Yes, the fuel selector typically must be selected to "Both" for takeoff and landing.
The Cessna 172 Type Certificate Data Sheet (TCDS) requires a placard for most early serial numbers (all models through S/N 17265684 except 17261445 and 17261578). This placard is to be located forward of the fuel selector valve and must state:
Both tanks on for takeoff and landing.
Note that this placard is required by certification for airworthiness, constitutes a limitation, and is to be followed by the pilot. See 14 CFR 91.9:
§91.9 Civil aircraft flight manual, marking, and placard requirements.
(a) Except as provided in paragraph (d) of this section, no person may operate a civil aircraft without complying with the operating limitations specified in the approved Airplane or Rotorcraft Flight Manual, markings, and placards, or as otherwise prescribed by the certificating authority of the country of registry.