scholarly journals Biochemical and Rapid Molecular Analyses to Identify Glyphosate Resistance in Lolium spp.

Agronomy ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 40
Author(s):  
Maria Gerakari ◽  
Nikolina Cheimona ◽  
Eleni Tani ◽  
Ilias Travlos ◽  
Demosthenis Chachalis ◽  
...  

Lolium spp. are troublesome weeds mainly found in winter cereal crops worldwide, including Europe. In recent years resistant mechanisms have been evolved to several important herbicides. In this study we investigated the mechanisms responsible for conferring glyphosate resistance in some Lolium spp. populations. A holistic approach was used, based on dose-response experiments, determination of shikimic acid concentration in plant leaf tissue, as well as molecular analyses. More specifically, in three Lolium spp. populations the existence of a mutation in the Pro-106 codon of the 5-enolpyruvylshikimate-3 phosphate synthase (EPSPS) gene was investigated as well as the relative transcript levels of four ABC-transporter genes were monitored at three time points after glyphosate application. The results demonstrated that glyphosate resistance is a multifactor phenomenon. Relative transcript levels of the ABC-transporter genes were abundant at very early time points after glyphosate treatments. Dose-response experiments and shikimate analyses were in accordance with the findings of the quantitative PCR (qPCR) analyses. We suggest that relative expression ratio of ABC-transporter genes can be a useful tool to rapidly identify Lolium spp. populations resistant to glyphosate.

Weed Science ◽  
2011 ◽  
Vol 59 (2) ◽  
pp. 171-176 ◽  
Author(s):  
Leonardo Bianco de Carvalho ◽  
Hugo Cruz-Hipolito ◽  
Fidel González-Torralva ◽  
Pedro Luis da Costa Aguiar Alves ◽  
Pedro Jacob Christoffoleti ◽  
...  

Sourgrass is a perennial weed infesting annual and perennial crops in Brazil. Three biotypes (R1, R2, and R3) of sourgrass suspected to be glyphosate-resistant (R) and another one (S) from a natural area without glyphosate application, in Brazil, were tested for resistance to glyphosate based on screening, dose-response, and shikimic acid assays. Both screening and dose-response assays confirmed glyphosate resistance in the three sourgrass biotypes. Dose-response assay indicated a resistance factor of 2.3 for biotype R1 and 3.9 for biotypes R2 and R3. The hypothesis of a glyphosate resistance was corroborated on the basis of shikimic acid accumulation, where the S biotype accumulated 3.3, 5.0, and 5.7 times more shikimic acid than biotypes R1, R2, and R3, respectively, 168 h after treatment with 157.50 g ae ha−1of glyphosate. There were no differences in contact angle of spray droplets on leaves and spray retention, indicating that differential capture of herbicide by leaves was not responsible for resistance in these biotypes. The results confirmed resistance of sourgrass to glyphosate in Brazil.


2017 ◽  
Vol 40 (12) ◽  
pp. 3031-3042 ◽  
Author(s):  
Heping Han ◽  
Martin M. Vila-Aiub ◽  
Adam Jalaludin ◽  
Qin Yu ◽  
Stephen B. Powles

2011 ◽  
Vol 47 ◽  
pp. S339-S340
Author(s):  
V. Hlavac ◽  
R. Vaclavikova ◽  
M. Ehrlichova ◽  
I. Hlavata ◽  
V. Pecha ◽  
...  

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 377 ◽  
Author(s):  
José G. Vázquez-García ◽  
Sajedeh Golmohammadzadeh ◽  
Candelario Palma-Bautista ◽  
Antonia M. Rojano-Delgado ◽  
José A. Domínguez-Valenzuela ◽  
...  

