The fact that plants do not live a passive life has been known for sometime now. In 2012, a team of researchers led by Professor Nick Smirnoff from The University of Exeter, was able to visually prove that they communicate with each other and now two totally separate research studies reveal that these silent communicators may actually be 'talking' to each other and us!
If you have ever noticed that certain plants seem to thrive next to each other, it may not be a coincidence nor proof of your superior gardening skills, but because of the good neighborly feelings between the two. At least that's what an Australian team of researchers led by Monica Gagliano, believes.
The evolutionary ecologist at the University of Western Australia asserts that plants use some kind of acoustic signaling to communicate with each other and depending on if it is good or hostile, it may allow the weaker plant to thrive or wither away. What's even more interesting is that the scientist believes the communication happens as early as the germination stage.
Monica, who published her findings in the May 7th online edition of BMC Ecology, reached this conclusion following an interesting study she conducted with some chili pepper, basil and fennel plants. She began by planting the chili seeds in isolated dishes next to fennel plants. Not many germinated. Then she conducted the same experiment next to some basil plants. Sure enough, the chili peppers not only germinated rapidly, but also, thrived.
In order to eliminate other known means of plant communications like chemical and light signals, as well as, physical contact, the scientist covered the cylindrical pot containing the seeds with black plastic and re-exposed them to the plants. The results did not change.
The led her to conclude that plants have a secret language that they use to communicate with each other. She believes that fennel is a bad neighbor that competes aggressively by releasing chemicals that stunt the growth, whilst basil produces good chemicals that keep the weeds and insects out - And thanks to the secret microscopic sounds generated within the plant cells, even the seeds of the chili pepper are made aware of that.
Though this phenomenon still needs to be researched further, Monica believes that armed with this knowledge, farmers may be able to use sound to encourage or discourage the growth of certain plants, helping to reduce their dependence on fertilizers and pesticides.
If that is not interesting enough, how about the fact that some French scientists were recently able to reproduce and actually hear the sounds trees make, when they are in a drought situation and gasping to extract as much water as they can, from the ground.
This fascinating discovery was made by Grenoble University physicist Philippe Marmottant, and two of his postgraduate students. They began their experiment by taking slivers of a dead pine tree and bathing it in hydrogel - essentially creating the conditions of a living tree.
They then exposed the branch to an artificially dry environment and recorded the sounds that emanated. What they heard were popping or gasping sounds made by the simulated tree as it tried to draw in the small quantity of water that was available. Though this happens frequently in nature, the sounds move at about 300 kilohertz or more than 10 times faster than what the human ear can hear - In this case, the scientists were able to hear it because they managed to slow down the speed substantially.
The reason for this gasping noises can be traced back to the normal water drawing cycle inside a tree. In order to absorb the carbon dioxide from the atmosphere, plants open their pores, which results in loss of water. This creates a void in the leaves, which in turn creates almost a vacuum like atmosphere in the tree trunk, causing the roots to absorb more water. However, when water is scarce, the roots draw up air bubbles, which is what make the popping sounds that the scientists describe as 'gasping' noises.
They and another team of scientists from US-based Duke University, are now in a race to develop sensors that will be able to detect these sounds which may help in saving many trees from dying. That's because while some trees like Douglas firs and Pine trees are able to repair damage caused by the air bubbles rapidly, they are deadly for others, especially if they block the water flow to the leaves.
So be sure that your garden is filled with friendly plants and if you are one of those that constantly forgets to water the houseplant, do change your habits. After all, you do not want your poor plant gasping, do you?