Efficient virus-induced gene silencing in Primulina using two virus vector systems

•First establishment of a VIGS system in the ornamental plant genus Primulina.•Pronounced photobleaching phenotype observed in VIGS-treated Primulina plants.•Optimization of TRV-based VIGS system with a stable silencing efficiency of 75 % under specific conditions.•Validation of TRV and Calcuv-based VIGS systems as breakthrough tools for gene function analysis in Primulina genus. Virus-induced gene silencing (VIGS) is a post-transcriptional gene silencing method and an effective technique for analyzing plant gene function. However, to date there have been no reports on the establishment of a VIGS system in Primulina, which includes over 200 species of plants, most of which have high ornamental value. In this study, we successfully established a VIGS system in P. 'Alfonso' and P. carinata using TRV vector system with phytoene desaturase (PDS) as marker gene. After being treated with pTRV2-PDS vector, both P. 'Alfonso' and P. carinata plants showed a pronounced photobleaching phenotype. The system was further optimized by exploring different infection conditions. The optimized TRV-based VIGS system was as follows: Agrobacterium OD600 = 0.5, leaf vacuum infiltration, and the silencing efficiency of the system can reach 75 %. Chlorata42 was used as another marker gene and further verified the establishment of TRV VIGS system in P. 'Alfonso'. In addition, the CaLCuV-based VIGS system was also established with PDS as marker gene in P. 'Alfonso'. The establishment of the TRV-based and CaLCuV-based VIGS systems provided a breakthrough in the validation methods for identifying gene function in Primulina genus.