Plants have memory

Researchers have found that plant cells can memorise environmental stress to prepare themselves for subsequent onslaughts.

Climate Change and Environment

Plants have no nervous system, but they are able to monitor, memorise and anticipate environmental changes on a cellular level. With the effects of global warming in mind, it is important to understand how plants react and adapt to environmental stress. The PLANT-MEMORY (Role of Pc-G and Trx-G genes in the cellular memory of extrinsic signals in plants) project studied how plants react to ultraviolet (UV) radiation, disease and drug stress, and how they retain that information. Two of the main mechanisms of cellular memory are the genetic make-up and epigenetic modification of chromatin. Epigenetic mechanisms are induced by the environment to cause changes in the chromosome structure without altering the DNA. Epigenetic changes are copied during cell development and replication, which ultimately helps the plant retain a 'memory' of its reaction to an environmental event. The PLANT-MEMORY study found that plants have an acquired resistance to diseases and drugs after their first exposure to the stress. Upon second exposure to stress, researchers measured a quicker and more effective plant response compared to the previous stress challenge. Even if the original infection was localised, the plants could acquire systemic immunity to distance infection away from the original infected site. The project identified several genes that are primed to react to UV radiation. The study also identified the role of different epigenetic marks in response to disease and drugs. PLANT-MEMORY gave rise to several spin-off projects, the results of which will have a direct impact on agriculture, health and sustainable development.