An artificial inoculation method for evaluating rice resistance to RBSDV.

Rice black-streaked dwarf virus (RBSDV) disease, caused by rice black-streaked dwarf virus and transmitted by the small brown planthopper (Laodelphax striatellus Fallén, SBPH), is a devastating viral disease severely impacting global rice production. The cultivation and promotion of resistant varieties is considered the most economical and effective control strategy. However, effectiveness of field-based resistance identification is hindered by environmental variability, seasonal limitations of SBPH outbreaks, and inconsistent virus pressure, leading to unreliable results. Therefore, we developed an efficient and reliable artificial inoculation system for RBSDV-resistant rice materials screening under controllable laboratory conditions. This system encompasses optimized procedures for material preparation, inoculation methodology, disease phenotyping and resistance evaluation. We directly inoculated 1st-2nd instar SBPH nymphs onto the RBSDV infected plants and obtained nymphs with high viruliferous rates. Then, to generate a stable laboratory virus source, these viruliferous nymphs were used to inoculate highly susceptible rice seedlings (e.g., Suyunuo). Subsequent inoculation cycles using these viruliferous rice seedlings consistently produced SBPH populations with high viruliferous rates (average about 42.4%). This system enables continuous, year-round resistance evaluation, breaking through the limitation of environmental dependence in field identification. This method will significantly accelerate the breeding of RBSDV disease resistant rice varieties. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-025-01612-x.