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BD Now! Fwd: Plant Neurobiology Sprouts Anew: The Secret Life of Plants in The Scientist

>Status:  U
>Delivered-To: aballiett@frontiernet.net
>Date: Mon, 25 Jul 2005 17:01:16 -0700
>Subject: Plant Neurobiology Sprouts Anew: The Secret Life of Plants in The
>	Scientist
>From: Shannan & James Johnson <shanjam@igc.org>
>To: recipient list <shanjam@igc.org>
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>Can this first symposium in Germany which focuses on attributing
>intelligence to the vegetative begin a revolution in this country's
>universities? Please pass on to other university staff. For an amazing video
>on the effects of light on the growth of plants, scroll down to the bottom
>of this email and check out EXPLORING THE SPECTRUM. Dr. John Nash Ott did a
>lot of the tedious time-lapse photography in the old Disney movies.
>Quantum Agriculture researchers are still at it picking up where the plant
>pioneers or bioneers left off! Stay tuned for Plant Signaling and Behavior
>journal due out in 2006.
>The word neuron was coined by German scientist Heinrich Wilhelm Gottfried
>von Waldeyer-Hartz in 1891 and originates from the Greek meaning string or
>sinew according to the Oxford English Dictionary. Franti sek Balu ska says
>the word comes from the Greek meaning vegetal fiber. "Maybe it's time to
>steal it back."
>Plant Neurobiology Sprouts Anew
>The Scientist
>A nascent field copes with an identity crisis
>By Trevor Stokes
>A meeting this past May ushered in the birth, or perhaps rebirth, of a field
>of study in which the controversy starts at the very name. Frantisek
>Baluska, of the University of Bonn, Germany, coorganized the First Symposium
>on Plant Neurobiology, calling the field a "new view of plants" that
>combines physiology, ecology, and molecular biology.1
>Neuroscientists won't likely worry about plant scientists encroaching on
>their territory, but the name does make some uneasy. "It's more a problem
>with the green party than the red party," quips Dieter Volkman, also at
>University of Bonn. Not the least because some scientists have pushed the
>boundaries in attributing intelligence to the vegetative. Tony Trewavas,
>professor in plant biology at the University of Edinburgh, argues, "The
>basics of intelligence are not to be found in reasoning, shrewdness, and
>other similar terms, but it is instead the capacity for problem solving,
>something that virtually all organisms have to do."
>But Baluska and the meeting's other organizers presented many tantalizing
>comparisons between plants and animals, suggesting that they may share
>neurological-like qualities. Plants use electrical signaling such as action
>potentials for cell-to-cell communication; they also use signaling molecules
>and processes similar to those in nervous systems. Plants can obtain,
>process, store, and transmit information, and they can live in complex
>Though the name may be controversial, most scientists involved thought that
>the meeting was a good and timely idea. For many researchers, it was a time
>to dust off old observations and to set up new collaborations. For example,
>scientists researching glutamate receptors in plants for many years "came
>together for the first time," according to Volkman. Susan Murch, program
>officer of science based medicinal plants at the University of Guelph says
>the meeting was "less a meeting presenting current results, more about
>results that span 20 years." For some it's an idea whose time has come.
>Though the observation that plants have electrical signaling is more than a
>century old (see below), scientists are still uncertain as to what
>electricity is doing to plants. Alain Vian of Blaise Pascal University in
>Claremont, France, presented unpublished work showing one of the first
>direct biological consequences of electrical fields like those found in the
>modern environment. Unlike animals, plants have two types of electrical
>signaling. Action potentials, involving membrane depolarization, act at high
>speeds (1 cm/sec) and have a refractory period. Variation potential (called
>slow wave in Europe) is a systematic electrical signal that occurs more
>slowly (1 mm/sec) in plants.
>Using an electromagnetic source similar to cell phones, Vian found that the
>"weak stimulation is able to evoke gene expression of stress-related genes."
