BACKGROUND:

This study confirms and characterises glyphosate resistance in two polyploid Echinochloa colona populations from north-eastern Australia.

RESULTS:

Glyphosate dose response revealed that the two resistant populations were marginally (up to 2-fold) resistant to glyphosate. Resistant plants did not differ in non-target-site foliar uptake and translocation of 14 C-glyphosate but contained the known target-site EPSPS mutation Pro-106-Thr and/or Pro-106-Leu. Although plants carrying either a single or two EPSPS mutations were glyphosate-resistant relative to the susceptible population, they were still controlled at the field rate of glyphosate (450 g a.e. ha-1 ) when treated under warm conditions (25/20 °C). However, when treated in hot conditions (35/30 °C), most mutant resistant plants (68%) can survive the field rate, and an increase (2.5 fold) in glyphosate LD50 was found for both the R and S populations.

 

(후략)