![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]()
Zurich, Switzerland (SPX) Feb 01, 2011 Plants are attacked by a multitude of insects and mammals. As defense against these herbivores they developed complex defense mechanisms over the course of evolution: spines, thorns, leaf hairs and a number of toxic chemical substances. For decades it has been controversially discussed whether the production of defense traits incurs costs to the plants. Now, using a new method the ecologists and plant biologists of the University of Zurich together with their American colleagues demonstrate these costs accurately in a Proceedings of the Royal Society article. For their study, the researchers planted different "knockout"-mutants of the same genotype of the model plant Arabidopsis thaliana. They then harvested a subset of these plants in evenly distributed intervals to measure the biomass growth over the whole plant life. "Mutants with suppressed defense mechanisms showed an increased growth rate" Tobias Zust explains the result of his study. But the faster growth comes at an added cost: aphids reproduce faster on these plants than on slow growing plants with intact defense mechanisms. This is a result of the fact that fast growing plants provide more resources to the herbivore than slow growing plants in the same amount of time. The study shows that natural resistance is often not compatible with fast growth. This finding is of great importance for agricultural crops: These crops have been selected for high yield and as a consequence have very low natural resistance to herbivores, consequentially requiring high input of insecticides.
Share This Article With Planet Earth
Related Links University of Zurich Darwin Today At TerraDaily.com
![]() ![]() Moffett Field CA (SPX) Feb 01, 2011 About 450 million years ago, Earth suffered the second-largest mass extinction in its history - -the Late Ordovician mass extinction, during which more than 75 percent of marine species died. Exactly what caused this tremendous loss in biodiversity remains a mystery, but now a team led by researchers at the California Institute of Technology (Caltech) has discovered new details supporting ... read more |
![]() |
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2010 - SpaceDaily. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement |