地传递给了三个灰色的 isolate。由此产生的 BcPV2 感染的衍生物在 PDA 上生长迅速，分生孢子形成和菌核形成缺陷，对烟草的毒力降低。本研究表明，BcPV2 与的弱毒密切相关。
