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ARS Home » Southeast Area » Charleston, South Carolina » Vegetable Research » Research » Publications at this Location » Publication #382202

Research Project: Biology, Etiology and Host Resistance in Vegetable Crops to Diseases and Nematodes

Location: Vegetable Research

Title: A diagnostic guide for Phytophthora capsici infecting vegetable crops

item PARADA-ROJAS, C - North Carolina State University
item GRANKE, L - Corteva Agriscience
item Naegele, Rachel
item HANSEN, Z - University Of Tennessee
item HAUSBECK, M - Michigan State University
item Kousik, Chandrasekar - Shaker
item MCGRATH, M - Cornell University
item SMART, C - Cornell University
item QUESADA-OCAMPO, L - North Carolina State University

Submitted to: Plant Health Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/19/2021
Publication Date: 8/30/2021
Citation: Parada-Rojas, C.H., Granke, L.L., Naegele, R.P., Hansen, Z., Hausbeck, M.K., Kousik, C.S., Mcgrath, M.T., Smart, C., Quesada-Ocampo, L.M. 2021. A diagnostic guide for Phytophthora capsici infecting vegetable crops. Plant Health Progress. 22:404-414.

Interpretive Summary: Many vegetable crops are grown across the United States and serve as an important source of nutrition for human health and development. Many of these vegetable crops are attacked by pests and diseases leading to extensive damage and crop loss. In recent years, an old, but re-emerging fungal pathogen called Phytophthora capsici has been causing serious problems in vegetable crop production across many states in the United States. This plant pathogen can cause severe losses in crops such as pepper, pumpkin, watermelon, squash's, cucumber, lima bean and others. A group of scientists from various Universities and USDA ARS have pulled together a document called as a diagnostic guide to help inform plant disease diagnostic clinics and growers on how to identify and diagnose the disease caused by this plant pathogen. The information will be useful for public and private diagnosticians, crop scouts, university researchers, and extension personnel for identifying the diseases caused by the plant pathogen on various vegetable crops.

Technical Abstract: Phytophthora capsici is an oomycete pathogen causing economically important diseases in a wide range of hosts worldwide including cucurbitaceous, solanaceous, and fabaceous crops. All plant parts, crown and roots, or only the fruit may be affected depending on the host, and symptoms can range from wilting to rot and plant death. Considered a hemibiotroph, P. capsici can be cultured in artificial media and maintained in long term storage. In this diagnostic guide, we describe methods to identify P. capsici infection based on disease symptoms and pathogen signs. We also outline methods for molecular identification, pathogen isolation, storage of single-sporangium cultures, and pathogenicity testing.