Directional water transport system resolves fertilization-dispersal conflicts in Marchantia.

A directional water transport system on the female archegoniophore of Marchantia polymorpha enables efficient sperm delivery to elevated archegonia, supporting water-mediated fertilization on water-depriving land.

• Why it matters: Fertilization and dispersal impose conflicting functional demands on land plants, yet how integrated traits are assembled to resolve these conflicts is unclear.
• What they did: The study maps coordinated surface structures on the archegoniophore and shows their development is controlled by MpLAS, a GRAS transcription factor, via regulation of cell-growth-coupled cell division.
• The result: It finds MpGRAS10 regulates gibberellin-related biosynthesis for stalk formation, and evolutionary reconstruction suggests a stepwise assembly where fertilization-enhancing traits emerge after dispersal-facilitating stalk emergence.

AI summary of the abstract · may contain errors · not medical advice · read the paper.