Weed Research (1993) 33, 409-413

E. Purba, C. Preston and S.B. Powles (1993)
Paraquat resistance in a biotype of Vulpia bromoides (L.) S. F. Gray
Weed Research 33 (5), 409-413
Abstract: A biotype of Vulpia bromoides from a lucerne field in Elmhurst, Victoria, Australia was shown to be resistant to paraquat in pot trials. Application of paraquat at 50 g a.i. ha⁻¹ killed all of the plants of a susceptible Vulpia bromoides biotype but only 6% of the resistant biotype. The LD₅₀ for paraquat of the resistant biotype was five- to sixfold higher than for the susceptible biotype. The resistant biotype was also resistant to the bipyridyl herbicide diquat, but was susceptible to glyphosate and metribuzin. Application of 100 g a.i. ha⁻¹ paraquat at anthesis completely suppressed seed set of the susceptible biotype and reduced that of the resistant biotype by 95%. Seed set by the paraquat-treated resistant biotype, however, showed little reduction in germination. This is the fourth species to have been found to be resistant to bipyridyl herbicides in this field, the others being Hordeum glaucum, H. leporinum and Arctotheca calendula.
(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, Christopher Preston

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.
	Vulpia bromoides (weed)	Alfalfa/lucerne (Medicago sativa)	Australia (South+SE)