Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA.
Department of Plant Protection Biology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
Viruses. 2021 Apr 12;13(4):662. doi: 10.3390/v13040662.
Thrips-transmitted tomato spotted wilt orthotospovirus (TSWV) continues to be a constraint to peanut, pepper, tobacco, and tomato production in Georgia and elsewhere. TSWV is being managed by an integrated disease management strategy that includes a combination of cultural practices, vector management, and growing virus-resistant varieties where available. We used a non-transgenic strategy to induce RNA interference (RNAi)-mediated resistance in tobacco () plants against TSWV. Double-stranded RNA (dsRNA) molecules for the NSs (silencing suppressor) and N (nucleoprotein) genes were produced by a two-step PCR approach followed by in vitro transcription. When topically applied to tobacco leaves, both molecules elicited a resistance response. Host response to the treatments was measured by determining the time to symptom expression, and the level of resistance by absolute quantification of the virus. We also show the systemic movement of dsRNA_N from the inoculated leaves to younger, non-inoculated leaves. Post-application, viral siRNAs were detected for up to nine days in inoculated leaves and up to six days in non-inoculated leaves. The topical application of dsRNAs to induce RNAi represents an environmentally safe and efficient way to manage TSWV in tobacco crops and could be applicable to other TSWV-susceptible crops.
烟粉虱传播的番茄斑萎病毒（TSWV）仍然是佐治亚州和其他地区花生、胡椒、烟草和番茄生产的一个制约因素。TSWV 通过综合疾病管理策略进行管理，该策略包括结合文化实践、媒介管理和种植可用的抗病毒品种。我们使用非转基因策略诱导烟草（）植物对 TSWV 产生 RNA 干扰（RNAi）介导的抗性。双链 RNA（dsRNA）分子用于 NSs（沉默抑制子）和 N（核蛋白）基因是通过两步 PCR 方法产生的，然后进行体外转录。当局部应用于烟草叶片时，两种分子都引起了抗性反应。通过确定症状表达的时间来衡量宿主对处理的反应，通过绝对定量病毒来衡量抗性水平。我们还显示了 dsRNA_N 从接种叶片到较年轻的未接种叶片的系统运动。接种后，在接种叶片中检测到病毒 siRNA 长达九天，在未接种叶片中检测到长达六天。dsRNA 的局部应用诱导 RNAi 是一种在烟草作物中管理 TSWV 的安全有效的方法，也可应用于其他易受 TSWV 影响的作物。
