This Small Business Innovation Research (SBIR)Phase II project proposes to further optimize the techniques for engineering broad-spectrum disease resistance in crop plants. Protection of crops against pathogens is one of the most significant unmet needs in agriculture. Despite billions of dollars spent on fungicides and other crop protection chemicals, significant economic losses continue to occur every year. Prior Phase I work has established that overexpression of the transcription factor AtERF1 confers resistance against several fungal pathogens in Arabidopsis thaliana. The objectives of the Phase II project are to characterize AtERF1 crop homologs, to demonstrate AtERF1 function in the tomato crop, to optimize the technology by targeting expression to different tissues, to broaden the spectrum of resistance through combinatorial expression with other transcription factors, to optimize AtERF1 function by creating derivatives with enhanced activity, and to improve understanding of AtERF1 function by characterization of targets in Arabidopsis and tomato. <br/><br/>The commercial impact of this project will be significant as there is clearly a market need for conferring broad spectrum disease resistance in economically important crop plants.