Abstract: Virus-induced gene silencing (VIGS) is a widely applied natural mechanism for plant defense against virus, which can effectively prevent potato virus Y disease. Taking the control effect of VIGS expression vector fermentation broth on potato virus Y disease as detection index, this study screened the culture medium needed by fermenting the best fermentation broth, fermentation conditions and application methods. The results showed that the optimal medium was YEP (yeast extract broth peptone), optimal fermentation conditions were medium volume 60 mL/200 mL, initial pH 7.0, fermentation temperature 30℃ and shaking culture time 24 h. The optimal application methods were dilution 100 times, “leaf spraying + transplanting root irrigation”, and “mixture of VIGS biologics containing PVY CP and HC-Pro gene fragments”. The above results provided a theoretical basis for fermenting VIGS biocontrol agent, and layed a foundation for the field application.

Key words: potato virus Y, virus-induced gene silence, optimization of fermentation condition, application method

摘要： 病毒诱导的基因沉默（virus-induced gene silence，VIGS）是植物病毒病防治方法之一，能够有效防治马铃薯Y病毒病。以VIGS表达载体发酵液对烟草马铃薯Y病毒病的防治效果为检测指标，筛选最佳发酵液发酵所需的培养基、发酵条件和施用方法。结果表明：VIGS表达载体发酵液最优培养基是YEP培养基；最优发酵条件为装瓶量60 mL/200 mL、初始pH 7.0、培养温度30℃、振荡培养24 h；施用方法以 “原液稀释100倍”、“剪叶后喷施+移栽时灌根”和“含PVY CP和HC-Pro基因片段的VIGS载体发酵液混合使用”的施用效果最佳。上述结果为抗马铃薯Y病毒病的VIGS生防剂发酵提供了理论依据，也为其田间应用打下基础。

关键词: 马铃薯Y病毒, 病毒诱导的基因沉默, 发酵条件优化, 施用方法