Building on knowledge first discovered in the 1980s, scientists at Japan's Saitama University discovered that plants emit signals to warn nearby plants of threats — such as animals destroying them. The research team led by Yuri Aratani and Takuya Uemura used real-time imaging to monitor plants' response to these signals. The research focused on tomato plants and Arabidopsis thaliana, a common herbaceous plant that has been genetically modified to display a green fluorescent signal in response to an influx of calcium ions. By the way, the influx of calcium ions is a universal means of cellular communication. Based on experiments, when these plants are exposed to distress signals from other plants attacked by caterpillars, they react with a calcium signal. Researchers have identified two specific compounds, Z-3-HAL and E-2-HAL, as signaling inducers in Arabidopsis. Reactive cells have also been identified in plants: these cells include so-called barrier cells, mesophyll cells, and epidermal cells. Cap cells are bean-shaped cells on plant surfaces that form stomata (gas exchange openings), that is, small pores (air vacuoles) that open when plants “inhale” carbon dioxide. Mesophyll cells are the inner tissue of leaves, and epidermal cells are the outer layer of plant leaves, i.e. the “skin”. When Arabidopsis plants were exposed to Z-3-HAL, portal cells generated calcium signals within about a minute, and then mesophyll cells took over the message. Furthermore, pre-treatment of plants with a plant hormone that closes stomata significantly reduced calcium signals, suggesting that stomata actually function as the plant's “nostrils.” So, as you can see in the video below, the healthy plants received the messages from their damaged neighbors clearly and clearly and responded with calcium signals spreading through their elongated leaves.
(source: Science AlertImage: Pixabay/Kathas_Fotos)
