Using radioactive carbon and genetically modified native tobacco plants (Nicotiana attenuata), scientists at Max Planck Institutes in Jena and Golm (Potsdam) and at the Research Centre in Jülich have discovered the first gene mediating tolerance to herbivore attack: GAL83, the beta-subunit of Nicotiana attenuataTMs SNF-1 related kinase. This gene mediates a rapid herbivore-elicited carbon-hoarding behaviour in which recently assimilated carbon (measured with 11CO2) is squirrelled away to the roots rather than transported to young expanding leaves, to be used later to extend the period of seed and flower production when the plant is done growing. As soon as the plants are attacked by the larvae of the nicotine-resistant tobacco hornworm, Manduca sexta, elicitors from this herbivoreTMs mouth (called FACs - fatty acid conjugates), which also tune the plantTMs induced defence responses, are shown in this study to activate carbon storage in the roots. By reconfiguring where it stores carbon, the plant gains a measure of tolerance and thereby the ability to withstand voracious herbivores.

Ecological studies conducted in the department of Prof. Ian T. Baldwin at the Max Planck Institute for Chemical Ecology in Jena, Germany, focus on the defense of plants against attack from herbivores. Plants respond to attack by producing an arsenal of direct (toxins, digestibility reducers, etc.) and indirect defences that reduce the attackers' performance, thereby lessening the amount of damage inflicted to the plant. However, the co-evolutionary dynamics of the interaction often leads to herbivores that are adapted to the plantTMs defences. Resolution of this evolutionary impasse may require the kind of solution advocated by Mahatma Gandhi: tolerate the damage. Or
'"/>

Contact: Dr. Ian T. Baldwin
baldwin@ice.mpg.de
49-364-157-1101
Max-Planck-Gesellschaft
5-Sep-2006