Integrated Management of Late Blight in Tomato Using Host Resistance, Reduced Risk Fungicides and Disease

Developing an integrated disease management program

Late blight is a disease that tomato and potato growers in Pennsylvania are concerned about each year. With the recent widespread outbreaks of late blight in PA and across the Northeast in 2009 and yearly since then, late blight is now also a major concern for home and community gardeners. Host resistance is one of the primary disease management tools for both conventional and organic growers. Three major late blight disease resistance genes have been identified and incorporated into tomato cultivars that are now commercially available. Some of these include ‘Mountain Magic’, ‘Mountain Mert’, ‘Plum Regal’ and ‘Defiant’. Research at Penn State has resulted in the identification of another resistance gene and a number of late blight resistant germplasm lines have been developed. The objective of this project is to evaluate and compare the disease response of these newly developed lines when coupled with different fungicide and biopesticide programs that are applied using a late blight fungicide scheduling program that is run and delivered through the Pennsylvania Pest Information Platform for Extension and Education (PA-PIPE), an information technology platform. The forecasting model is based on knowledge of the pathogen biology and epidemiology (spread or movement). These models enable growers to time the application of fungicides based on when environmental conditions are favorable for the pathogen and disease development rather than on a schedule based on calendar dates. It has been well documented by researchers that growers can improve yields, reduce fungicide costs and environmental impact by eliminating unnecessary fungicide applications. Typically, these models are run using weather data collected from individually deployed weather stations. Recent advances in meteorological forecasting and information technology (IT) have made it possible to run these models using weather data that is interpolated between existing public-domain weather stations and display the model results on web-based platforms.

The development of an integrated disease management program that capitalizes on the use of resistant cultivars to reduce the number of fungicide applications needed and to make knowledge-based fungicide application decisions will benefit both conventional and organic tomato growers in Pennsylvania and across the Northeast region. 

Two identical trials have been established at the Russell E. Larson Research and Education Center and in a commercial tomato production field in Northumberland County in collaboration with Furmano Foods. The project is being funded by the USDA/NIFA Pest Management Alternatives Program Project # 2011-02145. A second year of trials are currently being conducted in 2013.


About the Researcher:
Beth Gugino is an assistant professor of vegetable pathology in the Department of Plant Pathology and Environmental Microbiology at Penn State. Her applied research and extension program focuses on the diagnosis, monitoring and forecasting of vegetable disease outbreaks to provide timely in-season information growers can use to make informed disease management decisions; development and evaluation of innovative, sustainable disease management strategies that can be cost-effectively incorporated into integrated pest management programs by growers and evaluation of the efficacy of conventional fungicides, biochemical and microbial biopesticides for in-season management of important and emerging disease of vegetable crops in Pennsylvania. 

Contact Information:


Phone:  814-880-8939