Floating Water Weed Could Be Used as Biofuels Feedstock

The Science

Duckweed is one of the world’s smallest and fastest-growing flowering plants and can be a hard-to-control weed in ponds and small lakes. It shows great promise as a biofuel feedstock, however, and private companies are already exploring its use in fuel production. Researchers at Rutgers University, the Department of Energy’s Joint Genome Institute, and several other facilities recently sequenced the complete genome of Greater Duckweed (Spirodela polyrhiza) and analyzed it in comparison with several other plants, including rice and tomato. S. polyrhiza’s very small genome is missing many genes for plant maturation and production of cellulose and lignin but has more genes than comparable plants for starch production. Determining which genes produce desirable traits will allow researchers to create new varieties of duckweed with enhanced biofuel traits.


Spirodela has a genome with no signs of recent retrotranspositions but signatures of two ancient whole-genome duplications, possibly 95 million years ago (mya), older than those in Arabidopsis and rice. Its genome has only 19,623 predicted protein-coding genes, which is 28% less than the dicotyledonous Arabidopsis thaliana and 50% less than monocotyledonous rice. Researchers propose that at least in part, the neotenous reduction of these aquatic plants is based on readjusted copy numbers of promoters and repressors of the juvenile-to-adult transition. The Spirodela genome, along with its unique biology and physiology, will stimulate new insights into environmental adaptation, ecology, evolution and plant development, and will be instrumental for future bioenergy applications.

BER Program Manager

Ramana Madupu

U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]


W. Wang, G. Haberer, H. Gundlach, C. Gläßer, T. Nussbaumer, M.C. Luo, A. Lomsadze, M. Borodovsky, R.A. Kerstetter, J. Shanklin, D.W. Byrant, T.C. Mockler, K.J. Appenroth, J. Grimwood, J. Jenkins, J. Chow, C. Choi, C. Adam, X.-H. Cao, J. Fuchs, I. Schubert, D. Rokhsar, J. Schmutz, T.P. Michael, K. F. X. Mayer and J. Messing. 2014. “The Spirodela polyrhiza Genome Reveals Insights into Its Neotenous Reduction Fast Growth and Aquatic Lifestyle,” Nature Communications 5, 3311. DOI:10.1038/ncomms4311.