Preparation of a construct to establish simultaneous resistance against three PLRV, ‎PVX and CMV viruses in potato by RNA silencing method

Potato is the world's fourth-largest food crop after maize, wheat, and rice. Potato is seriously affected by both single and mixed viral infections because of vegetative propagation. In plants, RNA silencing is a protective mechanism against viral infections. Some researchers have been used RNA silencing technique to silence viral genes, but ultimately, due to the activity of viral RNA silencing-suppressor proteins, the resistance of plants is broken down and the virus can replicate and make the damage. The purpose of this study was to provide simultaneous resistance to three important viruses including Potato X Virus, Potato Leafroll Virus, and Cucumber Mosaic Virus. From genes corresponding to proteins of suppressoer of RNA silencing in these viruses (P0, P25 and 2b, respectively), a fragment was amplified with specific primers by PCR and ligtaed to each other. The recombinant final fragment was cloned in the form of sense and antisense orientations with an intron between them, in pFGC5941 plasmid under 35S promoter to produce a hairpin RNA after transcription in plant. The T-DNA of recombinant hairpin vector was transformed into potato (cv. Agria) genome by Agrobacterium. The obtained transgenic plants were screened by PCR to confirm the presence of the transgenes. The resistance of selected tansgenic lines will be assessed against three viruses.