Trace gas analysis for rapid non-destructive determination of seed viability
Joshua D. Klein, Edi Santosa, lulia Boamfa, Yonit Hebbe and Frans Harren
ISHS Acta Horticulturae 631: 2004. pp. 39-42.
2002
บทคัดย่อ
Seed viability,the most important factor in determing seed quality, is tested by destructive means that can take anywhere from 24 hours for assays for enzyme activity in the embryo to as many days as it takes for the seed to actually germinate. We used onion seeds as a model system for determinigh viaibility based on comparisons of gaseous emissions by intact control, naturally-and artificially-aged seeds, both with and without imbibition. It is generally considered that seeds that have been imbibed for less than six hours can be dried and re-stored without incurring damage. Bolatiles from imbibing seeds were sealed in vials for 10-18 hours before measurement of accumulated gases. Ethane, acetaldehyde, and ethanol were measured in pl/g by laser-based photoacoustic spectrometry, while CO2 was measured in nl/g by infra-red absorption. Ethane production, a marker for lipid peroxidation of membranes, decreased in proportion to seed age and germinability, and also decreased during the first 5 hours of seed imbibition. CO2 production was enhanced in aged seeds compared to non-aged controls, in both dry and imbibed seeds. Acetaldehyde production increased sharphy, compared to ethanol, during initial imbibition of aged seeds, although ethanol production increased strongly after 2-3 hours of imbibition. Similar results were obtained in wheat, tomato, and chickpea seeds. Monitoring of trace gases from intact seeds appears to be a rapid and non-destructie means of determining seed viability. This work was supported by the European Community-Access to Research Infrastructures action of the lmprovign Human Potential Programme.