Abstract: 【Objective】Virus-induced gene silencing (VIGS) technology has been widely applied in the field of functional gene research in plants. Tobacco rattle virus-mediated gene silencing technology was used in the interaction between soybean and soybean mosaic virus (SMV) for gene function evaluation, and a TRV-mediated gene transient silence system in soybean was established.【Method】Soybean cv. Jidou 7 (J7) was used as material, and specifically amplified part of the GmPDS gene fragment from J7 leaves, and then was inserted into the plasmid pTRV: RNA2; The Agrobacterium carried with TRV or TRV:GmPDS were injected into the first true leaves of J7. After that, the upper non-inoculated leaves were observed and GmPDS gene’s expression level was confirmed by semi-quantitative RT-PCR analysis. In order to investigate the effect of inoculation with TRV on the resistance of soybean to SMV infection, the first true leaves of soybean inoculated with TRV for 10 days , then were inoculated with SMV strain N3 or SC-8. The control treatments were conducted by inoculating N3 or SC-8 alone. At 5 days after inoculating SMV, the phenotypes of upper uninoculated leaves were observed and SMV coat protein CP was detected. 【Result】At 25 days after injected with Agrobacterium suspension carrying TRV: GmPDS intothe first true leaves, the upper uninoculated leaves showed whitening phenotype and expression level of GmPDS was decreased significantly by semi-quantitative RT-PCR analysis. Based on this, soybean leaves injected with Agrobacterium suspension (carrying TRV) were then inoculated with SMV. J7 and SMV strains N3 and SC-8 were used to constitute incompatible and compatible combinations. Inoculated with TRV and then with SMV strains N3 or SC-8, the phenotype of upper uninoculated leaves were consistent with the upper leaves after inoculated with SMV alone. Leaves were taken for viral coat protein CP test. It was found that when inoculated with N3 alone, or pre-inoculated with TRV and then inoculated with N3, the coat protein CP was not detected on the upper leaves. If inoculated with SC-8 alone, or pre-inoculated with TRV and then inoculated with SC-8, the viral coat protein CP was detected on the uninoculated upper leaves. These results showed that the TRV had no influence on the performance of soybean resistance to SMV. The similar results were got on susceptible cv. Nannong 1138-2. 【Conclusion】The TRV-VIGS system in soybean was established in this experiment. The TRV has no influence on the performance of soybean resistance to SMV.

Key words: virus-induced gene silencing (VIGS), soybean; tobacco rattle virus; soybean mosaic virus, soybean phytoene desaturase (GmPDS)