Trace gas production for rapid non-destructive determination of seed viability

Seed viability, the most important factor in determining seed quality, is tested by destructive means that can take anywhere from 24 hours for assays for enzyme activity to as many days as it takes for the seed to actually germinate. We used cabbage (Brassica oleracea) and onion (Allium cepa) seeds as model systems for determining viability based on comparisons of gaseous emissions by intact control, naturally- and artificially-aged seeds, both with and without imbibition. Volatiles were monitored from imbibing seeds after 0.5 to 3 hours of accumulation. Dry seeds were sealed in vials for up to 20 hours before measurement of accumulated gases. Ethane, ethylene, acetaldehyde, and ethanol were measured in the range of pl/g by laser-based photoacoustic spectrometry, while CO2 was measured by infra-red absorption in the nl/g range. Ethane production, a marker for lipid peroxidation of membranes, decreased in proportion to seed age and germinability. Ethylene and acetaldehyde production increased in proportion to degree of seed ageing, while CO2 production decreased in aged seeds compared to non-aged controls, and ethanol production was not consistently related to ageing.