The present invention concerns a method for increasing plant yield by increasing activity in a plant of an Os-MADS18-like polypeptide or a homologue thereof. One such method comprises introducing into a plant an OsMADS18-like nucleic acid or variant thereof. The invention also relates to transgenic plants having introduced therein an OsMADS18-like nucleic acid or variant thereof, which plants have increased yield relative to corresponding wild type plants. The present invention also concerns constructs useful in the methods of the invention.