% of protein in potato is . . . . . . . .

Potatoes are low in protein, ranging from 1 - 2% when fresh and 8 - 9% by dry weight.
The major protein found in protein is Patatin, also known as tuberin.
Potatoes (Solanum tuberosum) are characterized by a large starch content, which supplies energy and by the presence of many nutritionally beneficial components such as proteins, fibres, vitamins and organic acids.