GE Tomatoes Show Opposite Responses to Abiotic and Biotic Stresses

Plants produce high levels of reactive oxygen species (ROS) when exposed to stressful conditions. ROS are molecules that signal and regulate plant stress responses. Thus, Stéphane Herbette from Université Blaise Pascal, France, and colleagues investigated the role of a key ROS scavenger enzyme (glutathione peroxidase or GPx) in response to biotic and abiotic stresses. They used genetically engineered (GE) tomato plants overexpressing GPx. The GE tomato and the control plants were exposed to mechanical stimulation and necrotrophic parasites Botrytis cinerea and Oidium neolycopersici.

Results showed that GPx-overexpressing plants were less sensitive to mechanical stress compared to control plants. However, GE plants exhibited increased lesion extension compared to the controls. Thus, GPx overexpression aggravated opposite effects in cases of biotic and abiotic stresses, which implies that GPx is vital in the control of stress response.

Read the research article published by the Plant Science journal at http://dx.doi.org/10.1016/j.plantsci.2010.12.002.