WITH climate change poised to create havoc, plants may not be the first victims that spring to mind. But many are completely dependent on subtle aspects of the weather to survive, so changes in climate will be crucial.
Take reproduction. In order to flower at the right time, many plants must experience a period of cold to trigger a process called vernalisation. The word comes from the Latin vernus for 鈥渙f the spring鈥�. If it doesn鈥檛 get cold enough, flowering is much delayed or may not happen at all. What鈥檚 more, some of the plants that need to be vernalised are important food species such as sugar beet and wheat, which feed millions and provide much-needed income globally.
We鈥檝e known about vernalisation for quite some time. In the Stalinist era, Soviet pseudo-scientist Trofim Lysenko coined the term, and boosted his career by declaring that he鈥檇 discovered the process. He hadn鈥檛. He went on to claim, with no evidence at all, that vernalisation was an environmentally acquired characteristic that could be inherited. Eventually, his claims were demolished scientifically, but not before he had brought about the demise of genetics in the Soviet Union.
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Now, once again, people are talking about vernalisation. Last winter was Europe鈥檚 warmest for 500 years. So where does that leave plants that need to feel prolonged cold in order to flower?
Fortunately, it鈥檚 not all doom and gloom. Plant biologists such as Caroline Dean and her team at the John Innes Centre in Norwich, UK, are discovering a whole lot more about a gene called FLC, which prevents flowering over the winter: how cold turns it off and what keeps it turned off.
Apparently, individual Arabidopsis (thale cress) varieties have evolved to suit local conditions. Depending on which part of the world they live in, they need different lengths of prolonged cold to flower at the correct time. Just four weeks of solid cold is enough for Arabidopsis plants in Edinburgh, Scotland. But for a Swedish Arabidopsis, that four weeks of cold will certainly switch off the FLC gene, but the moment the temperature rises, it turns on again. The only way to turn it off until spring really arrives is an increasingly improbable 14 straight weeks of cold.
So how will plants fare in a rapidly changing climate? Dean hopes they will adapt, and thinks that they might be able to do so in less than a millennium. Indeed other genes that control flowering, such as FRIGIDA, show signs of having evolved over 400 to 800 years. While this is a short hop in evolutionary time, it could be a bit too long for us humans facing climate change.
Plant biologists don鈥檛 want to leave things to chance. Dean and her colleagues plan to collaborate with climate scientists at the nearby University of East Anglia and use their findings to tailor plants to survive every kind of winter, from short but cold with mild snaps, to long and warm.
鈥淧lant biologists don鈥檛 want to leave things to chance鈥�
Just don鈥檛 ask them what they鈥檒l do if winter dwindles to just one coolish day in February.
