Plants are alive and have taken over most of the world.
Whether or not they consciously do it is another question, but by studying plants we can raise them to give greater crop yields, do forensic work, or learn more about the human nervous system.
The human eye can sense light, and so can plants. Light is an infinite source of energy and plants have developed delicate ways to harness that energy. The fact that animals and plants share a lot of similar characteristics has led to the emergence of a field called plant neurobiology – a field that stirs up some controversy among plant researchers.
“Plants don’t have eyes, but they do have photoreceptors. They can sense the type of light, whether it’s red, blue, or UV,” said Dr. Anireddy Reddy, who studies plants and pioneered the research of the role of calcium in plant cell signalling at CSU.
When the public starts talking about plant neurobiology though, it is a bit of a misnomer according to Dr. Marinus Pilon, who studies photosynthesis and teaches cell biology at CSU.
Pilon explains that plants and animals are actually very close on the evolutionary scale so there are definitely similarities in their physiology.
“A lot of the fundamental biochemistry is the same between plants and animals,” Pilon said.
According to Pilon, studying how plants respond to certain stimuli can tell us a lot about how organisms in general respond to their environments, but that we do not even have a really good understanding of how human consciousness works which makes it hard to see the comparison in plants.
“I think we want to be anthropomorphic in our understanding. I think it’s just the way we like to put things in models,” Pilon said.
The comparison that is most easily confused with human-like physiology is the excitability of plant cells — their ability to talk to one another is essentially how human nerve cells, called neurons, work.
Reddy is quick to add that plants do not have neurons, or cells like neurons. Plants mostly modify behavior by changing gene expression – a biochemical process that is common to all organisms.
As far as functional applications go, Dr. June Medford, biologist at CSU, said she takes over the plant’s signalling pathway.
A signalling pathway is how sensory receptors communicate the outside world the rest of the organism — much like how the human eye communicates with the brain. Medford re-designs these pathways so that they activate when they come in contact with certain pollutants. In this case, the plants respond by turning white.
“Understanding the pathway is critical to producing the effect. This plant color change is much quicker than ordinary lab testing,” Medford said.
Plants have great sensing ability because they cannot run or hide from predators, according to Medford. She said that a plant’s sensory pathways are even more sensitive than those in humans.
“They need very sophisticated senses to respond,” Medford said. “Plants can sense a very small amount of light, they can sense the type of light, the direction it’s coming from, the amount, the day length. They can sense that bugs chewed on their neighbors. They can sense wind and gravity,” Medford said.
For gardeners, there might be some basis behind the nurturing feeling felt with plants. While they do not have brains and therefore are not conscious, Reddy points out that plants are very sensitive to their environments, and some interaction can definitely influence plant growth.
“You can change the way a plant grows simply by touching it,” Reddy said.
According to Pilon, this is reason enough to study plants.
“To say that we’re going to learn about the human nervous system, I personally think it’s unlikely, but you never know right? Things like protein translation, they first were studied in plants. Think of genetics — mendel did the first experiments on peas,” Pilon said.
Collegian Science Beat Reporter Remi Boudreau can be reached at firstname.lastname@example.org.