Variation in Elymus repens susceptibility to glyphosate

• Continuous increase in glyphosate use in Sweden has caused concern about resistance development, not least inconnection with the possible introduction of crops resistant to glyphosate. In Sweden, the main weed targetedby glyphosate is Elymus repens (L.) Gould. We sampled 69 clones of E. repens to assess the magnitude andgeographical distribution of variation in susceptibility to glyphosate. Clones originated from four habitat types:intensively and extensively used arable lands, field vicinities and other habitats, including natural vegetation.Susceptibility varied greatly among clones with GR50 (50% of untreated growth reduction) spanning over atleast one order of magnitude, 17–278 active ingredient ha−1 in a pot experiment setting. There was a strongcovariance between geographic and genetic distance, but there was no evidence of geographic or geneticdifferentiation in GR50. Nor did GR50 vary consistently between habitat types. We conclude that no indicationof past selection was found towards the resistance to glyphosate in E. repens clones in Sweden. The greatvariability in susceptibility suggests that there might be a potential for such selection.

Subject headings

LANTBRUKSVETENSKAPER  -- Lantbruksvetenskap, skogsbruk och fiske -- Jordbruksvetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Agriculture, Forestry and Fisheries -- Agricultural Science (hsv//eng)

Keyword

Agropyron repens (L.) P. Beauv.; Elytrigia repens (L.) Desv.; herbicide tolerance; herbicide resistance; Sweden

Publication and Content Type

ref (subject category)

art (subject category)