Multiple resistance across glufosinate, glyphosate, paraquat and ACCase-inhibiting herbicides in anEleusine indicapopulation

Summary An Eleusine indica population was previously reported as the first global case of field‐evolved glufosinate resistance. This study re‐examines glufosinate resistance and investigates multiple resistance to other herbicides in the population. Dose–response experiments with glufosinate showed that the resistant population is 5‐fold and 14‐fold resistant relative to the susceptible population, based on GR 50 and LD 50 R / S ratio respectively. The selected glufosinate‐resistant subpopulation also displayed a high‐level resistance to glyphosate, with the respective GR 50 and LD 50 R / S ratios being 12‐ and 144‐fold. In addition, the subpopulation also displayed a level of resistance to paraquat and ACC ase‐inhibiting herbicides fluazifop‐ P ‐butyl, haloxyfop‐ P ‐methyl and butroxydim. ACC ase gene sequencing revealed that the T rp‐2027‐ C ys mutation is likely responsible for resistance to the ACC ase inhibitors examined. Here, we confirm glufosinate resistance and importantly, we find very high‐level glyphosate resistance, as well as resistance to paraquat and ACC ase‐inhibiting herbicides. This is the first confirmed report of a weed species that evolved multiple resistance across all the three non‐selective global herbicides, glufosinate, glyphosate and paraquat.