Plants as Cold Specialists from the Ice Age
Published:27 Dec.2021 Source:Heidelberg University
‘With the challenges of increasing global warming, developing a basic understanding of how plants adapted to severe environmental change is increasingly urgent,’ stresses Prof. Koch, whose ‘Biodiversity and Plant Systematics’ working group conducts research at the Centre for Organismal Studies (COS). In many cases, their evolutionary past also strongly determines the future adaptability of plants as well as their ability to develop into new forms and types, he continues. The spoonweed genus, or Latin Cochlearia, from the Brassicaceae family separated from its Mediterranean relatives more than ten million years ago. While their direct descendants specialised in response to drought stress, the spoonweeds conquered the cold and arctic habitats at the beginning of the Ice Age 2.5 million years ago.
In controlled lab experiments, the researchers studied cultivated species from both groups to determine how they repeatedly adapted during the relatively rapidly alternating cold and warm periods over the last two million years. A ‘cold training’ indicates that the physiological adaptations to drought and salt stress during their early evolution later helped the plants develop a high tolerance to cold. Although the researchers expected that both groups would show a pronounced response to this ‘cold training,’ there appeared to be no significant difference in response to cold stress between the cold specialists of the Arctic and Alpine regions and the dry specialists or species adapted to salt water from the Mediterranean.