Smoke awakens some seeds with cyanohydrins

Just as the mythical phoenix rises from its own ashes, smoke from a forest fire can stimulate the seed germination needed to bring a burned-out forest back to life. Researchers in Australia have determined that glyceronitrile, one of the thousands of compounds present in smoke from burning vegetation, may be spurring certain seeds into action (Nat. Commun., DOI: 10.1038/ncomms1356). The discovery, made by the University of Western Australia’s Gavin R. Flematti and coworkers, could help scientists and farmers awaken dormant seeds. In 2004, Flematti identified a different compound, later dubbed karrikinolide, as the chemical in smoke responsible for making some seeds sprout (C&EN, April 12, 2010, page 37). But one iconic Australian plant—Anigozanthos manglesii, commonly known as the red and green kangaroo paw—did not respond to the compound even though its seeds were known to germinate when exposed to smoke. So Flematti’s search continued until he discovered that glyceronitrile, as well as several other cyanohydrins, could awaken A. manglesii and some other smoke-sensitive seeds. Flematti believes that the cyanohydrins act by releasing cyanide, which is known to stimulate seed germination.