Abstract |
APPs (aryloxyphenoxypropionates) and CHDs (cyclohexanediones) are two of the most important groups used post-emergence for the control of grass weeds. They inhibit the lipid synthesis in plants by interfering with the activity of the enzyme Acetyl-coenzyme A carboxylase (ACCase), acting at a meristematic level. The resistance patterns of the biotypes characterized seem to indicate the existence of different degrees of resistance. It is thus possible to identify biotypes presenting cross-resistance only to certain APPs, to APPs and CHDs, or only to CHDs. The objective of this work was to evaluate the cross-resistance to fenoxaprop-P-ethyl, fluazifop-P-butyl, propaquizafop, cyhalofop-butyl, haloxyfop-R-methyl, tralkoxydim and tepraloxydim in three species of Lolium (L. multiflorum, L. perenne, and L. rigidum) resistant to diclofop-methyl. The assays were conducted with petri-dishes in which, over increasing doses, fifty seeds per biotype and dose were located in each dish. Two weeks later, the following parameters were evaluated: germination (%), number of roots, radicle length, plumule length, and fresh weight reduction (%). Based on plumule length and fresh weight reduction (%), diclofop-methyl resistant biotypes showed cross-resistance to fenoxaprop-P-ethyl, fluazifop-P-butyl, cyhalofop-butyl, haloxyfop-R-methyl, but not to propaquizafop, tralkoxydim and tepraloxydim. The parameters germination (%), number of roots or root length did not show a good relation between the dose and its efficacy (curves of dose response) for any of the susceptible and resistant biotypes studied.
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Authors | P Michitte, N Espinoza, R De Prado |
Journal | Communications in agricultural and applied biological sciences
(Commun Agric Appl Biol Sci)
Vol. 68
Issue 4 Pt A
Pg. 397-402
( 2003)
ISSN: 1379-1176 [Print] Belgium |
PMID | 15149135
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Enzyme Inhibitors
- Herbicides
- Acetyl-CoA Carboxylase
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Topics |
- Acetyl-CoA Carboxylase
(antagonists & inhibitors)
- Chile
- Dose-Response Relationship, Drug
- Enzyme Inhibitors
(pharmacology)
- Herbicides
(pharmacology)
- Immunity, Innate
- Lolium
(classification, drug effects)
- Species Specificity
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