The ornamental hemp palm Trachycarpus fortunei has an unstable sexual expression system with genetic markers suggesting evolution toward an XY sex determination system.
Plant geneticists, invasion biologists, and palm reproductive biology researchers.
15%+ offspring from male-femalepalms that produce fertile female flowers despite appearing male, enabling high dispersal
What the researchers found
Sexual differentiation appears late in floral development, with genetic analysis revealing linked heterozygous regions in males suggesting at least 15% of wild palms are offspring of males that can also produce fertile female flowers.
Why it matters
Understanding the reproductive biology of this invasive ornamental palm helps explain its high dispersal ability on the southern side of the Alps.
The numbers in context
31,000 SNPs analyzed across 122 palms from 21 wild populations. At least 15% of wild palms are direct offspring of males producing fertile pistillate flowers.
How the study worked
SEM and anatomical study of floral development combined with genome-wide association study (31,000 SNPs, 122 palms, 21 populations) for sex determinism.
Who was studied
122 Trachycarpus fortunei palms from 21 wild populations in the southern Alps.
What this study cannot tell us
Limited to southern Alps populations. Complex sexual expression makes definitive genetic sex determination difficult. SNP density may miss fine-scale genetic variation.
How to read the evidence
Robust molecular study combining genomics and developmental morphology; strong botanical evidence.
When this study was published
Recent genomic study of invasive palm populations.
The bigger picture
This study of the hemp palm (not related to cannabis) contributes to understanding how dioecious plants can evolve flexible sexual expression, with ecological implications for invasive species management.
Replication
Focused on southern Alps populations; broader geographic sampling would add context.
Funding
Not specified in abstract
Conflicts of interest
Not specified in abstract
Questions still open
- Could the flexible sexual system be targeted for invasive species management?
- Is this evolutionary path toward XY determination common in palms?
Read the original research
Not just females and males: Unravelling the complex sex determinism of the hemp palm, Trachycarpus fortunei.
American journal of botany, 110(12), e16257
Citation
Jousson, Antoine; Naciri, Yamama; Christe, Camille; Marazzi, Brigitte; Stauffer, Fred. (2023). Not just females and males: Unravelling the complex sex determinism of the hemp palm, Trachycarpus fortunei.. American journal of botany, 110(12), e16257. https://doi.org/10.1002/ajb2.16257