A Mutant with Constitutive Sexual Organ Development in Marchantia polymorpha L.

Abstract

In lower land plants, genes controlling the transition from vegetative growth to sexual reproduction have not yet been identified. In the dioecious liverwort Marchantia polymorpha, the transition to sexual reproduction accompanied with the formation of sexual organs on the gametophytic thallus is initiated under long-day conditions. By particle bombardment-mediated mutagenesis, we generated 2,100 tagged lines of mutant and identified a mutant of M. polymorpha which constitutively forms sexual organs. This mutant is fully fertile, showing that the mutation does not affect formation of male or female sexual organs per se. Genetic analysis reveals that this phenotype is caused by mutation of a single autosomal locus, suggesting that this mutation defines or controls a gene regulating the transition to sexual reproduction in M. polymorpha. (Sex Plant Reprod, in press)