Karrikin 2, found in smoke water extracts, acts as a key germination trigger for many species from fire-prone Mediterranean climates, but is also active in plants from temperate regions. Karrikin 2 is more active than karrikinolide and KAR3 in promoting the germination response of Arabidopsis (PD Ler ecotype) seeds, at concentrations as low as 10 nM.
Flematti GR (2009) Identification of alkyl substituted 2H-furo[2,3-c]pyran-2-ones as germination stimulants present in smoke. J. Agric. Food Chem. 57:9475