Spray-induced gene silencing (SIGS) has potential to suppress pathogens in crops and is being developed as new crop protection tool. We are investigating the efficacy and mechanisms of exogenously applied double-stranded RNA (dsRNA) targeting virulence-related pathogen genes of the fungal pathogen Botrytis cinerea in grapevine. Successful adoption of SIGS in grapevine depends on elucidating the mechanisms by which dsRNA enters and moves within grapevine tissues, to ensure protection of the developing inflorescences and grape bunches where B. cinerea colonises. We present results pertaining to the uptake and persistence of dsRNA molecules in leaves and inflorescences of potted grapevine (Vitis vinifera) propagated in the glasshouse, as well as the systemic movement of dsRNAs within these potted grapevines, including to the inflorescence and developing berry. To achieve this, we have developed a new, validated methodology for relative and absolute quantification of applied dsRNA in planta utilising qRT-PCR. As part of a broader effort within the ARC Hub for Sustainable Crop Protection, the next stage of this work is to evaluate the efficacy and in planta movement of dsRNAs formulated as BioClay™ to aid persistence when applied under field conditions.