Emeritus Prof. Steven M Smith
Emeritus Professor of Plant Genetics and Biochemistry
Discipline of Biological Sciences
School of Natural Sciences
University of Tasmania
I study the role of chemicals produced by the combustion of vegetation on post-fire seed germination and landscape regeneration. Germination of the soil seed-bank following fires is a key component of the revegetation process. Many chemicals produced by fire inhibit seed germination but there are others that can stimulate seed germination. The best understood, and probably most active stimulants, are known by the common family name of ‘karrikins’ (derived from ‘karrik’, a Noongar word for smoke). These are low molecular weight compounds containing pyran and butenolide rings (https://en.wikipedia.org/wiki/Karrikin). My research resulted in the discovery of the karrikin receptor protein in plants and to an understanding of how the karrikin response evolved. Other germination stimulants are cyanohydrins such as glyceronitrile, which breaks down in the soil to release a small amount of cyanide. Knowledge of the chemicals produced or removed by wildfires, and of their effects on soil biota will be vital to understanding how best to manage fuel and fires in the future. Such chemicals are also very useful in restoration ecology and plant conservation work.