The paper may be found here, although most of it is behind a Paywall, but they did provide a video and some graphics illustrating the signaling process does indeed exist by means of electrodes which reveal on the graph that indeed some type of electrical signaling was going on. Who would have thought that caterpillar merely walking across a leaf offered no response, but actually cutting the leaf would send an electrical alarm signal spreading at 9 cm per minute when eaten. Someone has uploaded the video on YouTube, but I'll post a chart and link below of the video from Nature's site. It is helpful to full-screen the video (which may do so in the link automatically) to watch both the actual image of the caterpillar interacting with the leaf and the electrical graphs which show an actual electrical response simultaneously.
Nature Video: Plant Biology: Electrical Defense Response
(click to enlarge image)
Such signaling may also help us to better explain and/or understand how and why plants release VOCs (aerosols) & electrical ions under certain specific environmental conditions into our Earth's atmosphere which enhances cloud formation and rainfall. The question is, how or what does the trigger releasing for this signal ? Especially is this important with regards 'Climate Change' as many still do not find a connection between healthy old growth vegetation on Earth and it's influence in moderating Earth's climate driving machine which itself is created from physical mechanisms regarding our planet Earth. It is true, Storms develop and move from off the Earth's Oceans and move over the dry land, but what their eventual outcome potential will be over the landscape may well depend on how healthy and functional the healthy vegetation is on the surface. We know that desertification has resulted from vegetation removal in many areas of the Earth. I personally have seen summer monsoonal changes with respect cloud formation with the removal of chaparral plant communities from a specific area. A friend of mine originally from Kenya Africa told me yesterday that the common illiterate people of the rural countryside there completely cut down the forests for their fuel wood or the manufacture of Charcoal for European Bar-B-Q grill coals industry. They are not knowledgeable enough to understand that you need to replant. The horrific result has been more and more disruption in rainfall patterns. Well, how could that be ? After all, are not storms only clouds formed over oceans and moving over land masses dumping their contents - Right ? No, there is far more and people everywhere need to get this through their heads. The only way I can further explain the fine tuning influences vegetation plays in it's role of weather moderation is using a Car's Engine as a comparison.
To understand and appreciate how fractions of a degree can make a huge difference in climate, please watch the documentary on "Global Dimming" where a researcher, who after the no flight pattern was ordered after the 911 attacks on the World Trade Towers, proceeded to measure the temperature changes in the atmosphere which changed by a mere 1 degree after no flights were over North America for almost a week.
|Meteo Systems International AG|
What's sad is that mankind has through their obsession with consumerism (among other disruptive motives or actions), has reverse engineered our planet's natural systems either knowingly or unknowingly in seeking the Earth's natural resources to drive their economic engines and it's only now after certain of these natural components are missing that we understand and feel their loss to the entire system. Whether or not people actually get this is irrelevant. The natural system has worked this way for countless thousands of years and it should be respected. It's a sort of, "If it's not broken why fix it" scenario. No amount of artificial weather modification is going to replace what is the reality. Unfortunately, the information on all of this is compartmentalized separately by Scientists working in various specialized fields. But they really need to dump their tunnel vision of focus or field of interest and come together with others of varying backgrounds in cooperation and sharing their research findings from their respective fields with one another if they truthfully want to get a handle on this phenomena known as 'Climate Change'. Of course we don't live in that type of cooperative world globally, although some may be open to the idea locally. But the Earth is going to reach a point of no return where all the reverse engineering itself may reach a point of not being able to being put back together again. Makes me think of my brother who dismantled my HO scale Diesel Electric locomotive to find out how it worked, only to be incapable of putting it back together again. But I have a feeling things will not be allowed to reach that point. What do you think ?
"System Potentials, a Novel Electrical Long-Distance Apoplastic Signal in Plants, Induced by Wounding" (2009)