Visiehuno Rosa
Assistant Professor, Department of Botany, St. Joseph’s College Jakhama
Humans have, for a long time, considered plants to be silent and emotionless beings, which show no signs of intelligence and motility. Most of us only know plants as autotrophs or producers which can manufacture their own food through photosynthesis, and upon which all other organisms depend on for their food. They are perceived as the group of living organisms whose purpose is to feed the other living forms on earth.
However, there are many scientists/ researchers who feel that the plants around us are not just the docile plants we know them as. Our perception about plants do changes as many of the works by these people over the years, some works though scientifically not proven or explained, show that plants have emotions, can communicate with one another and also can help each other out in times of need. These findings are now leading to the concept of plants having certain rights, just like animals and humans are entitled to their own rights such as animal rights and human rights.
Humans and animals acquire rights due to being aware. The concept of plants capable of feeling emotions, along with plant intelligence, can be traced to 1848, when Gustav Theodor Fechner, a German experimental psychologist, suggested that plants are capable of emotions, and that one could promote healthy growth with talk, attention, and affection. Plant perception or biocommunication is the paranormal idea that plants are sentient, that they respond to humans in a manner that amounts to ESP (extra sensory perception), and that they experience pain and fear.
Cleve Backster, an interrogation specialist for the Central Intelligence Agency (CIA),was best known for his experiments with plants using a polygraph instrument in the 1960s which led to his theory of "primary perception" where he claimed that plants "feel pain" and have extrasensory perception (ESP), which was widely reported in the media but was rejected by the scientific community. Backster's study of plants began in the 1960s, and he reported observing that a polygraph instrument attached to a plant leaf registered a change in electrical resistance when the plant was harmed or even threatened with harm. His work was inspired by the research of Physicist Jagadish Chandra, who claimed to have discovered that playing certain kinds of music in the area where plants grew caused them to grow faster. Jagadish used a crescograph to measure plant response to various stimuli and demonstrated feeling in plants. From the analysis of the variation of the cell membrane potential of plants under different circumstances, he hypothesized that plants can "feel pain, understand affection etc." and wrote two books about it in 1902 and 1926.
In February 1966, Backster attached polygraph electrodes to a Dracaena cane plant (a common indoor plant), to measure at first the time taken for water to reach the leaves. The electrodes are used to measure galvanic skin response and the plant showed readings which resembled that of a human. This made Backster try different scenarios, and the readings went off the chart when he pictured burning the leaf, because according to him, the plant registered a stress response to his thoughts of harming it. He conducted another similar experiment where he observed a plant's response to the death of a brine shrimp in another room; his results convinced him that plants demonstrated telepathic awareness. He argued that plants perceived human intentions, and as he began to investigate further, he also reported finding that other human thoughts and emotions caused reactions in plants, which could be recorded by a polygraph instrument. He termed the plants' sensitivity to thoughts "Primary Perception", and published his findings from the experiments in the International Journal of Parapsychology in 1968.
Recent studies carried out at Universiti Teknologi MARA, Malaysia in 2014 on the effects of various rhythms on in vitro seed germination of several orchid species showed that plants definitely showed some effects when exposed to the music. The findings from this research showed that sound play its own role in influencing plant growth by better development and even positive genetic characters. The music gave positive influence on exposed plant as compared to the non-exposed. The types of music genre used like Instrumental group, Ballad group, Yasin group, Hip-hop and Rock group also has different effects on different species as it was found that different plant species required different rhythm for their germination and best growth.
Another evidence shows that plants detect emotions is in their usage as medicine. Though not scientifically proven, it has been shown that plants give better results as medicines when the person collecting the plant material, before collecting the leaves, flowers, roots etc. from the plant, utters words of gratitude and the good intentions for which the plant is to be used for to the plant. This is a common practice observed in many of the traditional healers or people who practice ayurveda.
The 19th century German Biologist Albert Bernard Frank coined the word "mycorrhiza" to describe the partnerships between plants and fungi, in which the fungus colonises the roots of the plant. It is now known that around 90% of land plants are in this mutually-beneficial relationship with fungi. In mycorrhizal associations, plants provide fungi with food in the form of carbohydrates. In exchange, the fungi help the plants take up water, and provide nutrients like phosphorus and nitrogen, via their mycelia, which are a mass of thin delicate thread-like structures. Since the 1960s, it has been clear that mycorrhizae help individual plants to grow. The mycorrhizal association between the plant roots and the fungus underground is known to boost the host plants' immune systems. That's because, when a fungus colonises the roots of a plant, it triggers the production of defense-related chemicals. These make later immune system responses quicker and more efficient, a phenomenon called "priming". Simply connecting with the mycelial network makes plants more resistant to disease.
Paul Edward Stamets, an American mycologist called the mycelium of fungi as the "Earth's natural internet". He first had the idea in the 1970s when he was studying fungi using an electron microscope. According to him the mycelium acts as an information highway to which the roots of plants are hooked up to. The mycelium not just help individual plants in acquiring nutrients and grow, but also acts as a kind of underground internet, linking the roots of different plants. They speed up interactions between a large, diverse population of plants and allow individual plants who may be widely separated to communicate and help each other out.
So what are the benefits of hooking up to a fungal network? It has taken decades to piece together what the fungal internet can do. Back in 1997, Suzanne Simard of the University of British Columbia in Vancouver found one of the first pieces of evidence. She showed that Douglas fir tree and paper birch trees can transfer carbon between them via mycelia. Others have since shown that plants can exchange nitrogen and phosphorus as well, by the same route. Simard believes that large trees help out small, younger ones using the fungal internet. Without this help, she thinks many seedlings wouldn't survive. In the 1997 study, seedlings in the shade – which are likely to be short of food - got more carbon from donor trees.
"These plants are not really individuals in the sense that Darwin thought they were individuals competing for survival of the fittest," says Simard in the 2011 documentary Do Trees Communicate?, “in fact they are interacting with each other, trying to help each other survive."
In 2010, Ren Sen Zeng of South China Agricultural University in Guangzhou found that when plants are attacked by harmful microorganism, they release chemical signals into the mycelia that warn their neighbours. The surrounding plants thus gets a pre-disease warning signal and prepares themselves well in advance.
All these findings give us a new perspective on the very complex and diverse life forms found on earth. It also makes us re-think our perception on what intelligence is and not to consider any species less intelligent than us.
