Trace gas emissions and smoke-induced germination

Jon E. Keeley; C. J. Fotheringham

doi:10.1126/science.276.5316.1248

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Trace gas emissions and smoke-induced germination

Jon E. Keeley·C. J. Fotheringham

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Abstract

Dormant seeds of a California chaparral annual were induced to germinate by smoke or vapors emitted from smoke-treated sand or paper. Nitrogen oxides induced 100 percent germination in a manner similar to smoke. Smoke-treated water samples inducing germination were comparable in acidity and concentration of nitrate and nitrite to nitrogen dioxide (NO 2 )–treated samples. Vapors from smoke-treated and NO 2 -treated filter paper had comparable NO 2 flux rates. Chaparral wildfires generate sufficient nitrogen oxides from combustion of organic matter or from postfire biogenic nitrification to trigger germination of Emmenanthe penduliflora . Nitrogen oxide–triggered germination is not the result of changes in imbibition, as is the case with heat-stimulated seeds.

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Jon E. Keeley, C. J. Fotheringham. 1997. Trace gas emissions and smoke-induced germination. https://doi.org/10.1126/science.276.5316.1248

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