Op#cal Study of Plant System Poten#al

Transcription

1 Op#cal Study of Plant System Poten#al Douglas Janssen 1, Mohammad Islam 2, David Chao 3, Jerry Gu 4, David Eisen 2, Fow-Sen Choa 2 1 Greater Grace Christian Academy, 6063 Moravia Park Drive, Baltimore, MD 21206, USA 2 University of Maryland Baltimore County, Dept. of CSEE, 1000 Hilltop Circle, Baltimore, MD National Sun Yat-Sun University, Department of Biological Science, Kao-shiun Taiwan, ROC 4 Marriotts Ridge High School, Woodford Drive, Marriottsville, MD 21104, USA choa@umbc.edu

2 Research Motivations Imagine field-deployed MIRTHE sensor networks powered by sustainable plant-sourced energy We aim to Develop sustainable power harvesting from live plants Can we generate power using plant sections Further fundamental understandings of plant electrophysiology & photon/plant cell interactions

3 Fundamental Research Aims 1. Investigate Electrical Polarity in Plants: Discover how the electrical properties of individual plant cells and groups of plant cells contribute to system voltage polarity changes within plants. Understand complex bio-circuitry present in plants, utilizing circuit modeling and direct contact measurements. Investigate the effect of external (ie. light) stimuli on intracellular conditions, and resulting polarity changes. 2. Investigate Photon Plant Cell Interactions: Use a variety of wavelengths extending from UV through Mid-IR to probe electrical response in plant tissues. And Harvest plant-sourced electricity for potential uses such as powering remote MIRTHE sensor systems in the field.

4 Previous Work in Electrophysiology Mid-IR laser stimulation of Dionaea muscipula (Venus fly trap) D. Eisen, D. Janssen, X. Chen, F-S. Choa, D. Kostov, and J. Fan, Trap Closure of Venus Flytrap via Mid-IR Stimulation, Biomedical Engineering Society Annual Meeting, paper:p-sat-b-29, Atlanta, GA, Oct , > Multi-wavelength study, laser stimulation of insect a n d a n n e l i d n e r v o u s systems using customm a d e m i c r o s u r g e r y p l a t f o r m r e v e a l e d sensitivity of biological circuitry to laser pulses. Optical power dependence of system potential spiking in black soldier fly Hermetia illucens.

5 Investigating Plant Electrophysiology Environmental study Electrical contact was established with old-growth woody trees at various locations along the sap transport system. Physical and broadband IR source stimuli can generate electrical signal when occurring along the same conduction pathway as sap, suggesting a relationship. Stimuli resulted in measured biopotential change was from ~336 mv to ~325 mv. From: Douglas Janssen, Mohammad Islam, David Chao, Jerry Gu, David Eisen, Fow-Sen Choa, "Electricity derived from plants", International Conference & Exhibition on Clean Energy, Ottawa, Canada, Sep. 9-11, 2013.

6 Investigating Plant Electrophysiology: Polarity E v e r y w o o d y p l a n t section, in thicknesses ranging from 2 mm to 1 m exhibited the same polarity when tested s h o r t l y a f t e r b e i n g r e m o v e d f r o m t h e environment, with: top + / bottom - following system fluid flow. This may also be related to voltage-gated ion p u m p s i n t h e c e l l membranes.

7 Investigating Plant Electrophysiology: Lessons 1. Making stable electrical contact with living plant material is challenging, as plants possess complex bio-circuitry. Electrical polarity has been observed to shift, with specific causes still under investigation. 2. Plant system potential polarity follows the conduction pathway of fluids. 3. Bioelectric potentials are insensitive to length, as thin sections may produce as much electrical current as longer samples, but lifetimes are proportional to length. 4. Cascading plant sections can result in accumulation of potential up to ~0.8-2V output, with current capable of reaching ~40-50uA.

8 Investigating Plant Electrophysiology: Stimuli Laser stimulation of plant vascular tissue caused system potential changes. Right: 820nm laser illumination, 120 mw, targeting xylem tissue of Acer negundo. System potential changes in Schefflera arboricola when isopropyl alcohol is added to leaf along conduction pathway. Physical / chemical stimuli are known to initiate transient changes in biopotential. Some plants exhibit wavelength and temperature-dependent response

9 Conclusions 1. Preliminary findings illustrate various stimuli (ie. laser illumination) may have an effect on intracellular conditions but do not result in electrical polarity changes. It is likely that shifting electrode positions are responsible for polarity reading switching in most samples. 2. Electrical polarity consistently follows intercellular fluid flows in herbaceous and woody plant vascular tissues. Preliminary tests reveal groups of plant cells (ie. growth rings in woody plants) contribute to system voltage polarity changes within plants. 3. Optical stimulation of plant tissue can temporarily increase system potential voltages; we propose by interaction with cell conditions & iongated cell membrane pumps. 4. Plants possess bio-potential that, as a result of ongoing research effort, may be safely and sustainably harvested for use in powering low-drain devices such as MIRTHE environmental sensor networks.

10 References: [1] Burdon-Sanderson J. Note on the electrical phenomena which accompany irritation of the leaf of Dionaea muscipula. Proc R Soc. Lond 1873;21: [2] Darwin C. Insectivorous plants. London: Murray; [3] Volkov AG, ed.. Plant electrophysiology. Berlin: Springer; [4] D.S. Fensom, The bioelectric potentials of plants and their functional significance: Some daily and seasonal changes in the electrical potential and resistance of living trees, Can. J. Bot. 41 (1963) [5] J.L. Thony, P. Morat, G. Vachaud, J.-L. Le Moue l, Field characterization of the relationship between electrical potential gradients and soil water flux, C.R. Acad. Sci. Paris 325 (1997) [6] P. Morat, J.-L. Le Moue l, A. Granier, Electrical potential on a tree. A measurement of the sap flow? C.R. Acad. Sci. Paris 317 (1994) [7] Opritov V.A., Retivin V.G., On the mechanism of propagating excitation in higher plant,. Fiziol Rast 29: , 1982 [8] D. Eisen, D. Janssen, X. Chen, F-S. Choa, D. Kostov, and J. Fan, Trap Closure of Venus Flytrap via Mid-IR Stimulation, SPIE Photonics West, San Francisco, California, 2-7 Feb [9] Hartman E, Influence of light on the bioelectric potential of the bean (Phaseolus vulgaris) hypocotyl hook, Physiol Plant, 33: , [10] Dominique Gibert, Jean-Louis Le Moue, Luc Lambs, Florence Nicollin, Frederic Perrier, Sap flow and daily electric potential variations in a tree trunk, Plant Science, 171, p , [11] Doug Janssen, Mohammad Islam, David Chao, Jerry Gu, David Eisen, Fow-Sen Choa, "Electricity derived from plants", International Conference & Exhibition on Clean Energy, Ottawa, Canada, Sep. 9-11, [12] Dominique Gibert, Jean-Louis Le Moue, Luc Lambs, Florence Nicollin, Fre de ric Perrier, Sap flow and daily electric potential variations in a tree trunk, Plant Science 171, pp , (2006) Please visit poster #56 This material is based upon work supported by the National Science Foundation under Grant No. EEC