A decade of monitoring herbicide resistance in Lolium rigidum in Australia
J. C. Broster A B and J. E. Pratley AA E. H. Graham Centre for Agricultural Innovation (Charles Sturt University and NSW Department of Primary Industries), Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
B Corresponding author. Email: jbroster@csu.edu.au
Australian Journal of Experimental Agriculture 46(9) 1151-1160 https://doi.org/10.1071/EA04254
Submitted: 24 November 2004 Accepted: 21 December 2005 Published: 4 August 2006
Abstract
Charles Sturt University commenced herbicide resistance monitoring in 1991. A random survey in 1991 to determine the level of resistance in annual ryegrass (Lolium rigidum) to selective herbicides across the south-west slopes region of New South Wales found that 30% of samples were resistant to at least 1 herbicide. A subsequent survey of commercially available ryegrass seed found that 58% of these samples were resistant to at least 1 herbicide. As a result of these findings, a commercial testing service was established and has since received samples from a large proportion of the southern Australian cropping belt. Seventy-seven percent of samples tested were resistant to Group AI, 40% to Group B and 22% to Group AII herbicides. Lower levels of resistance were found to Group D (8%), Group C (1%) and Group M (0.4%) herbicides. The correlation between resistance in Group AI and AII herbicides was lower than expected given that these herbicides are considered to have the same mode of action. Within the Group AI herbicides the observed response of the samples was consistent across herbicide formulations. Resistance to clethodim varied from observed responses to other Group AII herbicides. The variation in resistance levels (and degree of multiple resistance) in each Australian state is discussed in relation to environmental conditions and cultural practices. The size of this dataset allows for the analysis of the relationships present among herbicide resistant annual ryegrass.
Additional keywords: annual ryegrass, clethodim, cross-resistance, mode of action, multiple resistance.
Acknowledgments
The authors acknowledge the contributions from the following people in aspects of the work presented in this paper: P. Baines, R. Graham, A. Leys, J. Ingrey. The following herbicide companies contributed chemicals to support the testing service: Bayer CropScience, BASF Australia, CropCare Australasia, Dow AgroSciences, DuPont, Monsanto, Nufarm, Sumitomo Chemicals and Syngenta Crop Protection. Dow AgroSciences managed the WeedSense program.
Black ID,
Pederson RN,
Flynn A,
Moerkerk M,
Dyson CB,
Kookana R, Wilhelm N
(1999) Mobility and persistence of three sulfonylurea herbicides in alkaline cropping soils of south-eastern Australia. Australian Journal of Experimental Agriculture 39, 465–472.
| Crossref | GoogleScholarGoogle Scholar |
(verified 20 June 2006)
Heap J, Knight R
(1982) A population of ryegrass tolerant to the herbicide diclofop-methyl. Journal of the Australian Institute of Agricultural Science 48, 156–157.
Heap I, Knight R
(1986) The occurrence of herbicide cross-resistance in a population of annual ryegrass, Lolium rigidum, resistant to diclofop-methyl. Australian Journal of Agricultural Research 37, 149–156.
| Crossref | GoogleScholarGoogle Scholar |
Llewellyn RS, Powles SB
(2001) High levels of herbicide resistance in rigid ryegrass (Lolium rigidum) in the wheat belt of Western Australia. Weed Technology 15, 242–248.
| Crossref |
Powles SB,
Preston C,
Bryan IB, Jutsum AR
(1997) Herbicide resistance: impact and management. Advances in Agronomy 58, 57–93.
Powles SB,
Lorraine-Colwill DF,
Dellow JJ, Preston C
(1998) Evolved resistance to glyphosate in rigid ryegrass (Lolium rigidum) in Australia. Weed Science 46, 604–607.
Pratley J,
Urwin N,
Stanton R,
Baines P,
Broster J,
Cullis K,
Schafer D,
Bohn J, Kruger R
(1999b) Resistance to glyphosate in Lolium rigidum. I. Bioevaluation. Weed Science 47, 405–411.