With Climate Change Comes Weeds

Researchers at the U.S. Department of Agriculture's Agricultural Research Service (USDA ARS) are studying how global climate change could affect crop production and possibly prompt the evolution of more resilient weeds. Specifically, the scientists are looking as to how rising temperatures and rising carbon dioxide (CO2) levels could change production dynamics and crop yields.

Lewis Ziska and colleagues found that the growth of the genetically modified, glyphosate-resistant soybeans is promoted by high CO2 levels. Elevated CO2 levels also stimulate the growth of weeds that are typically kept in check by the herbicide glyphosate. Corn plant growth, on the other hand, was found to be suppressed by warmer temperatures resulting from high CO2 levels. Other work by the scientists shows that cheatgrass and Canada thistle--which are both aggressive and invasive weeds, flourish when CO2 levels rise, and that some varieties of dandelions have the genetic ability to adapt rapidly to rising CO2 levels. The researchers concluded that the variability in dandelions and other weeds might provide genetic material that could be used to breed high-yielding, climate proof plants.

 Read the original story at http://www.ars.usda.gov/IS/pr/2009/091110.htm