It is not possible to assign formatting to an entire row with a single property. However, you can select all the text boxes that make up the row and then use the Property pane to edit the BackgroundColor property of all of them at once. You would choose the "Expression" option and then enter an expression such as the following:
= If(Parameters!SilksColours.Value = Fields!SilksColours.Value, "Yellow", "White")
That code assumes the name of the dataset field is the same as the name of the parameter. If not, adjust as appropriate.