Weed Research (1995) 35, 149-155

P. Boutsalis and S.B. Powles (1995)
Resistance of dicot weeds to acetolactate synthase (ALS)-inhibiting herbicides in Australia
Weed Research 35 (3), 149-155
Abstract: A biotype of Sonchus oleraceus L. and two bio types of Sisymbrium orientale Torn., SSO 3 and NSO 1, are the first dicot weeds in Australia to develop resistance to ALS-inhibiting herbicides. The resistant biotypes had been exposed to va rying periods of selection with sulfonylurea her bicides. All three biotypes are resistant to a range of sulfonylurea and imidazolinone herbicides. The S. orientale biotypes are also resistant to the triazolopyrimidine herbicide, flumetsulam. LD₅₀ ratios of resistant Sonchus oleraceus for sulfony lurea and imidazolinone herbicides are greater than 64-fold and 4.5-fold, respectively. GR₅₀ ratios are greater than 9 for sulfonylureas and 7.4 for imazapyr. The LD₅₀ ratios for both S. orien tale biotypes for chlorsulfuron, sulfometuron methyl, metsulfuron-methyl, flumetsulam and imazethapyr are greater than 110-, 15-, 7-, 24- and 29-fold, respectively. All resistant biotypes are susceptible to MCPA, diuron and diflufenican, herbicides which do not inhibit ALS.
(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): Stephen B. Powles, Peter Boutsalis

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

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Sisymbrium orientale (weed)
	Sonchus oleraceus (weed)