Scientists have made a breakthrough in understanding how flowering plants like ginger control the movement of their reproductive organs, which is crucial for successful pollination and genetic diversity. A new paper published in Nature Plants, co-authored by Professor Spencer Barrett, breaks down the genetics behind the ginger plant Alpinia mutica.

In many flowering plants, the anthers (male parts) and styles (female parts) mature at different times, a mechanism known as dichogamy, which helps to mitigate self-pollination and promote cross-breeding. This study focused on Alpinia mutica, a ginger species that naturally synchronizes the movements of anthers and styles throughout the day. This species exhibits both dichogamous flowering behaviors, protandry (where the male parts mature first) and protogyny (where the female parts mature first), withing a single population. This creates a natural system for studying how these reproductive organ movements are controlled.

The researchers discovered that a single gene, called SMPED1, is critical in controlling when the anthers dehisce (release pollen) and when the styles move, the order of which determines whether a flower is protandrous or protogynous. By sequencing and analyzing the ginger genome in detail, the team identified the SMPED1 gene and confirmed its function across other plant species. They found that a specific genetic deletion near the SMPED1 gene influences its activity, effectively switching the reproductive timing. This gene is conserved in angiosperms, meaning it likely works similarly in other flowering plants. 

John Stinchcombe, Distinguished Professor of Ecological Genetics commented on the findings “This is really beautiful work showing the promise of combining genetics and population genomics. Their findings add to the small-but-growing list of studies where plant sexual polymorphisms are due to genetic deletions. An open question is how much Mendelian traits, in general, are due to insertions and deletions, rather than nucleotide polymorphisms.” 

This discovery provides new insights into the mechanisms governing plant reproduction and evolution and since the timing of sexual function is important in plant breeding could be exploited for crop improvement.