Key to herbicide resistance
26.03.2013 - British researchers have found that one single protein seems to control resistance against multiple herbicides of cereal crops weeds.
Multiple-herbicide resistance (MHR) in black-grass and annual rye-grass is a global threat for agriculture, leading to loss of chemical weed control in cereal crops. Until now, it was only poorly understood why MHR is associated with an enhanced ability to detoxify xenobiotics. Assuming an analogy with multiple drug resistance, which occurs in human tumours, researchers from York University and Syngenta now report they have found a possible explanation.
When they searched in black-grass and annual rye-grass for a plant homologue to the MDR causing phi glutathione S transferase (GSTP1) they found an enzyme that also showed both detoxification and signalling. When expressed in Arabidopsis thaliana, the protein termed GSTF1 led to multiple herbicide resistance in the model organism and showed a similar secondary metabolism pattern as the weeds. Those were not associated with a differential gene expression pattern but directly caused by GSTF1.
When they applied the GSTP1 blocker 4-chloro-7-nitro-benzoxadiazole to the weeds, the MHR masterswitch was blocked. They conclude that overexpression of GSTF1 orchestrates multi-herbicide resistance in grass weeds and that targeting the protein is a promising approach to regain weed control in cereal crops.