Although plants do not feel hunger or pain like animals, they are able to use signals that are linked with animals when they are under stress.
For the new study published in the journal Nature Communications on July 29, researchers reported how despite lacking a nervous system, plants react to their environment with a combination of electrical and chemical responses that is comparable to those of animals albeit the machinery is for the plants.
Study researcher Matthew Gilliham, from the University of Adelaide's School of Agriculture, Food and Wine, said that researchers have long been aware that plants produce the animal neurotransmitter known as GABA (gamma-aminobutyric acid) when they are under stress such as when they encounter viruses, salinity, drought, extreme temperatures or acidic soils but it was not known whether this neurotransmitter was used plants as signals.
"We've discovered that plants bind GABA in a similar way to animals, resulting in electrical signals that ultimately regulate plant growth when a plant is exposed to a stressful environment," Gilliham said.
Gilliham said that their findings revealed that plants bind the neurotransmitter in ways comparable to those in animals. The compound is the same among animals and plants but the proteins binding it differ, which means that animals and plants evolved how they use the compound.
"We propose that GABA exerts its multiple physiological effects in plants via ALMT, including the regulation of pollen tube and root growth, and that GABA can finally be considered a legitimate signalling molecule in both the plant and animal kingdoms," the researchers wrote.
The researchers are optimistic that they would be able to come up with new ways to modify how plants respond to stress after determining how plants respond to GABA. Knowing how the plants utilize GABA as a stress signal, for instance, could give scientists a new tool that could help in breeding crops that are more resilient to stress and this could have crucial impact on food security.
The findings may also provide insights on how plants have evolved to become what they are today. The researchers' theory is that the plant cells took the GABA neurotransmitter and co-opted it for use as a communication tool.
Researchers likewise said that the study could help explain why certain plant-derived drugs that are used as anti-epileptics and sedatives work in humans raising the possibility that studies on other plant GABA signaling agents may have useful applications in the medical industry.
Photo: Mark Dixon | Flickr