Cameron Cedeno
Research Technologist
The Pennsylvania State University
University Park, PA, USA
McKenna Loney
Undergraduate Research Assistant
The Pennsylvania State University
University Park, Pennsylvania, United States
William Boone
Plant Pathology Farm Manager
The Pennsylvania State University
University Park, Pennsylvania, United States
Carolee T. Bull
Professor
Pennsylvania State University
University Park, Pennsylvania, United States
Shaheen Bibi
Postdoctoral Fellow
University of Manitoba
Winnipeg, Manitoba, Canada
Elisabeth Hodgdon
Extension Associate Regional Vegetable Specialist
Cornell University
Plattsburgh, New York, United States
Rebecca Sideman
Professor
University of New Hampshire
Durham, New Hampshire, United States
Ann Hazelrigg
Extension Associate Professor
The University of Vermont
Burlington, Vermont, United States
Arugula is a commonly grown leafy green on mixed vegetable operations in the Northeast U.S. Bacterial blight disease of arugula is caused by the pathogen Pseudomonas cannabina pv. alisalensis. There are currently no cultivar recommendations based on bacterial disease resistance available for producers in the Northeast. To make informed recommendations to growers, 26 commercial arugula cultivars were screened for resistance to P. cannabina pv. alisalensis over four greenhouse experiments, one summer field trial, and one fall field trial. The cultivars evaluated were distributed among three species of arugula: 14 Diplotaxis tenuifolia, 11 Eruca sativa, and 1 Diplotaxis erucoides. Plants were spray inoculated using a 108 CFU/ml bacterial suspension, and disease symptom severity ratings (1-6, 1= no disease, 6= symptoms on 76-100% of the most diseased leaf) for each cultivar were recorded 7, 14, and 21 days after inoculation. Area under the disease progress curve values for each cultivar were calculated and analyzed with ANOVA and Tukey HSD to compare differences in means. In all experiments, disease severity was significantly lower in all Diplotaxis cultivars when compared to the E. sativa cultivars. There was increased disease severity among Diplotaxis arugula in the summer trial compared to all other trials. Since all commercial E. sativa cultivars were identified as susceptible to bacterial blight, similar experiments will be conducted using genotypes from the USDA-ARS Germplasm Resources Information Network to identify disease resistant candidates for breeding projects.