Have Scientists Found the Brain of a Plant?

Plants may be smarter than we thought.

Scientists at the University of Birmingham have identified a group of cells within plant embryos, specifically in the root tip, which is capable of decision-making to determine whether the plant should remain dormant or germinate. This decision-making center is similar to an analogous mechanism in human brains.

Published in the Proceedings of the National Academy of Sciences (PNAS) this week, the study shows that this small group of cells in the plant's embryo can assess environmental conditions surrounding the plant which determine whether it is a good time to germinate. The hormones that activate movement in the plant (in the case of germination) are similar to the decision-making center involved in movement in human brains.

A plant determines when to germinate based on a number of environmental factors including temperature. If the plant chooses to germinate too early in the season, it may be damaged by winter conditions; if it is too late, it might be outcompeted by stronger plants.

Specifically, scientists used mathematical modelling in the study to show that communication between the two separate cell types, one responsible for germination and the other for dormancy, is dependent on environmental conditions. They enhanced communication between the cells in a mutant plant (specifically one called Arabidopsis, or thale cress), to demonstrate that the timing of germination depends on the environment. This proved the scientists' theory that more seeds would germinate when exposed to varying environments, such as fluctuating temperatures, rather than constant environments and temperatures.

"Our work has important implications for understanding how crops and weeds grow," said study author George Bassel of the University of Birmingham. The knowledge gained in the study can be applied to commercial plants and crops to control germination, which may increase crop yields and potentially eliminate the need for herbicides.