植物进化生态研究组知识库

In many flowering plants, male and female reproductive organs mature at different times to avoid self-pollination, a phenomenon termed dichogamy. Most dichogamous species are either protandrous or protogynous, making this strategy difficult to study genetically. However, in the ginger Alpinia mutica, protandrous and protogynous floral morphs co-occur within populations, and the synchronized rhythmic movement of styles and dehiscence of stamens promotes cross-pollination between morphs. Here we demonstrate that a single Mendelian locus with a dominant allele governing protogyny controls sexual polymorphism. We used haplotype-resolved genomes and population genomics to identify the dichogamy-determining region, revealing a large deletion in the protandrous morphotype. We found that the key gene SMPED1, located adjacent to the deletion, governs the timing of anther dehiscence and style movement. SMPED1 is widespread among angiosperms and probably has conserved function. Our findings represent a new genetic characterization of a key mating system gene controlling the synchrony of sex organs in flowering plants.