Resistance of Transgenic Potato Expressing Intergenic Sequence of Potato Leafroll Virus

The intergenic sequence (IS) cDNA of Potato Leafroll Virus (PLRV) Chinese isolate was constructed into transformation binary vector pROK2 in positive or negative direction, then introduced into the commercial potato cultivar Desiree via Agrobacterium tumefaciens mediated gene transfer. Kanamycin resistance, PCR amplification of transgenic lines showed that intergenic sequence of PLRV Ch was integrated into the genome of potato plants. The transgenic lines were transplanted into the screen house, then inoculated with PLRV by viruliferous Myzus persicae Sulz. After inoculation, the symptom development was observed and the virus titer was detected by ELISA. Results showed that the transgenic plants displayed slight or no symptom. The average PLRV titer in the transgenic lines was lower than the untransformed plants. The transgenic lines expressing sense RNA reduced PLRV titers about 43%～72% in comparison with untransformed plants, while the transgenic lines expressing antisense RNA reduced about 72%～86%. It