The hazy smoke lingering after forest fires contains chemicals that summon the forest back to life — and now are emerging as a potential new generation of agricultural chemicals that could boost food crop production and revitalize barren soil. Those biochemical signaling molecules, which stimulate the plant growth, are the topic of an article in the current issue of Chemical & Engineering News (C&EN), ACS’ weekly newsmagazine.
C&EN Senior Editor Bethany Halford notes that smoke’s ability to spur the growth of seeds after a forest fire first caught the attention of scientists 20 years ago. Scientists in Australia in 2004 finally identified the first smoke-derived chemicals responsible for promoting the germination of seeds. Named “karrikins,” after the Aboriginal word for smoke, these substances trigger seed sprouting and foster seedling growth. They help explain the incredible ability of fire-ravaged landscapes to spring back to life.
Studies now show that karrikins speed the growth of corn, tomatoes, lettuce, and other food crops and help crops tolerate a wider range of temperatures. They have “tremendous” invigorating properties, enabling seeds stored for years to grow as if young. The article points out that scientists in Australia already are using karrikins on a limited basis to restore vegetation to land stripped bare during mining of aluminum ore. Wider use depends on development of ways of producing large amounts of karrikins at low cost, the article notes.