Hormonal ‘Code’ for the Number of Maize Tassel Branches

Maize is a main cereal crop in China. The number of tassel branches significantly affects density-tolerant plant architecture, which is the key to increasing yield. Currently, multiple genes associated with tassel branch number, many of which are closely related to plant hormone pathways, have been cloned and identified. This review summarizes the roles and signaling pathways of auxin, cytokinin, strigolactone, gibberellin and abscisic acid in regulating maize tassel branch number, preliminarily investigates the interaction mechanisms among hormones and the impact of environmental factors on hormonal regulatory mechanisms, and outlines the hormonal regulation network for tassel branch number in maize. These findings suggest that plant hormones integrate environmental factors to regulate the tassel branch number. This review aims to provide a theoretical reference for revealing the molecular mechanisms of phytohormone regulation of maize tassel branch number and to lay a scientific foundation for novel cultivars of the maize ideotype through plant hormones.