>By exposing one leaf and shielding the rest of the plant, "there is a
>transmission of stimulus from the stimulated leaf to the shielded leaf."
>Independent research from Hillel Fromm at Tel Aviv University, Israel,
>suggests that the "phloem serves as a communication of electrical signals
>over long distances." Vian notes that unlike controversial studies
>associating brain cancer with cell phone use, this is an example of a
>tractable biological response from electromagnetic doses found in our
>present surroundings.
>It's been known for some time that plants contain neurotransmitter machinery
>similar to animals, such as glutamate receptor-like genes (GluRs). In
>animals, glutamate is the major excitatory neurotransmitter in their central
>nervous systems. So far little is known about the function of GluRs in
>Arabidopsis, where they were originally identified, but external application
>of glutamate can depolarize roots and cause ionic influxes, analogous to
>neurons.2 Nevertheless Fromm notes, "What was missing [at the meeting] was
>the connection between electrophysiology and neurotransmitters."
>In animals, synapses connect nerve cells and are where the vesicle-mediated
>transport of neurotransmitters occurs. Originally thought to be unique to
>neurons, immunological researchers now describe signaling between T
>lymphocytes and antigen-presenting cells (APCs) as occurring through
>synapses.3 Translated to plants, some scientists propose that auxin, a
>plant-specific hormone, may shuttle through vesicles between plant cells.
>Researchers have shown that PIN1, crucial to auxin transport, cycles between
>the basal plasma membrane and the intracellular spaces. However, Ottoline
>Leyser, a geneticist at the University of York who studies auxin, says, "The
>comparison with synapses I think is pretty weak. Most people agree that the
>[PIN1] cycling happens. There is no evidence at all that vesicles transport
>auxin or for vesicles grabbing the auxin at the other side." Leyser suggests
>that uptake of auxin occurs through either diffusion or the AUX family of
>proteins. However, she notes "The direction [of auxin transport through
>tissues] is mostly driven by efflux."
>Plant neurobiology may raise awareness that, though plants cannot move, they
>actively monitor and react to their biotic and abiotic environments,
>analogous to social animals. Velemir Ninkovic (Swedish University of
>Agricultural Sciences, Uppsala, Sweden) presented evidence that plants use
>volatiles to communicate with each other to "identify competitors and then
>change growth strategy." Even if a plant has a lower biomass due to a
>competitor, "leaf area increases in the plant which can support higher
>physiology," which compensates for the smaller size. Research to identify
>the chemical composition of these volatiles is ongoing.
>Many questions still need to be addressed about how plants process
>information from the environment to optimize growth. While scientists alter
>one condition at a time, "cells in the real world respond to all things at
>once," notes Baskin. "How does a plant respond to its environment in a
>coherent way without a central processor?" asks Mott.
>But as the multidisciplinary field comes to fruition, some remain uncertain
>that the name will stick. Keith Mott of Utah State University says, "In my
>opinion it [the title] was a mistake because of the animal connotations. In
>the end I don't think it [the field] will get called plant neurobiology."
>Indeed, starting in January 2006, Landes Bioscience will begin publishing
>Plant Signaling and Behavior, a peer-reviewed quarterly journal.4 The title
>suggested by the publisher, Plant Neurobiology, was eventually rejected
>because of an E-mail discussion among 20 to 25 symposium participants. While
>some have trepidations about the title, others just find it insulting. Peter
>Neumann, chair of agricultural engineering at Technion-Israel Institute of
>Technology, says, "Plants are unique. There is no reason to take creatures
>that are autotropic and call them demi-animals." Leyser agrees, adding,
>"Multicellularity evolved completely independently in plants and animals.
>There is no reason to think that they would solve the problems in the same
>1. F Baluska et al, "Plant synapses: actin-based domains for cell-to-cell
>communication," Trends Plant Sci 2005, 10:  106-11. [PubMed
>Abstract][Publisher Full Text] 
>2. KL Dennison, EP Spalding "Glutamate-gated calcium fluxes in Arabidopsis,
>" Plant Physiol 2000, 124:  1511. [PubMed Abstract][Publisher Full Text] 
>3. P Friedl, J Storim "Diversity in immune-cell interactions: States and
>functions of the immunological synapse," Trends Cell Biol 2004, 14:  557-67.
