Fastest Crowing Plant in the World Observed.

• Position: BOTANY

Wolffia, also known as duckweed, is the fastest-growing plant known, but the genetics underlying this strange little plant's success long have been a mystery to scientists. A mult-investigator effort led by scientists from the Salk Institute for Biological Studies, La Jolla, Calif., is reporting new findings about the plant's genome that explain how it is able to grow so fast.

The research, published in Genome Research, will help scientists to understand how plants make trade-offs between growth and other functions, such as putting down roots and defending themselves from pests. This research has implications for designing entirely new plants that are optimized for specific functions, such as increased carbon storage to help address climate change.

"A lot of advancement in science has been made thanks to organisms that are really simple, like yeast, bacteria, and worms," says first author Todd Michael, research professor in Salk's Plant Molecular and Cellular Biology Laboratory. "The idea here is that we can use an absolutely minimal plant like Wolffia to understand the fundamental workings of what makes a plant a plant."

Wolffia, which is found growing in freshwater on every continent except Antarctica, looks like tiny floating green seeds, with each plant only the size of a pinhead. It has no roots and only a single fused stem-leaf structure called a frond. It reproduces similar to yeast, when a daughter plant buds off from the mother. With a doubling time of as little as a day, Wolffia could become an important source of protein for feeding Earth's growing population. (It already is eaten in parts of Southeast Asia, where it is...