Today: Friday, 19 August 2022 year

Science: how do trees know when to awake in spring?

Science: how do trees know when to awake in spring?

Trees are smart creatures, they can calculate time and take terrible abuse like living in the extra low temperatures. Every spring the trees know exactly the right time to awake, every autumn hey knows when to fell asleep. The researchers from the Norwegian University of Life Sciences (NMBU) revealed how the tree does it and published the results in journal Science.

Trees in cooler climates need to protect their future branches when autumn comes and the chances of frost increase but weather fluctuates year to year, and seasons are often unsteady.  Over many decades, botanists have searched for the answers to the question, and the chemistry helped them in finding an answer.

The plant hormone abscisic acid (ABA) means a lot to the tree, buds do not remain dormant long enough without receiving this signal compound, the scientists revealed in the 1960s. The modern botany confessed that winter dormancy always looked mystical. Professor Torgeir Rhoden Hvidsten at the NMBU has published his article where he tells about clogging communication between the cells inside the winter bud, preventing growth cells from emerging.

“The hormone ABA initiates production of the regulator compound callose, which in turn constricts the channels between the cells in the winter bud,”

says Hvidsten.

“And these blockings require a long cold period to break up.”

The channels do not re-open until deep into spring, thus allowing the cells to again get the message to start growth. This prevents unseasonal warm periods in winter from enticing the buds to sprout. Through evolution, trees have developed a wide variety of impressive mechanisms for tackling the challenges of nature, even the manipulating genes, say the researchers from Norway.