Duckweeds are the smallest and fastest-growing flowering plants. They are free-floating aquatic monocots in the family Lemnaceae (order Alismatales), comprising around 36 species across five genera — Spirodela, Landoltia, Lemna, Wolffiella and Wolffia. Their body plan is highly reduced: a small flat or globular frond a few millimetres (or less) across, with few or no roots, reproducing mostly by clonal budding.
Why duckweed?
That combination of traits makes duckweed unusually useful, both as a research organism and as a crop:
- Fast, clonal growth. Some species can double their biomass in a couple of days, so experiments run quickly and populations stay genetically uniform.
- Whole-plant simplicity. With minimal tissue differentiation, the whole plant can be handled almost like a suspension culture — convenient for imaging, screening and physiology.
- Small genomes. Genome size varies roughly 14-fold across the family, from about 150 Mb in Spirodela polyrhiza upward, and high-quality reference genomes now exist for several species.
- Applied potential. High protein content, efficient nutrient uptake and rapid growth underpin interest in duckweed for human food and animal feed, wastewater treatment and phytoremediation, starch and bioenergy, molecular farming, and as a candidate crop for controlled-environment and space agriculture.
Duckweed in Australia
The ACDC curates Australian Lemnaceae for research. Among them is Wolffia australiana, which has the smallest genome in its genus and is native to Australia and New Zealand. A barcoded, well-documented collection of local strains supports research on native diversity and gives researchers here reliable, biosecurity-cleared material to work with. See the database for what's currently held.
Selected reading
A good entry point to the modern field is the community review by Acosta et al., "Return of the Lemnaceae: duckweed as a model plant system in the genomics and postgenomics era" (The Plant Cell, 2021, vol. 33, pp. 3207–3234). For genome assemblies and annotation tools, see lemna.org. Recent work from other groups includes:
- Stepanenko et al. (2025) Genome diversity and evolution of the duckweed section Alatae. The Plant Journal.
- Sree et al. (2025) 7th International Conference on Duckweed Research and Applications — a concise snapshot of where the field is now. Plants.
- An et al. (2018) Genomes and transcriptomes of duckweeds. Frontiers in Chemistry.
The quarterly Duckweed Forum newsletter also rounds up newly published duckweed papers in every issue — the easiest way to keep up. More on the external links page.