User:Small.139/sandbox

Link to wikipedia addition: https://en.wikipedia.org/wiki/Talk:Communication

Wiki addition Quick change! Fungi produce hyphae and mycelia/mycelium. Right now it's spelled Marcelia, and is hyperlinked to the element Nobelium. Was there a reason for this?

Also, would you be interested in inserting the following paragraph into your section on plant communication? Plant communication and its evolution is something I recently did a project on, so I would like to contribute some of the information to this page.

'''Intercellular communication and plant developmental stages are mediated through hormones. The hormones are organized into six classes including auxin, gibberellin, cytokinin, ethylene, abscisic acid, and brassinosteroids. Sites of production vary depending on the hormones, as well as their corresponding receptors depending on the purpose.

When under stresses, such as extreme weather patterns or damage from pests, it is essential to trigger hormone responses quickly. Using the classic transportation methods, apoplastic and symplastic routes, complex hormone molecules move relatively slow. In 1983, University of Washington's zoologist, Dr. David Roades discovered how plants adapted in response to this slow moving transport system. Dr. Roades was studying insect damage patterns on the forest's willows, poplars, and sugar maples (Kat McGowan, 2013). Individual trees would show signs of damage, but not their neighbors. Further testing revealed that the trees under stress were releasing volatile organic compounds(VOC) into the air in order to quickly trigger an induced defense mechanism in all parts of the plant's aerial shoot. Neighboring trees were detecting the VOC from the plant under siege, and also began producing VOC due to an awareness of oncoming danger.

McGowan, Kat. "How Plants Secretly Talk to Each Other." Wired.com. Conde Nast Digital, 13 Dec. 2013. Web. http://www.wired.com/2013/12/secret-language-of-plants/.'''

Final Draft starts HERE

Plant Speech

AS8934 Tuesday, 9:10 AM

Communication: a system for transmitting or exchanging information according to the Merriam-Webster dictionary. It is human nature to pass down consequential stories to following generations. Evolution works much in the same way. Organisms take these experiences and signals from the environment, and use the memories to better defend themselves the next time a similar event occurs, leading to better adaptations to their specific niche. Observations in plant-to-plant relations have led to an expansion of a relatively new science. In respect to plants, information from the above definition can be substituted for "cues" that can be released by neighboring plants, triggering a morphological response in an individual plant. In simpler terms, plants are also communicating, and people have begun to take notice. What researchers have observed is that neighboring plants are listening in on the distress signals of individual plants and using it to their advantage. To better explain how plants are doing this, I will discuss basic plant behaviors, intracellular communication, plant defensive methods, and then finally examples of plant cueing in natural settings. The start of plant communications began at the University of Washington in 1983 (Kat McGowan, 2013). David Roades, a zoologist at the university, began to notice patterns in insect damage on the forest's willows, poplars, and sugar maples. What Dr. Roades found was that the trees had sensed the damage to the leaves, and in turn synthesized compounds that made the tree foliage unappealing to herbivores and stunted herbivore growth. Furthermore, the trees surrounding the attacked tree remained unharmed. Further testing revealed that the neighboring trees had also begun producing the protective compounds. Roades replicated his findings and released two papers. The credibility of his findings were damaged by a renowned ecologist of the time by the name of Dr. Lawton. He criticized the experimental design, claiming that disease must have spread throughout the insect test population. A 1990 journal aided in the recovery of the research's credibility. Washington State University's Dr. Farmer and Dr. Ryan experimented on hormone signaling between sagebrush and tomato. The journal convincingly proved that production and release of methyl jasmonate from tomato caused sagebrush to also produce methyl jasmonate. As persuasive as their extensive work was, it had yet to be replicated in the field. Dr. Richard Karban, of the University of California's Davis branch, is currently working on just that. Using sagebrush, Dr. Karban has successfully replicated Dr. Roade's observation of signal transference from one plant to another in the field. The study of plant behaviors is relatively new. Charles Darwin was the first to study it extensively in 1880 (Karban, 2008). He worked on plant growth patterns such as phototropism, gravitropism, and trophotropism. Phototropism is the directional growth of a plant's shoot (above ground organs) in regards to sunlight. Gravitropism describes the directional growth of both the shoot and root systems toward or away from gravitational forces. Thigmonasty is plant behavior in response to touch. The movements provided by these senses is entirely orchestrated by a careful communication of hormones among other variables. Auxin, gibberellin, ethylene, and other molecules cruise through the plant body conducting essential developmental stages such as germination and flowering. It is vital that these movements of hormones are quick to reach target areas, requiring rapid transportation from cell to cell. Without speed, the individual's fitness will drop due to over competition, predation, pathogen infection, and severe weather conditions. The rapid movement of the hormones is attributed to the amazing network of transport. Swift movement takes place in the vascular system of plant, but only after a procession through cramped cells. There are two means of doing so: apoplastic and symplastic. Apoplastic is the means of movement through cell walls. Symplastic movement takes water and ions on an alternate route through the plasmodesmata that connects all plant cells to each other, which is the main means of intercellular communication. As a new plant cell divides and a new cell wall forms, perforations form in the wall as some of the endoplasmic reticulum becomes trapped between the two cells. It is through this tunneling system that ions and lipid bodies may move through or around the endoplasmic reticulum. Once arriving at the casparian strip, the suberin (waxy) gateway to the vascular cambium, the hormones must make their way symplastically into the cells in order to pass into the vascular system. From there, the vascular system is a highway of water and nutrients that will carry the hormones throughout the plant. For bulky hormones, traveling through the cracks and crevices of cell walls is not the quickest route for cell to cell cues. Instead, for high priority situations, such as predation, plants came up with an aromatic method of signaling. In an emergency situation, the preferred network of communication is by volatile organic compounds (VOC) (Mescher, 2006). An attack in the leaf causes it to release volatiles into the air. These signals float to other cells in the body that then give off the same signal until the VOC reaches the target site. When this happens, the induced defenses are triggered. For pest control, it can cause growth stunting, stomach acidifying, or simply appear unattractive to the herbivore. The latter aspect is a commonly used method by herbs. The smelly vegetation used to flavor and decorate our meals, such as basil, develops their overpowering smells as a repellant against herbivores of all sizes. These are examples of continually produced defense which can be expensive to a plant. It has been discovered that neighboring plants will take advantage of sensing the plant's distress by then increasing its own defenses. By sensing its neighbors cues, plants are successfully defending themselves from receiving any damage. Plant to plant communication by means of VOC's have been found to work in two ways. One is to directly repel the immediate threat and the other is to attract the threat's own predators. (Karban, 2008). Another surprising means of communication has recently been discovered in Cuscuta pentagona and will be discussed later on in the paper. Dr. Karban of UC Davis has had decades of experience with plant signaling and its effects on the environment (McGowan, 2003). He works with sagebrush and it's ability for interspecies communication. Sagebrush has come up with an ingenious method of reducing competition around it by directly impacting the germination of competitor's seeds by using VOC's (Karban, 2008). The compounds also increase predatory defenses much in the way any herb would. Dr. Karban also studied the VOC communication taking place between sagebrush and other species, such as tomato and poplar. In the past, work was done to uncover how plants could possibly react so quickly to insect damage. Dr. Farm, in the 1990's, also worked on sagebrush, finding that causing damage anywhere on a plant causes an electric current to resonate from the damaged tissue to the rest of the plant (McGowan, 2003). This means of communication from within the plant body is reminiscent to an animal's central nervous system. An unpredictable discovery came out recently on Cuscuta pentagona, better known as dodder vine. The dodder vine is an intensely virulent parasitic plant in much of the world's agricultural systems, finding hosts on economically and culturally valuable crops. Better known as "witch's hair", dodder vine is a stringy plant, usually producing little to no chlorophyll, and detects its host by VOC released by the prey (Buffie, 2013). By nutational movements, or inherit rotational movement, the newly germinated dodder vine swings its way to the detected host and latches by means of trichomes and haustoria. Trichomes are "hairs" (modified epidermal cells) that can found on most plants. Haustoria are the globular feeding bodies that dodder vine inserts into the prey's plant cells. Once the haustoria has penetrated the cells, immense quantities of mRNA is transferred bidirectionally. In other words, mRNA moves from dodder to host, and from host to dodder vine (Kim, 2014). mRNA is thought to be an unstable information source, and so it was never thought that it could be transferred, and never at such levels. Further research is needed to interpret what is being communicated between C. pentagona and its host. In multicellular organisms, meiosis is fundamental to successful adaptation to everyday challenges. For example, imagine a bottleneck event, a random occurrence that unfortunately eliminates a population majority. The bottleneck event is a catastrophic flood that wipes out all but a few ferns in an isolated population. The remaining individuals are all females, making meiosis impossible. The only choice is to self fertilize, which will affect the future generation's genetic diversity. However, researchers at Nagoya University in Japan has found that Lygodium japonicum, Japanese climbing fern, is capable of gender change (Tanaka, 2014). Under the circumstance that there are only females in a population, females release VOC into the air, triggering gender changes for some individuals. This behavior is beneficial to the advancement of the genetic pool through isolation events. Volatile organic compound research has expanded much since its discovery in the 1980s. It has aided in the research in important agricultural components such as dodder vine invasion control methods, and plant health management against pests and pathogens. Technology is advancing in ways to help growers detect the distress calls of their crops (The Impact of Technology on Agriculture, 2013). With the addition of VOC studies, plant communities on a micro and macro scale can be better understood by researchers. Plant communication may also play a role in the evolution of ecosystems, the phenology of plant species, and the future of agricultural plant management.

