[{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/6469\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003EPlants can override their body clocks when stressed\u003C\/h2\u003E\u003Cp\u003EMost organisms have the innate ability to measure time and, when we think they are reacting to sunrise or sunset, they are in fact ahead of the game, with an internal clock that allows them to anticipate the changes ahead. These so-called circadian rhythms are in control of many of an organisms\u2019 genes, switching them on and off as they control their daily activities.\u003C\/p\u003E\u003Cp\u003EHowever, scientists studying the wild tobacco plant (\u003Cem\u003ENicotiana attenuata\u003C\/em\u003E) have witnessed it departing from its circadian schedule in all sorts of ways to fight problems such as predators or food scarcity.\u003C\/p\u003E\u003Cp\u003EThe discovery could overturn our understanding of the role of plants\u2019 circadian clocks in controlling and orchestrating their behaviour, according to Professor Ian Baldwin, of the Max Planck Institute for Chemical Ecology in Jena, Germany, who says that the findings are raising the question of whether circadian clocks really control the plant \u2013 or whether it is the other way round.\u003C\/p\u003E\u003Cp\u003EHis team has been watching the nightly rhythms of tobacco plant flowers, which open after dusk to waft a perfume that lures the hawkmoth \u003Cem\u003EManduca sexta\u003C\/em\u003E, their pollinator of choice because of the variety of pollen it carries. The flowers also tilt themselves so that the hawkmoth\u2019s long proboscis can enter more easily.\u003C\/p\u003E\u003Cp\u003EBut the hawkmoth is an uncomfortable guest, because it lingers on the tobacco plant\u2019s leaves, laying eggs that hatch into voracious caterpillars.\u003C\/p\u003E\u003Cp\u003EIn retaliation, as soon as the caterpillars start munching its leaves, the tobacco plant sends out a vapour distress signal to the caterpillars\u2019 predators to come over for a feast.\u003C\/p\u003E\u003Cp\u003EBut this isn\u2019t always enough to halt the stripping of its foliage. So, what Prof. Baldwin\u2019s team found was that the plant can invoke a final defence. It sprouts new flowers that stay shut at night and do not tilt upwards. They open, instead, during the day to woo a different pollinator: hawkmoths vanish from the scene and the hummingbird visits instead.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EHijacked\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EProf. Baldwin says that the change in chemistry unleashed by the caterpillars \u2013 known as the jasmonate signalling cascade \u003Cspan\u003E\u2013\u003C\/span\u003E\u0026nbsp;has actually hijacked tobacco\u2019s circadian flower clock preventing it from orchestrating the normal flower behaviour.\u003C\/p\u003E\u003Cp\u003E\u2018This is clearly what\u2019s happening. I was totally amazed when we pieced it all together,\u2019 he said. \u2018Plants are not just growth machines \u2026 We see a much more environment-sensing, plastic organism.\u2019\u003C\/p\u003E\u003Cp\u003EProf. Baldwin\u2019s project, known as ClockworkGreen, is funded by the EU\u2019s European Research Council. His team tries to understand the mesh of genetic interactions that underpin circadian control by disabling individual genes to see what happens to the resulting plant.\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003E\u2018Plants are not just growth machines \u2026 We see a much more environment-sensing, plastic organism.\u2019\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EProfessor Ian Baldwin, Max Planck Institute for Chemical Ecology, Germany\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003EOne such knockout, when planted in the laboratory greenhouse, grew \u2018like rubber\u2019 across the earth instead of upright, he said.\u003C\/p\u003E\u003Cp\u003EThis was because it lacked the gene to produce its own phenols \u2013 the final stage of a long process, controlled by the circadian clock, to make lignin, which gives plants rigidity.\u003C\/p\u003E\u003Cp\u003EThe scientists were therefore astonished to find that, when they planted the same knockout seedlings in their natural habitat, they grew tall as if nothing had happened.\u003C\/p\u003E\u003Cp\u003EAt first, they assumed that their work had failed. But the truth was more interesting: the plants, undaunted by the failure to deliver phenols, had set about finding them from other sources. They harvested them from chemical pathways triggered by the secretions of predator insects, by ultraviolet light exposure, and even by wind stress. They produced a lignin that was a bit different from normal but the end result was clearly satisfactory: the plants grew tall and survived seven storms in the field.\u003C\/p\u003E\u003Cp\u003EProf. Baldwin says that the case of the rubbery plants illustrates how important it is to study how plants respond in the rough and tumble of the wild, rather than in a greenhouse where there is no rich interplay with insects, the weather and other plants.\u003C\/p\u003E\u003Cp\u003E\u2018Our basic philosophy is that if you want to understand gene function you have to understand it in the situation in which it evolved,\u2019 he said.\u003C\/p\u003E\u003Cp\u003EThis kind of work is uncommon, partly because of the time it takes. Plants have to be harvested at all times of day and night for chemical snapshots of their gene activity.\u003C\/p\u003E\u003Cp\u003EProf. Baldwin believes that the work will overturn our understanding of the function of circadian rhythms in plants when a series of papers reporting the results of the ClockworkGreen project are published later this year. \u2018We\u2019re ready for a paradigm shift,\u2019 he said.\u003C\/p\u003E\u003Cp\u003EThe research will help them learn how plants could be adapted to cope with changes in the environment.\u003C\/p\u003E\u003Cp\u003EPoplar trees also seem to be doing something clever with their body clocks, which Dr Mariano Perales, researcher at the Centre for Plant Biotechnology and Genomics just outside Madrid in Spain, is investigating.\u003C\/p\u003E\u003Cp\u003EMuch plant circadian research has been done on the molecular biologists\u2019 favourite weed, \u003Cem\u003EArabidopsis thaliana\u003C\/em\u003E, otherwise known as thale cress, which is easy to study because of its short lifecycle. But Dr Perales finds the poplar tree more interesting because it lives longer than a year and must thus synchronise itself with the seasons, not just the days.\u003C\/p\u003E\u003Cp\u003E\u2018A herbaceous plant doesn\u2019t care about the seasons,\u2019 said Dr Perales, whose project, WinClock, is funded under the EU\u2019s Marie Sk\u0142odowska-Curie programme.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EElaborate preparations\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EDr Perales, with his colleague Prof. Isobel Allona, is looking into the elaborate preparations the tree makes for the onset of winter.\u003C\/p\u003E\u003Cp\u003EIt grows layers, like an onion, to cover the growing tips of its roots and shoots. And it pumps antifreeze chemicals around to protect it from frost. And after this it enters a dormant state.\u003C\/p\u003E\u003Cp\u003EDr Perales is investigating the crosstalk between the tree and its environment that triggers this shutdown, which starts even before winter begins. It turns out there\u2019s a tapestry of chemical interactions going on, but what intrigues Dr Perales most is the fact that the clock\u2019s final act, once the poplar is ready for the cold season, is to switch itself off.\u003C\/p\u003E\u003Cp\u003E\u2018There are no circadian rhythms throughout the winter season,\u2019 said Dr Perales, who is also keen to find out what switches the clock back on again in anticipation of spring.\u003C\/p\u003E\u003Cp\u003EIf he can crack the secrets of the clock, he hopes it may be possible to breed enlightened poplar trees that do not shut down for winter. These might do well in the warmer winters promised by climate change, continuing to grow and thus being more productive.\u003C\/p\u003E\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-fxs3g32d-1gawsk5btqrqpy9qtk6xj7gjtfgfz8ktye\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-fXS3g32D-1GAwsk5btqRqPY9Qtk6xj7GJTFGFZ8kTyE\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]