Research Description:

Does Cytokinin Play a Role in Pathogen Resistance in Transgenic Petunia?

I intend to compare the resistance of wild-type petunia and the resistance of SAG:IPT transgenic petunia to infections by various bacterial and fungal pathogens. SAG:IPT includes a senescence associated gene promoter attached to the gene producing isopentenyl transferase, the rate-limiting enzyme in cytokinin synthesis. This means that when the plant is triggered to senesce, this gene becomes active and produces cytokinin, a plant growth hormone involved in several aspects of plant development. It has been observed that plants containing this gene (for cytokinin over-expression) possess several unusual and potentially valuable traits. One such trait involves apparent resistance to Cercospora, a common fungal pathogen affecting petunia. It would seem that the plants containing the SAG:IPT gene are demonstrating a role for cytokinin in plant defense. Work is currently being done to better characterize this interaction with Cercospora. I hope to better characterize the performance of the SAG:IPT transgenic plants in the presence of pathogens as well as to better characterize the pathogen defense mechanisms in petunia as they relate to senescence and cytokinin production.