毒株、苗龄及温度对烟草苗期接种TMV试验的影响

病毒株系、苗龄、接种后培养条件是影响烟草病毒病发生发展的关键因素,为确保烟草接种TMV抗性鉴定和药效生测试验的准确性,在NV基因烟草和普通烟草上接种TMV,采用病毒生物学、qRT-PCR和Western blot技术,研究病毒的分离纯化、株系、稀释限点、传导路径、病害症状,以及N基因抗TMV的温敏性.结果显示,TMV为...

Effects of virus strain,seedling age and temperature in TMV inoculation of tobacco at seedling stage

Viral strain, seedling age and culture conditions are the key factors to influence post-inoculation induction of disease symptoms. To ensure the accuracy of tobacco’s resistance evaluation and efficacy of antiviral agents against TMV, the TMV inoculation was done on N gene and common tobacco. Assays like virus biology, qRT-PCR and Western blot, were performed to research TMV separation and purification, virus strain identification, dilution limit concentration, transmission route, symptoms development, and thermosensitivity of N gene. The results showed that TMV was U1 strain, preserved on K326 for 50-65 days still had a strong pathogenicity, with dilution limit concentration of 10⁵. The concentration of the inoculum should be diluted by 100 times. After inoculation, TMV systemically spread from the inoculated leaf to the main stem, down to the root, up to the topmost leaf, then to the upper leaf, and finally to the lower leaf. The whole plant was covered with virus in 12-16 days, leaf mosaic and deformity was significant in 21-28 days. The systematic investigation time should be within 2-3 weeks. Temperature and seedling age affected the resistance response of N gene tobacco to TMV. The culture temperature after inoculation should be maintained at 25℃-27℃, and the seedling age should be 6-7 leaves.