A SYSTEMS APPROACH FOR MANAGING BACTERIAL BLIGHT OF CARROT

Bacterial blight, caused by the plant pathogenic bacterium Xanthomonas hortorum pv. carotae (Xhc), is an important seedborne disease of carrot. Our long-term goals are to improve our understanding of Xhc biology and bacterial blight epidemiology, develop and implement a suite of integrative pest management approaches for the pathogen, and inform the carrot industry on these methods to reduce risks and losses associated with the disease. Towards this end, the objectives of this project are to:Evaluate and implement sustainable IPM approaches for bacterial blight in carrot and carrot seed cropsHypothesis: An IPM approach that integrates chemical, biological, and cultural practices with model-based decision support systems will improve control of Xhc. Model Xhc aerobiology and epidemiologyHypothesis: Characterizing environmental conditions and cultural practices that contribute to Xhc dispersal will allow us to identify pathogen sources, model dispersion and dissemination of the pathogen, and forecast and mitigate risk factors that promote the disease.Visualize plant infection processes to determine the nature and extent of Xhc colonization in carrotsHypothesis: Understanding the processes of plant and seed infection by Xhc will inform chemical, biological, and post-harvest management practices.Assess the population genomic diversity of Xhc in the U.S. to infer sources of inoculum and dispersal potential of bacterial blight in carrot and carrot seed production systemsHypothesis: Characterizing the genomic diversity and structure of Xhc across diverse geographic areas and sources will improve our understanding of inoculum sources and the extent of seedborne pathogen dispersal in carrot production systems.Calculate the economic impact of bacterial blight and associated management practices on carrot seed stakeholdersHypothesis: Increasing grower and stakeholder knowledge of the economic impacts of bacterial blight in seed production systems will foster the evaluation, refinement, and adoption of coordinated IPM practices to reduce the impact of Xhc on carrot and carrot seed production.