Chloris distichophylla, suspected of glyphosate resistance (GR), was collected from areas of soybean cultivation in Rio Grande do Sul, Brazil. A comparison was made with a susceptible population (GS) to evaluate the resistance level, mechanisms involved, and control alternatives. Glyphosate doses required to reduce the dry weight (GR50) or cause a mortality rate of 50% (LD50) were around 5.1–3 times greater in the GR population than in the GS population. The shikimic acid accumulation was around 6.2-fold greater in GS plants than in GR plants. No metabolized glyphosate was found in either GR or GS plants. Both populations did not differ in the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) basal activity or in vitro inhibition of EPSPS activity by glyphosate (I50). The maximum glyphosate absorption was observed at 96 hours after treatment (HAT), which was twofold higher in the GS plants than in the GR plants. This confirms the first case of glyphosate resistance in C. distichophylla. In addition, at 96 HAT, the GS plants translocated more 14C-glyphosate than the GR ones. The best options for the chemical control of both C. distichophylla populations were clethodim, quizalofop, paraquat, glufosinate, tembotrione, diuron, and atrazine. The first case of glyphosate resistance in C. distichophylla was due to impaired uptake and translocation. Chemical control using multiple herbicides with different modes of action (MOA) could be a tool used for integrated weed management (IWM) programs.


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1735
Author(s):  
Candelario Palma-Bautista ◽  
Pablo Belluccini ◽  
Valentin Gentiletti ◽  
José G. Vázquez-García ◽  
Hugo E. Cruz-Hipolito ◽  
...  

Carduus acanthoides L. is an invasive species native to Europe and distributed in other parts of the world, including North and South America. In Cordoba, Argentina, control failures of this species have been reported in Roundup Ready (RR) soybean crops where glyphosate and 2,4-D have frequently been applied, although there are no confirmed reports worldwide of resistance to glyphosate and 2,4-D in this species. Dose–response tests showed multiple-resistance to both active principles. The resistant population (R) had LD50 values of 1854.27 and 1577.18 g ae ha−1 (grams of acid equivalent per hectare), while the susceptible (S) population had LD50 values of 195.56 and 111.78 g ae ha−1 for glyphosate and 2,4-D, respectively. Low accumulations of shikimic acid (glyphosate) and ethylene (2,4-D) at different doses in the R population compared to the S population support the results observed in the dose–response curves. No significant differences in leaf retention were observed for glyphosate and 2,4-D in the R and S populations. However, the use of adjuvants increased the retention capacity of herbicides in both populations. Ten alternative herbicides with seven different action mechanisms (MOAs) were evaluated and the most effective active principles were dicamba, bromoxynil, atrazine, tembotrione, flazasulfuron, glufosinate, and paraquat. These findings are the first evidence of glyphosate and 2,4 D resistance in C. acanthoides.


Insects ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 66 ◽  
Author(s):  
Valentina Mastrantonio ◽  
Marco Ferrari ◽  
Agata Negri ◽  
Tommaso Sturmo ◽  
Guido Favia ◽  
...  

Insecticides remain a main tool for the control of arthropod vectors. The urgency to prevent the insurgence of insecticide resistance and the perspective to find new target sites, for the development of novel molecules, are fuelling the study of the molecular mechanisms involved in insect defence against xenobiotic compounds. In this study, we have investigated if ATP-binding cassette (ABC) transporters, a major component of the defensome machinery, are involved in defence against the insecticide permethrin, in susceptible larvae of the malaria vector Anopheles gambiae sensu stricto. Bioassays were performed with permethrin alone, or in combination with an ABC transporter inhibitor. Then we have investigated the expression profiles of five ABC transporter genes at different time points following permethrin exposure, to assess their expression patterns across time. The inhibition of ABC transporters increased the larval mortality by about 15-fold. Likewise, three genes were up-regulated after exposure to permethrin, showing different patterns of expression across the 48 h. Our results provide the first evidences of ABC transporters involvement in defence against a toxic in larvae of An. gambiae s.s. and show that the gene expression response is modulated across time, being continuous, but stronger at the earliest and latest times after exposure.


Sign in / Sign up

Export Citation Format

Share Document