Smoke Chemical Shown to Increase Germination

Plant biologists, who have long known that a compound in smoke causes many seeds to sprout, have now isolated the specific chemical -- a finding that could help boost crop yields and preserve rare plants.

The study, published Friday in the journal Science, describes the structure and synthesis of a compound called a butenolide, a component of smoke.

Scientists at the University of Western Australia tested the chemical on seeds from lettuce, tobacco and 14 wild plants. They showed that it dramatically increased the number of seeds that sprouted.

The chemical could help biologists cultivate endangered plants that require fire to sprout -- without resorting to actual fires. It could also make farming more cost-effective because the compound increases the germination rate for many crops, even if they do not require fire.

“There’s potentially a whole new way that everyone -- from the botanist to the vegetable grower -- could get a benefit,” said Kingsley W. Dixon, science director at Kings Park and Botanic Garden in Perth, Australia, and a coauthor of the study.

Biologists think many seeds evolved to respond to fire, which might signal the availability of more space and light to grow. Some seeds, like those from sequoias, almost never sprout without this signal.

“The real power of this discovery is going to be in the management of wild lands,” Dixon said.

Seeds from species like lettuce are also sensitive to fires and germinate about twice as often when watered with even low concentrations of the chemical, the researchers found.