CHRISTOVA, P., R. BATCHVAROVA and N. CHRISTOV, 2016. Expression of four transgenes in one tobacco line. Bulg. J. Agric. Sci., 22: 437–441
Pyramiding of four transgenes in one tobacco line led to a complex resistance against two viruses (TSWV, PVY) and one bacterial pathogen (Pseudomonas syringae pv. tabaci), as well as the herbicide Glean®. Expression analyses of the corresponding transgenes (Np, CP, ttr and ahas 3R) were performed with selected tobacco lines of the cross 2002. The RNA gel blot hybridization analyses of all tested tobacco plants showed an expression of the ahas 3R gene, but no signal was detected for the other three transgenes. Expression of the Np, CP and ttr genes was detected by RT-PCR analyses, suggesting low level of accumulation of the corresponding mRNAs in the transgenic tobacco lines. Involvement of RNA silencing as a mechanism of resistance to plant pathogens is discussed.