Full Text                                                                            Full-Text Online        Conversion of compatible plant-pathogen interactions into incompatible interactions by expression of the Pseudomonas syringae pv. syringae 61 hrmA gene in transgenic tobacco plants Shen. S      Li. Q      He. S. -Y      Barker. K. R      Li. D      Hunt. A. G       Plant Journal ;  2000  [Vol.23]  Pages:205-213 Abstract The hrmA gene from Pseudomonas syringae pv. syringae has previously been shown to confer avirulence on the virulent bacterium Pseudomonas syringae pv. tabaci in all examined tobacco cultivars. We expressed this gene in tobacco(Nicotiana tabacum cv. KY14) plants under the control of the tobacco Δ0.3 TobRB7 promoter, which is induced upon nematode infection in tobacco roots. A basal level of hrmA expression in leaves of transgenic plants activated the expression of pathogenesis-related genes, and the transgenic plants exhibited high levels of resistance to multiple pathogens: tobacco vein mottling virus, tobacco etch virus, black shank fungus Phytophthora parasitica [Phytophthora nicotianae var. parasitica] isolate 62, and wild fire bacterium Pseudomonas syringae pv. tabaci. However, the hrmA transgenic plants were not significantly more resistant to root-knot nematodes. Our results suggest a potential use of controlled low-level expression of bacterial avr genes, such as hrmA, in plants to generate broad-spectrum resistance to bacterial, fungal and viral pathogens. Keywords disease resistance hrp avr apoptosis systemic acquired resistance hyper sensitive response