Detection of the I1781L mutation in fenoxaprop-p-ethyl-resistant American sloughgrass (Beckmannia syzigachne Steud.), based on the loop-mediated isothermal amplification method

BACKGROUND: The increasing use of fenoxaprop-p-ethyl has resulted in evolved resistance in American sloughgrass (Beckmannia syzigachne Steud.). Target-site-based resistance to acetyl-CoA carboxylase (ACCase) inhibitors in B. syzigachne occurs owing to an isoleucine-to-leucine substitution at residue 1781 (I1781L) of the ACCase enzyme. A rapid detection method is needed to identify the resistance-conferring substitution. RESULTS: Four populations of B. syzigachne that were resistant to fenoxaprop-p-ethyl and contained the I1781L substitution were identified. Conventional PCR and derived cleaved amplified polymorphic sequence (dCAPS) methods were used to detect the mutation. Additionally, a rapid nucleic acid detection method, loop-mediated isothermal amplification (LAMP), was successfully developed and used to detect the genetic mutation underlying the I1781L substitution in the B. syzigachne ACCase enzyme. CONCLUSION: This report is the first to describe the application of a LAMP assay for mutation detection in herbicide-resistant weeds. The assay does not require specialised equipment: only a standard laboratory bath is needed. This technique could be employed for detecting the I1781L substitution in B. syzigachne plants and seeds. (C) 2014 Society of Chemical Industry