Which plant can grow faster plant sunlight without water or plant water without sunlight?
However, assuming two plants have been growing with water AND sunlight and you stop watering one and place the other in the dark, both plants will continue to grow for a time, one with the water it contains and the other with the food it has already made. The one in the dark will however make more growth before it dies than the one kept in the light because sunlight destroys an enzyme that causes the growing tip to elongate.