Investigating the Role of INDETERMINATE1 in Controlling the Floral Transition in Teosinte (Zea mays ssp. parviglumis)

Abstract

In all higher plants, reproductive growth is initiated by mobile signalling proteins known as ‘florigens’. Maize (Zea mays ssp. mays) and its progenitor teosinte (Zea mays ssp. parviglumis), contain florigens encoded by members of the Zea CENTRORADIALIS (ZCN) gene family. Teosinte is a tropical plant that requires short day photoperiods to flower whereas modern temperate maize is an autonomous plant that flowers at the same time regardless of photoperiod. Autonomous flowering in maize is regulated by the indeterminate1 (id1) gene such that id1 mutants flower extremely late. To investigate how id1 controls flowering in relation to photoperiod, an id1 mutant allele was introgressed into teosinte. This study elucidates florigenic mechanisms in Zea mays by further exploring florigen function in temperate maize and teosinte, and how id1 regulates the autonomous and photoperiod floral induction pathways. Ultimately, ID1 regulates flowering in teosinte independent from the photoperiod pathway and carbohydrate metabolism.