It shall be unlawful to use or employ the term “certified” or the term “inspected,” or any term or terms conveying a meaning substantially equivalent to the meaning of either of these terms, either orally or in writing, printing, marking, or otherwise in reference to or in connection with, or in advertising or characterizing or labeling seed potatoes or the containers thereof, unless such potatoes shall have been duly inspected and certified pursuant to the provisions of sections 21.111 to 21.122.