The effect of hydrostatic vs. shock pressure treatment of plant seeds

• Published in: Journal of physics. Conference series 2014-05, Vol.500 (18), p.182025-6
• Main Authors: Mustey, A, Leighs, J A, Appleby-Thomas, G J, Wood, D C, Hazael, R, McMillan, P F, Hazell, P J
• Format: Article
• Language: English
• Subjects: Bacteria; Correlation; Cut-off; Cylinders; Data collection; Gas guns; Germination; Hydrostatic pressure; Lettuces; Panspermia; Physics; Seeds
• ISSN: 1742-6596; 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/500/18/182025

The hydrostatic pressure and shock response of plant seeds has been investigated antecedently, primarily driven by interest in reducing bacterial contamination of crops and the theory of panspermia, respectively. However, comparisons have not previously been made between these two methods ofapplying pressure to plant seeds. Here such a comparison has been undertaken based on the premise that any correlations in collected data may provide a route to inform understanding of damage mechanisms in the seeds under test. In this work two varieties of plant seeds were subjected to hydrostatic pressure via a non-end-loaded piston cylinder setup and shock compression via employment of a 50 mm bore, single stage gas gun using the flyer plate technique. Results from germination tests of recovered seed samples have been compared and contrasted, and initial conclusions made regarding causes of trends in the resultant data-set. Data collected has shown that cress seeds are extremely resilient to static loading, whereas the difference in the two forms of loading is negligible for lettuce seeds. Germination time has been seen to extend dramatically following static loading of cress seeds to greater than 0.4 GPa. In addition, the cut-off pressure previously seen to cause 0% germination in dynamic experiments performed on cress seeds has now also been seen in lettuce seeds.