Weed Science (2018) 66, 581-585

David J. Brunton, Peter Boutsalis, Gurjeet Gill and Christopher Preston (2018)
Resistance to multiple PRE herbicides in a field-evolved rigid ryegrass (Lolium rigidum) population
Weed Science 66 (5), 581-585
Abstract: A population of rigid ryegrass (Lolium rigidum Gaudin) from a field on the Eyre Peninsula, South Australia, was suspected of resistance to thiocarbamate herbicides. Dose–response studies were conducted on this population (EP162) and two susceptible populations (SLR4 and VLR1). The resistant population exhibited cross-resistance to triallate, prosulfocarb, EPTC, and thiobencarb with higher LD50 to triallate (14.9-fold), prosulfocarb (9.4-fold), EPTC (9.7-fold), and thiobencarb (13.6-fold) compared with the susceptible populations SLR4 and VLR1. The resistant population also displayed resistance to trifluralin, pyroxasulfone, and propyzamide. The LD₅₀ of the resistant population was higher for trifluralin (13.8-fold), pyroxasulfone (8.1-fold), and propyzamide (2.7-fold) compared with the susceptible populations. This study documents the first case of field-evolved resistance to thiocarbamate herbicides in L. rigidum.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Peter Boutsalis

Research topic(s) for pests/diseases/weeds:
pesticide resistance of pest

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Lolium rigidum (weed)		Australia (South+SE)