In freshwater bodies all over the world float tiny green discs of duckweed — among the smallest flowering plants on Earth. Each of them measures only a few millimetres, yet inside it retains the basic body plan of a shoot characteristic of far larger herbaceous plants. How this is possible has been discovered by researchers at the University of Nottingham. Their work, published on 7 October 2026 in the journal Current Biology, shows that duckweed does not lose the details of its construction but compacts them and fuses them into a single whole.
The closest relatives of duckweeds — members of the arum family — include some of the largest herbaceous plants in the world. For a long time the miniature size of duckweeds was taken as a sign of primitiveness or simplification. However, microscopy and gene expression analysis showed the opposite: the main structures of the shoot have not disappeared, they are simply tightly packed and partly fused. The leaf-like and stem-like zones in the body of duckweed turned out to be a hybrid organ in which stem and leaf are merged into one.
The lead author of the work, Dr Anthony Bishopp, explains the essence of the finding thus: plants took the path of compression rather than abandonment of details. In animals, reduction in size often goes hand in hand with the loss of organs: in miniature frogs the lungs are reduced, and in tardigrades body segments are lost. In duckweeds, however, the "blueprint" is preserved in full, only in a highly compacted form. According to Bishopp, what surprised the team was that, on close study, the basic organisation of the shoot turned out to be in place. Such a path opens a new view of how plants evolve towards small sizes.
An important caveat: the study concerns rooted duckweeds. In even smaller relatives, for example in Wolffia, roots and tissues conducting water and nutrients have been lost, and the authors state directly that these species were not studied directly in the work.
Besides fundamental science, duckweed attracts attention as a possible source of food and protein. It is being considered for agriculture on Earth and even as a product for long space missions. One of its merits is speed: the fronds double in about one to three days, which makes it possible to obtain a harvest in very short cycles. At the same time, duckweed has not yet become a full-fledged crop, unlike the familiar plants that selection has perfected over centuries. That is precisely why understanding its structure is so important: without it, it is hard to predict how it grows, develops and how it can be improved.
A co-author of the study, Dr Alex Ware, emphasises: the temptation to consider duckweeds either primitive or as having lost part of their organs is mistaken. The new data add to the growing body of knowledge about the plant and will help turn duckweed into a future agricultural crop. This is especially important in the context of the search for sustainable and fast-growing sources of food.
The discovery shows that nature solves the problem of reduction not through simplification but through the rearrangement of already existing elements. For humans this means new opportunities: by understanding the mechanisms of duckweed growth, scientists will be able to come closer to creating compact and nutritious plants for the future.
By studying how duckweed fits into a tiny space without losing its essence, we gain a key to a more careful and inventive use of the plant world.
