Occurence of target site resistance to glyphosate in goosegrass (Eleusine indica (L.) Gaertn.) in Saitama prefecture, Japan

Abstract

Goosegrass (Eleusine indica (L.) Gaertn.) plants suspected to be resistant to glyphosate were collected at four locations in Saitama prefecture, Japan. Application of 132 g a.i./10 a glyphosate potassium had little effect on viability, suggesting resistant to glyphosate. On the other hand, diquat-paraquat, fluazifop and glufosinate were effective against these goosegrasses. This suggests that mechanism of resistance is likely specific to glyphosate. One of the isolates had glyphosate-resistant mutations (T102I, P106S) in the amino acid sequences of EPSPS, the target protein of glyphosate. This is the first report of target site glyphosate-resistance of goosegrass in Japan. In addition, comparison of EPSPS DNA sequences revealed glyphosate-resistant goosegrass likely occurred independently in multiple regions.