Transcription factor. Involved in apical dominance. Represses the growth of axillary organs (e.g. lateral branches), but enables the formation of female inflorescences. Regulates the number and length of axillary branches. Expressed in axillary inflorescence primordia, immature internodes below these primordia, and immature husk surrounding these primordia. TB1 is a major QTL of the evolution from the teosinte to the maize morphology.