Compositions and methods for modulating flower organ development, leaf formation, phototropism, apical dominance, fruit development, initiation of roots, and for increasing yield in a plant are provided. The compositions include a ZMM28 sequence. Compositions of the invention comprise amino acid sequences and nucleotide sequences selected from SEQ ID NOS: 1-2 as well as variants and fragments thereof. Nucleotide sequences encoding the ZMM28 sequences are provided in DNA constructs for expression in a plant of interest are provided for modulating the level of a ZMM28 sequence in a plant or a plant part are provided. The methods comprise introducing into a plant or plant part a heterologous polynucleotide comprising a ZMM28 sequence of the invention. The level of the ZMM28 polypeptide can be increased or decreased. Such method can be used to increase the yield in plants in one embodiment, the method is used to increase grain yield in cereals.
