Tracking and Managing Diseases of Floriculture Crops Caused by Oomycetes and Fungi
Biological Integrated Pest Management Unit
Project Number: 1907-22000-019-06
Specific Cooperative Agreement
Start Date: Sep 20, 2010
End Date: Sep 19, 2014
Both oomycetes and fungi can be serious pathogens of floriculture crops, causing diseases that destroy the aesthetic quality and marketability of these economically important plants. Since each production business grows numerous plant species, there are many different plant-pathogen combinations that can result in harmful diseases. Introductions of new cultivars, shifts in weather patterns, changes in cultural practices, or even changes in control efforts against other greenhouse pests can suddenly favor pathogen development and lead to explosive disease outbreaks. New disease-causing agents, including familiar but genetically different pathogens, frequently are encountered on floriculture crops due to the introductions from exotic locations. The global movement of seeds, cuttings, and plants allows global spread of pathogens, despite our best quarantine and other regulatory efforts. This project will focus on some of the more common diseases affecting floriculture crops as well as some of the newer and more unusual diseases.
We intend to develop information to help growers reduce crop losses caused by various plant pathogenic fungi and oomycetes as well as key insect pests, including important vectors of plant pathogens. New methods and tools will be developed and effective integrated management practices will be identified. The objectives are to 1) reduce crop losses caused by Pythium and Phytophthora species, 2) better understand the threat of Fusarium wilt in floriculture crops 3) develop more effective management strategies for fungi that commonly cause root rots, especially Thielaviopsis basicola and Rhizoctonia solani, 4) develop effective management programs for rust diseases on roses and chrysanthemums, and 5) improve the integration of root rot disease management practices with biologically-based IPM programs being developed for insect pests. The latest scientific methods will be employed in order to improve the success of IPM programs for floriculture crop production.
Project objectives will be addressed by testing disease management strategies—including sanitation methods and cultural practices as well as biopesticides and chemical fungicides—in greenhouse and field trials at Cornell University’s Long Island Horticultural Research and Extension Center. Research plots will be replicated and the data will be statistically analyzed. We also will collaborate closely with researchers at Oklahoma State University to improve our greenhouse sampling techniques for oomycete pathogens and to learn how to use molecular tools effectively to pinpoint the source of pathogen outbreaks within production pathways. This work will involve sampling from cooperating greenhouse operations and identifying isolates by morphological and molecular-based methods in the laboratory. Conducted in cooperation with USDA-ARS researchers at Ithaca, NY, laboratory assays and small-scale greenhouse tests will elucidate the nature of Bradysia fungus gnat/Pythium associations and the role of fungus gnats in root rot disease outbreaks and also assess compatibilities among fungicides used for control of root rot diseases and beneficial fungi (mycoinsecticides) used against insect pests.