Generation of transgenic tobacco plants with immunity against a broad spectrum of Potato virus Y strains

Potato virus Y (PVY) is one of the most important plant viruses affecting tobacco fields in Golestan، Mazandaran and Guilan provinces (Iran). Given the lack of insecticide impact in reducing infection to PVY، breakdown of the natural resistance resources by certain strains and the problems with traditional breeding methods، the use of alternative methods to generate PVY resistant tobacco by pathogen-derived resistance could be considered as a method for reducing the damages. The objective of this study was to produce transgenic tobacco plants with resistance against a diverse spectrum of PVY isolates from different strains. A 472 bp fragment of the genome of an Iranian PVY isolate including the partial nucleotide sequences of CP and 3''UTR regions was used for constructing a hairpin structure for PVY resistance. This construct was used for Agrobacterium-mediated transformation of tobacco variety Wisconsin 38. Following transformation، 61% of the resulting transgenic plants in T0 were resistant to PVY and the inheritance of resistance to the next generation of nine different lines was confirmed using DAS-ELISA which confirmed the immunity in all tested plants. One of these lines was tested against 12 different PVY isolates، including four Iranian and eight foreign ones، and the immunity against PVY was confirmed based on the lack of symptoms and the results of DAS-ELISA and RT-PCR tests. The results showed that the hairpin construct had a high-performance for generating transgenic tobacco plants with resistance against different PVY strains.