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PhD student position in herbicide resistance with Laval University, Qc, Canada

Description of Duties

Dr Yosra Menchari (Phytology Department, CRIV, FSAA, Laval University in Québec City, Canada) and Dr Martin Laforest (Agriculture and Agri-Food Canada) labs are looking for a motivated candidate for a three-years PhD to join their labs. The candidate will benefit from a dynamic and multidisciplinary research environment and acquire strong skills in transcriptomics, bioinformatics and weed science. Herbicide resistance is the most important trait illustrating the capacity of plants to adapt to selection pressure exerted by humans. To counter the development of resistance, or at least manage it and limit its consequences when it is already established, it is essential to understand the modalities of evolution and selection of this trait. An essential first phase is therefore the identification of the genes governing this resistance, then the development and use of molecular markers allowing rapid characterization of the underlying mechanisms. In Avena fatua L., an hexploid species (2n = 6x =42), several copies of the resistance genes exist adding a level of complexity to the study of resistance mechanisms. Three copies of the acetyl coenzyme A carboxylase gene and five mutations (Ile1781 Leu, Trp1999Cys, Trp2027Cys, Ile2041Asn and Asp2078Gly) conferring resistance to group 1 herbicides were identified. In the acetolactate synthase gene, only two substitutions, Ser653Thr and Ser653Asn, conferring resistance to group 2 herbicides are reported in wild oats. Preliminary results showed that these mutations were present are low frequencies which suggest that non-target-related mechanisms (NTSR), such as metabolism and whose genetic basis are still unknown, are also involved in resistance to group 1 and 2 herbicides in wild oats. Recent developments in next-generation sequencing (NGS) technologies have paved the way for the study of resistance mechanisms in weeds with complex determinism such as NTSR. One approach of choice is quantitative transcriptome sequencing, also known as RNA-Seq. The student’s mission will be to 1/ Study the metabolism of Gr1 and Gr2 herbicides and determine the possible involvement of P450 and GST enzymes in resistance 2/ identify and isolate the gene(s) involved in NTSR (RNA -seq and RT-qPCR).
• A master’s degree in biology, agronomy, bioinformatics and/or molecular biology.• Computational skills and basis knowledge on program R would be an asset.• Autonomy and rigor

Type of position

PhD student position


25 000$



Department of plant science, Faculty of Agriculture and Food Sciences, Laval university, Québec (QC), Canada

Closing Date


Date Position Available

Laval university
Department of plant science, Faculty of Agriculture and Food Sciences, Laval university, Québec (QC), Canada https://www.fsaa.ulaval.ca/en/faculty/departments-school/plant-science-department