Receptor-like kinase protein that regulates the size of the floral meristem. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Expressed in shoot apical meristem, and after transition to the reproductive phase, detected in the inflorescence and the floral meristems. Expressed uniformly throughout the meristems. Expressed also in floral organ primordia, such as the palea, lemma, lodicules, stamens, carpels and ovules. Expressed in the floral meristem even after the initiation of carpel primordia. Semi-dwarf with altered numbers of floral organs and rachis branches. Reduced number of tillers. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family.