References Colar, Angela. 2014. "Miniature gas chromatograph could help farmers detect crop diseases earlier." Georgia Tech News Center. Georgia Tech, 28 May 2014. Web. 29 Oct. 2014. http://www.news.gatech.edu/2014/05/28/miniature-gas-chromatograph-could-help-farmers-detect-crop-diseases-earlier. Karban, Richard. 2008. "Plant behaviour and communication." Ecology Letters. 11:727-739. Print. Kim, Gunjune, Megan L. LeBlanc, Eric K. Wafula, Claude W. dePamphilis, and James H. Westwood. 2014. "Genomic-scale exchange of mRNA between a parasitic plant and its hosts." Science. 345.6198:808-811. Science. Web. 29 Oct. 2014. McGowan, Kat. "How Plants Secretly Talk to Each Other." Wired.com. Conde Nast Digital, 13 Dec. 2013. Web. 29 Oct. 2014. http://www.wired.com/2013/12/secret-language-of-plants/. Mescher, Mark C, Justin B. Runyon, and Consuelo M. De Moraes. 2006. "Plant host finding by parasitic plants." Plant signaling & behavior. 1.6:284-286. Print. Sci-News. "Biologists discover new form of plant communication." Sci-News. Sci-News, 15 Aug. 2014. Web. 29 Oct. 2014. http://www.sci-news.com/biology/science-new-form-plant-communication-02103.html. "The impact of technology in agriculture." Invested Development. Invested Development, 13 June 2013. Web. 29 Oct. 2014. http://investeddevelopment.com/blog/2013/06/the-impact-of-technology-in-agriculture/. Buffie, Erna. What Plants Talk About. PBS, 2013. Film. Tanaka, Junmu. 2014. "Antheridiogen determines sex in ferns via a spatiotemporally split gibberellin synthesis pathway". Science. 346:469-473. doi: 10.1126/science.1259923