Response of Selected Horseweed (<i>Conyza canadensis</i> (L.) Cronq.) Populations to Glyphosate

Main, Christopher L.; Mueller, Thomas C.; Hayes, Robert M.; Wilkerson, J. B.

doi:10.1021/jf0351927

Cited by 67 publications

(67 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This is the case with the many biotypes of glyphosate-resistant horseweed as well as several other glyphosate-resistant weedy plant species, such as johnsongrass (Sorghum halepense), ryegrass (Lolium spp. ), velvet bean (Mucuna pruriens), and wild radish (Raphanus raphanistrum; Mueller et al, 2003;Feng et al, 2004;Main et al, 2004;Zelaya et al, 2004;Koger and Reddy, 2005;Owen and Zelaya 2005;Preston and Wakelin, 2008;Ge et al, 2010Ge et al, , 2012Riar et al, 2011;Rojano-Delgado et al, 2012;Vila-Aiub et al, 2012;Ashworth et al, 2014;Sammons and Gaines, 2014). Physiologically, we know that non-target-site resistance can involve a plethora of metabolic, conversion, sequestration, and reduced translocation processes, including oxidation, conjugation, or compartmentation of the herbicide molecules (Yuan et al, 2007;Cummins et al, 2013;Iwakami et al, 2014).…”

Section: Discussionmentioning

confidence: 99%

De Novo Genome Assembly of the Economically Important Weed Horseweed Using Integrated Data from Multiple Sequencing Platforms

et al. 2014

View full text Add to dashboard Cite

Horseweed (Conyza canadensis), a member of the Compositae (Asteraceae) family, was the first broadleaf weed to evolve resistance to glyphosate. Horseweed, one of the most problematic weeds in the world, is a true diploid (2n = 2x = 18), with the smallest genome of any known agricultural weed (335 Mb). Thus, it is an appropriate candidate to help us understand the genetic and genomic bases of weediness. We undertook a draft de novo genome assembly of horseweed by combining data from multiple sequencing platforms (454 GS-FLX, Illumina HiSeq 2000, and PacBio RS) using various libraries with different insertion sizes (approximately 350 bp, 600 bp, 3 kb, and 10 kb) of a Tennessee-accessed, glyphosate-resistant horseweed biotype. From 116.3 Gb (approximately 3503 coverage) of data, the genome was assembled into 13,966 scaffolds with 50% of the assembly = 33,561 bp. The assembly covered 92.3% of the genome, including the complete chloroplast genome (approximately 153 kb) and a nearly complete mitochondrial genome (approximately 450 kb in 120 scaffolds). The nuclear genome is composed of 44,592 protein-coding genes. Genome resequencing of seven additional horseweed biotypes was performed. These sequence data were assembled and used to analyze genome variation. Simple sequence repeat and single-nucleotide polymorphisms were surveyed. Genomic patterns were detected that associated with glyphosate-resistant or -susceptible biotypes. The draft genome will be useful to better understand weediness and the evolution of herbicide resistance and to devise new management strategies. The genome will also be useful as another reference genome in the Compositae. To our knowledge, this article represents the first published draft genome of an agricultural weed.

show abstract

Section: Discussionmentioning

confidence: 99%

De Novo Genome Assembly of the Economically Important Weed Horseweed Using Integrated Data from Multiple Sequencing Platforms

et al. 2014

View full text Add to dashboard Cite

show abstract

“…In addition, in Conyza species, several biotypes of glyphosate-resistant horseweed have shown predominately non-target-site resistance mechanisms (Feng et al 2004;Koger and Reddy 2005;Main et al 2004;Powles 2010;Zelaya et al 2004).…”

Section: Introductionmentioning

confidence: 99%

A Glyphosate Resistance Mechanism in Conyza canadensis Involves Synchronization of EPSPS and ABC-transporter Genes

2015

View full text Add to dashboard Cite

Horseweed, [Conyza canadensis (L.) Cronq.], has been the most frequent weed species to develop resistance to glyphosate in various parts of the world, including Greece. In order to investigate the resistance mechanism, susceptible (S) and resistant ®) populations collected from regions across Greece were studied. Real-time PCR was used to determine the expression levels of the key enzyme EPSPS and the four ABC transporter genes M10, M11, M7 and P3. The expression level of those genes was studied at early (1DAT) or late (4DAT) times after glyphosate treatment, applied at normal (720 g a.i. ha −1 ) and high (5.760 g a.i. ha −1 ) glyphosate rate. The proposed resistance mechanism was found not to be due to a point mutation at codon 106 of the EPSPS gene that regulates glyphosate metabolism (target-site resistance), but rather involved synchronization of the overexpression of EPSPS and ABC-transporter genes. This synchronization mechanism was based on (1) the time of induction and duration of gene overexpression, and (2) regulation by the initial glyphosate load.

show abstract

“…In addition, a number of herbicides will kill horseweed if applied to horseweed in the seedling stage (Bruce and Kells 1990;Kapusta 1979;Kapusta and Krausz 1993;Keeling et al 1989;Moseley and Hagood 1990). However, horseweed has also developed resistance to broad-spectrum herbicides, including triazines (Gressel et al 1982;Heap 2007;Pölös et al 1988;Weaver 2001), paraquat (Smisek et al 1998;VanGessel et al 2006), acetolactate synthase (ALS) inhibitors (Heap 2007), and glyphosate (Koger et al 2004;Main et al 2004;VanGessel 2001), which represent various families of herbicides and are principally used for horseweed control or suppression.…”

mentioning

confidence: 99%

“…Research to confirm GR horseweed has been conducted on small seedling plants in the greenhouse (Koger et al 2004;Main et al 2004;VanGessel 2001). However, glyphosate is often applied to large horseweed plants after they have begun to bolt.…”

mentioning

confidence: 99%

Influence of Glyphosate-Resistant Horseweed (Conyza canadensis) Growth Stage on Response to Glyphosate Applications

et al. 2009

View full text Add to dashboard Cite

Infestations of glyphosate-resistant (GR) horseweed have become widespread in the eastern United States. This biotype is problematic in no-tillage production that relies extensively on glyphosate for weed control. Because horseweed is treated at various stages of growth, a greenhouse study explored rate response of glyphosate-resistant and -susceptible horseweed at three growth stages. GR horseweed was more responsive to glyphosate at the seedling stage than at the large rosette or bolting stages. A field study evaluated GR horseweed response when treated with glyphosate at soybean planting time, POST in-crop (about 45 d after planting), or both at planting and POST in-crop. There was a cumulative effect of the at-planting followed by POST in-crop glyphosate applications. When evaluating single glyphosate applications, the at-planting application was more effective at suppressing GR horseweed than a POST in-crop application. Because glyphosate cannot control GR horseweed, this biotype should be controlled with an herbicide with an alternate mode of action and applied at the most effective timing.

show abstract

Response of Selected Horseweed (Conyza canadensis (L.) Cronq.) Populations to Glyphosate

Cited by 67 publications

References 11 publications

De Novo Genome Assembly of the Economically Important Weed Horseweed Using Integrated Data from Multiple Sequencing Platforms

De Novo Genome Assembly of the Economically Important Weed Horseweed Using Integrated Data from Multiple Sequencing Platforms

A Glyphosate Resistance Mechanism in Conyza canadensis Involves Synchronization of EPSPS and ABC-transporter Genes

Influence of Glyphosate-Resistant Horseweed (Conyza canadensis) Growth Stage on Response to Glyphosate Applications

Contact Info

Product

Resources

About