Management of Pathogens For Strawberry and Vegetable Production Systems

The long-term objectives of this project are to develop disease management strategies for diseases of economic importance of strawberries and vegetables. The two overall objectives of the current project extend from the need to deliver and evaluate alternative approaches for management of these important pathogens, as well as to develop and deploy molecular diagnostic tools for their management. The project subobjectives examine cultural, biological, and genetic approaches for management of plant pathogenic fungi and oomycetes, including Verticillium dahliae, Peronospora effusa, and Macrophomina phaseolina, and provide molecular diagnostic tools to monitor populations of Fusarium oxysporum f. sp. fragariae, P. effusa, Phytopthora species, and M. phaseolina. We will focus on these following major objectives and subobjectives during the next five years. Objective 1: Optimize delivery and evaluate performance of cultural and biological methods, management practices, and genetic approaches for management of pathogens, including those currently mediated by soil fumigation. Subobjective 1A: Identify genes of Verticillium dahliae required for the initial stage of lettuce root infection. Subobjective 1B: Identify genetic alternatives for resistance to downy mildew of spinach caused by Peronospora effusa. Subobjective 1C: Identify edaphic factors that influence long term or reduced survival of soilborne fungi. Subobjective 1D: Determine the correlation between genotype of Macrophomina phaseolina and virulence on strawberry. Subobjective 1E: Assemble a high quality reference genome for M. phaseolina and identify genes associated with host specificity. Objective 2: Develop rapid and accurate molecular diagnostic tools for the identification of emerging diseases of strawberries and vegetables, and use these tools in the development of disease management strategies. Subobjective 2A: Identify population genetic markers, diagnostic markers and develop tests for rapid identification of Peronospora effusa, the downy mildew pathogen of spinach. Subobjective 2B: Develop molecular tools for identification and detection of Oomycete plant pathogens. Subobjective 2C: Develop molecular tools for detection and soil quantification of Macrophomina phaseolina and Fusarium oxysporum f. sp. fragariae.