>[PubMed Abstract][Publisher Full Text] 
>4. http://www.landesbioscience.com/journals/psb/index.php  
>Repeating History?
>Plant neurobiology marks the third broad historical opportunity for
>scientists to ponder seriously the role of electrical signaling in plants.
>Action potentials in plants date back to 1873, when J. Burdon Sanderson
>published his observations on the "electrical phenomena" in Venus fly traps.
>Later, in 1896, Charles Darwin wrote about experiments demonstrating the
>"transmission of the motor impulse" in the same plant species. Ultimately,
>research into electrical signaling flourished in animals and withered in
>One hundred years after Sanderson's publication, under the guise of
>electrophysiology, Barbara Pickard of Washington University in St. Louis
>wrote an academic review that might have ushered in a new era.1 In the
>paper, she writes, "The emerging notion that all higher plants might utilize
>electrical signals in coordinating a variety of daily functions seems ripe
>for closer examination." But that same year, Peter Tompkins and Christopher
>Bird published The Secret Life of Plants, which concluded that electrical
>activity in plants points to the hidden emotional lives of
>photosynthesizers.2 The effect was devastating to the nascent field.
>Thirty years later, the field has been expanded, renamed, and repackaged as
>part of plant neurobiology. Some scientists fear that plant neurobiology's
>name may backfire, sending plant electrophysiology back into the woodwork.
>Eric Davies of North Carolina State University writes via E-mail: "Those in
>favor (believers) say that "neuro" is a plant word for fiber stolen by the
>animal people. Those opposed (atheists) worry about the 'Secret Life'
>syndrome. Some of those uncertain (agnostics) delight in the provocative
>title, but worry about being cast aside by the mainstream yet again."
>The title won't do much harm, says Peter Barlow of the University of
>Bristol, UK, who writes: "I doubt that there will be the 'backlash.' People
>in science are much more open-minded nowadays, partly because science has
>become so diverse and so many unexpected discoveries have come about." Tony
>Trewavas at the University of Edinburgh takes a more pragmatic position:
>"Most plant biologists are open to new concepts. If they find the concepts
>useful, they will survive, if they don't, it will simply disappear."
>1. BG Pickard "Action potentials in higher plants," Bot Rev 1973, 39:
>2. P Tompkins, C Bird The Secret Life of Plants New York: Harper & Row
>EXPLORING THE SPECTRUM: The effects of natural and artificial light on
>biological processes and health, by Dr. John Nash Ott, founder and former
>director of the Environmental Health and Light Research Institute, Sarasota,
>Florida. Dr. Ott pioneered in the science of photobiology and discovered the
>profound effects that qualities of light have on living organisms. He was
>the first to recognize and document the harmful effects of fluorescent
>lights on both plants and animals. His astounding time-lapse photography
>shows that variations in periodicity, intensity and wavelength distribution
>of light energy control certain plant growth processes such as the setting
>of buds, opening of flowers, determination of sex and maturing of fruits.
>This video shows the effects of different colors of light on living
>organisms even down to the the cellular level. Dr. Ott's investigations into
>the effects of fluorescent lights on hyperactivity and cancer among school
>children are milestone environmental and health discoveries. This video
>drives home the observations made by Dr. Ott in his critical book Health &
>Light (described in the "Bioenergy..." section of this catalog). 80 min.
>1/2" VHS. NTSC
>  $29.95 Videotape (European PAL format available upon request)
>The Quantum Agriculture Project
>2555 Mark West Station Road
>Windsor, CA  95492
>QAP updates are devoted to scientific investigation into agriculture
>systems, issues, practices and associated energy phenomenon.


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