Will glyphosate resistance spread?
Resistance genes can potentially spread through either pollen or seed movement. The great majority of ryegrass pollen is generally only viable within 30m of the source plant. In the case of glyphosate resistance, gene transfer through pollen has not been shown to be a major factor. Weed seed can be moved between paddocks or farms by livestock, machinery, crop seed, fodder, water and wind and care needs to be taken to ensure that glyphosate resistance is not spread in this way. Many known glyphosate resistant populations in Australia have not rapidly increased in size, suggesting that resistance will not spread quickly if identified early and managed well.
