Search results for "herbicide resistance"
showing 10 items of 20 documents
Assessing the effect of changes of agricultural practices accompanying herbicide-tolerant crops on agricultural biodiversity. A simulation study with…
2014
International audience
New polymorphic markers for genetic diversity studies in an invasive plant: the common ragweed (Ambrosia artemisiifolia L.)
2014
Common ragweed is an annual herb that belongs to the Asteraceae family. It is known as an invasive plant originating from the USA. In France the common ragweed is especially abundant in the Rhône-Alpes basin and currently spreads northwards in Burgundy. Ragweed colonizes different types of environments, such as railways, river sides, wastelands, farmlands and cultivated crops (especially sunflowers crops). Herbicide resistance to linuron, glyphosate and/or acetolactate synthase inhibitors has been reported in the USA, which complicates the chemical control of ragweed. In addition, the highly allergenic pollen of ragweed causes severe allergies. These elements make this plant a major threat …
Historique de l'utilisation des herbicides en France: premières analyses
2010
A data base on the herbicides used in France since 1961 has been built up from the phytosanitary index annually edited by the Association de Coordination Technique Agricole (ACTA). This data base gives the number of active ingredients, associations and commercial products registered every year and for each crop. We also gathered the modes of action, the way of absorption sites and the species susceptibility. Since 1961, 215 molecules have been registered. The number increased regularly with a maximum of 138 in 2002 and only around 100 remain in 2010. The evolution of the number of modes of action available for weed control in wheat is discussed.
Regional study of herbicide resistance of Alopecurus myosuroides Huds. in France
2006
International audience; Since the 1990s in the north-west of Europe, the spread of herbicide resistance in wheat weeds such as Alopecurus myosuroides Huds. (blackgrass) is becoming more and more important. In the French administrative district Côte d’Or resistance to fenoxaprop within A. myosuroides populations was first detected in 1996. In 2003, 149 fields from this district were randomly sampled and about 125 A. myosuroides populations were tested for herbicide resistance. The agronomic history of all sites was investigated. Most the populations of A. myosuroides investigated contained at least 50 % of plants with resistance to fenoxaprop. In 53 and 9 % of these populations at least 50 %…
How ALS-inhibitor herbicide-resistant cultivars impact on weed resistance occurrence and management ?
2013
As soon as herbicides inhibiting the acetolactate synthase (ALS, or AHAS) were commercially released, research on herbicide-resistance genes was launched by industry and resulted before the end of the 80s in a wide diversity of resistant crop germplasms. Herbicide-resistant material was obtained by all diverse kinds of breeding techniques, but mainly mutants were used as commercial cultivars. According to the mutation place along the herbicide-binding domain corresponding DNA sequence, resistance is conferred to sulfonylureas (SU) or imidazolinones (IMI), and in some instances to both with various degrees of efficiency. These herbicides are used against a large panel of annual and perennial…
Occurrence of non-target-site-based resistance to ALS inhibitors in the broadleaf weed Papaver rhoeas (corn poppy).
2013
The vast majority of reported cases of resistance to ALS inhibitors in broadleaves is due to the selection of mutant, herbicide-resistant ALS alleles carrying a mutation at one of a few ALS codons that can be easily identified (ALS-based resistance). Non-ALS-based resistance (non-target-site resistance, NTSR), considered to be endowed by differences in the expression of many genes, has essentially been reported in grasses and hardly ever in broadleaves. We investigated NTSR to ALS inhibitors in poppy by pairing plants resistant to ALS inhibitors with susceptible plants and subsequently analysing the segregation of resistance in F1 families. Poppy plants resistant to ALS inhibitors were geno…
Characterisation of rye-grass (Lolium sp.) transcriptome-wide response to ALS-inhibiting herbicides
2014
International audience; Non-target-site-resistance (NTSR) to herbicides is a major cause for failure in the chemical control of a number of weeds, and is especially widespread and important in grass weeds. Although several gene families have been shown to be involved in NTSR (cytochromes p450, glutathione-S-transferases, glycosyl-transferases, ABC transporters, esterases…), the genetic determinants of NTSR are still poorly known to date. NTSR is part of the response of weeds to herbicides. To unravel NTSR, it is thus of interest to firstly characterise the processes involved in herbicide stress response in grasses. For this purpose, we implemented a comparative whole-transcriptome sequencin…
Conséquences de l’utilisation de variétés de tournesol tolérantes aux herbicides sur la flore des agrosystèmes
2022
The farming practices associated with the use of sunflower herbicide-tolerant varieties (HTVs) have raised concerns among public authorities, who have recommended monitoring the potential effects of HTVs on biodiversity. In this context, at the scale of three French departments, the vegetation of 239 sunflower fields and their margins was studied between 2017 and 2019. This lower weed diversity can be attributed to shorter crop rotations and higher herbicide use. Admittedly, the higher densities of A. artemisiifolia observed in plots with HTVs are the cause of the use of these varieties rather than the consequence of these practices. However, these practices do not seem to solve the problem…
Evolution of herbicide resistance in mugwort (Ambrosia artemisiifolia L.): search for genetic determinisms and application to molecular diagnosis
2022
Common ragweed (Ambrosia artemisiifolia L.), a particularly troublesome and allergenic weed, is mainly controlled in agricultural fields using ALS inhibitor herbicides. Recent cases of herbicide resistance have been reported in France and are jeopardising the efficacy of this mode of action. Both target site resistance (TSR, structural mutation in ALS gene) and non target site resistance (NTSR, regulatory and/or structural mutations in secondary metabolism) are involved. The fundamental aim of this work was to identify the genetic determinisms of resistance to ALS inhibitors that have evolved in common ragweed populations in France. As an applied objective, this work also aimed to prepare t…
Validation of a set of reference genes to study response to herbicide stress in grasses
2012
Abstract Background Non-target-site based resistance to herbicides is a major threat to the chemical control of agronomically noxious weeds. This adaptive trait is endowed by differences in the expression of a number of genes in plants that are resistant or sensitive to herbicides. Quantification of the expression of such genes requires normalising qPCR data using reference genes with stable expression in the system studied as internal standards. The aim of this study was to validate reference genes in Alopecurus myosuroides, a grass (Poaceae) weed of economic and agronomic importance with no genomic resources. Results The stability of 11 candidate reference genes was assessed in plants res…