Plants remember how much warmer than usual it was last year

Animals can adapt quickly to survive adverse environmental conditions. Evidence is mounting to show that plants can, too. A paper in the journal Trends in Plant Science details how plants are rapidly adapting to the adverse effects of climate change, and how they are passing down these adaptations to their offspring.

Plants are facing more environmental stressors than ever. For example, climate change is making winters shorter and less severe in many locations, and plants are responding. “Many plants require a minimum period of cold in order to set up their environmental clock to define their flowering time,” says Martinelli. “As cold seasons shorten, plants have adapted to require less period of cold to delay flowering. These mechanisms allow plants to avoid flowering in periods where they have less chances to reproduce.”

Animals use neurons to create memories, but plants like neurons and so need another method to remember.

Plants possess a somatic memory that can last for some time during the life of an individual plant, and is maintained through mitosis…, but there is also increasing evidence of long-lasting memories with information transmitted to one or more subsequent generations… In this context, epigenetic mechanisms have drawn attention because they can mediate the learncing, storage, and transmission of information without modification in the DNA sequences… As such, these modifications, which constitute an epigenetic alphabet, orchestrate the response of plants to their environment and are essential actors in the priming phenomenon. Epigenetic modifications are also key elements of the molecular mechanisms underlying plant memory, as well as of the ability of plants to forget, and therefore appear as an essential component of plant intelligence.

Gallusci et al. 2022.

The authors add in their paper that epigenetics also allows plants to transmit their experiences to their offspring. However this isn’t all good news, there may be a cost to balance the benefit. The team conclude: “Although the phenomenon of transgenerational stress memory protects offspring against the previously occurred stress, it is also likely that inter/transgenerational-induced resistance is associated with an increased susceptibility to other stresses.”

📰 Press Release at Eurekalert.
🔬 Read Deep inside the epigenetic memories of stressed plants at Trends in Plant Science.