The response of transgenic Brassica napus with aroA gene to glyphosate treatment

Rapeseed (Brassica napus) is one of the most important oil seed crops in the world. The weeds are the most important threats to cultivating this plant. Glyphosate is a general herbicide that inhibit the EPSPS enzyme. One of the most effective methods to make glyphosate herbicide resistance is the transformation of the EPSPS enzyme-encoding gene. In the present study, a 3-point mutation in the E. coli aroA gene was created and then this gene with a wild-type gene was cloned in the pUC18 and pBI121 plasmids and transformed to the RGS003 spring straw cultivar of rapeseed by the Agrobacterium tumefaciense strain LBA4404 strain. The gene was expressed with the CaMV35S promoter and NOS terminator. Gene cloning in cloning and expression vectors, plant transformation confirmation through PCR and other molecular tests were carried out. In this research, 142 independent T1 transgenic lines were screened for glyphosate treatment and then 10 lines were selected for later tests in the T2 generation. Seeds of transgenic T2 generation under in vivo and in vitro conditions were studied in a factorial experiment in different concentrations of glyphosate herbicide. The percentage of burn and some morphological traits such as plant height, number of branches, number of pods per sub-branch, number of pods per main branch and number of pods per plant were measured. The results showed that transgenic plants can tolerate glyphosate herbicide up to 76.8 mM, while the control plant has a lifetime of 0, 1.2, 2.4 mM.