Simultaneous expression of 5-enol pyruvyl shikimate 3-phosphate synthase (epsps) and glyphosate oxidoreductase (gox) in transgenic canola plants towards enhancing resistance to glyphosate herbicide

Canola (Brassica napus L.) is known as one of the most important oil-producing plants worldwide that has a high food value. Today, expansion of planting area of this plant has been highly considered. The presence of weeds in canola fields causes a significant loss in crop yield and quality. So far, the most widely herbicide used to manage weeds is the broad spectrum glyphosate that targets 5 enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme. In this study, with the aim of identification of new strategies to develop herbicides-resistant plants, Glyphosate Oxidoreductase (gox) and epsps genes under the control of CaMV 35S promoter were transferred to canola seedlings with pBI121 expression vector, to develop new plants with higher herbicide resistance level. Acquired seedlings were screened and then subjected to herbicide resistance bioassay. Molecular analysis of transgenic lines through PCR and RT-PCR showed successful integration and expression of the transgene, respectively. Result showed the higher relative resistance of the transgenic lines expressing two gene cassettes compared to single gene cassette lines. This study suggests that simultaneous application of two different strategies can lead to more glyphosate-resistance to develop new genetically modified crops specifically in oilseed plants such as canola