Biologists have discovered a unique epigenetic memory mechanism that allows plants to determine the changing of seasons, reports infohub.kz.
Scientists at the University of Tsukuba have figured out how plants assess environmental changes and choose the ideal time to flower. It turns out they rely not on momentary temperature fluctuations but on the readings of a built-in biochemical season meter.
During a two-year study, researchers observed two wild species of the cabbage family in Japan: wasabi and Arabidopsis halleri. They tracked the activity of three key genes and compared it with temperature data from previous weeks and months. The genotype's response to climate changes occurs over three different time scales: from a few days and weeks to a record five months.
Since DNA cannot directly record environmental changes, plants store past temperatures through epigenetic modifications of chromatin. This mechanism protects them from random anomalies. A sudden winter warm spell or spring frosts do not disrupt their internal clock, allowing them to accurately predict the onset of the next season.