Design and construction of hairpin structure using sequence of CMV-2b gene for induction of resistance to Cucumber mosaic virus

Cucumber mosaic virus (CMV) infects more than 1300 plant species that causes reduction in yield and quality of crops. In this research, the application of the hairpin-mediated RNA silencing technology was investigated for obtaining resistance to CMV. Therefore, a fragment of 145 nt from the silencing suppressor gene of CMV was selected. The CMV sequences from NCBI were aligned and the consensus sequence was selected and synthesized. This gene sequence was cloned as sense and antisense in pFGC5941 binary vector and the recombinant vector named pFGC-2b-h. The obtained plasmid was transferred to GV3101 agrobacterium strain. Transient assay on bean (Phaseolus vulgaris) and Nicotiana benthamiana was performed by the agrobacterium containing pFGC-2b-h and six days later plants were mechanically inoculated by CMV. Fifteen days postinoculation, plants were assessed using symptoms appearance and ELISA test. Results showed that the construct can effectively reduce the symptoms and virus accumulation level. Furthermore, the results suggested that the pFGC-2b-h construct can be used to obtain transgenic plants resistance to CMV.