Biomimetic measurement of allelochemical dynamics in the rhizosphere

• Published in: Journal of chemical ecology Vol. 31; no. 2; pp. 221 - 236
• Main Author: Weidenhamer, J.D
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01.02.2005; Springer Nature B.V
• Subjects: allelopathy; analysis; Animal and plant ecology; Animal, plant and microbial ecology; Autoecology; Benzoquinones; Benzoquinones - analysis; Biological and medical sciences; biomimetic extraction; Biomimetic Materials; Biomimetic Materials - chemistry; Biomimetics; chemistry; Chromatography, High Pressure Liquid; Dimethylpolysiloxanes; Dimethylpolysiloxanes - chemistry; Enzyme Inhibitors; Enzyme Inhibitors - pharmacology; extraction; Fundamental and applied biological sciences. Psychology; General aspects; growth & development; Lipids; Lipids - analysis; Liquid chromatography; Measurement; pharmacology; Pheromones; Pheromones - analysis; Pheromones - chemistry; Pheromones - pharmacology; Photosynthesis; Plant communities; Plant Extracts; Plant Extracts - chemistry; Plant Roots; Plant Roots - chemistry; Population Dynamics; quantitative analysis; Rhizosphere; root exudates; Silicones; Silicones - chemistry; Soil solution; Sorghum; Sorghum - chemistry; Sorghum - growth & development; sorgoleone; stir bar sorptive extraction; Thin films; Time Factors; Monocotyledones; biomimetic extraction; polydimethylsiloxane; Allelopathy; Method; Allelochemicals; matrix-SPME; Rhizosphere; sorgoleone; Gramineae; Angiospermae; Spermatophyta; Fodder crop; Sorghum bicolor x Sorghum sudanense; rhizosphere chemistry; stir bar sorptive extraction; Methods
• ISSN: 0098-0331; 1573-1561
• DOI: 10.1007/s10886-005-1337-x

Polydimethylsiloxane (PDMS) materials were used to quantify levels of the photosynthesis inhibitor sorgoleone in the undisturbed rhizosphere of sorghum plants. The materials used included stir bars coated with PDMS (stir bar sorptive extraction), technical grade optical fiber coated with a thin film of PDMS (matrix-solid phase microextraction), and PDMS tubing. PDMS tubing retained the most sorgoleone. As analyzed by high performance liquid chromatography, amounts of sorgoleone retained on the PDMS materials increased with time. Other materials tested (polyurethane foam plugs, C18 and Tenax disks, and resin capsules) proved less suitable, as they were subject to sometimes extensive penetration by fine root hairs. These results demonstrate the potential for PDMS-based materials to monitor the release of allelochemicals in the undisturbed rhizosphere of allelopathic plants. Unlike extraction procedures that recover all available compounds present in the soil, PDMS functions in a manner more analogous to plant roots in sorbing compounds from soil solution or root exudates. Information on chemical dynamics in the rhizosphere is crucial for evaluating specific hypotheses of allelopathic effects, understanding allelopathic mechanisms, and assessing the importance of allelopathic processes in plant communities.