Poster Session: New and Emerging Diseases-Fungi and Oomycetes

422-P

Probability of Magnaporthe oryzae (Triticum pathotype) introduction into the United States: A quantitative pathway analysis.
C. D. CRUZ (1), J. P. Stack (1), R. D. Magarey (2), G. A. Fowler (3)
(1) Kansas State University, Manhattan, KS, U.S.A.; (2) North Carolina State University, Raleigh, NC, U.S.A.; (3) USDA-APHIS-PPQ-CPHST-PERAL, Raleigh, NC, U.S.A.

Wheat blast, caused by the Triticum pathotype of Magnaporthe oryzae (Mot), has not yet been reported outside of South America. Wheat is a major crop in the United States (U.S.) and blast can cause serious yield losses. Thus, it is important to understand the potential for its entry and establishment in the U.S. Historical data suggest that human activities are responsible for most introductions of plant pathogens. Since Mot is seed-borne, contaminated grain may be an important pathway for introduction. The purpose of this study was to estimate the probability of Mot entry and establishment in the U.S. associated with the importation of wheat grain from two at-risk areas in South America. Probabilistic models for Mot entry and establishment were constructed. Monte Carlo simulations were run using the @Risk software to determine the probability of wheat blast entry and establishment as a consequence of grain importation. The NAPPFAST modeling system was used to create risk maps based on climate to identify U.S. areas suitable to pathogen establishment. These maps were used to inform the probabilistic model for entry and establishment. Our model results can be used to inform regulatory policy for U.S. wheat imports from at-risk countries. Preparedness plans for early detection, accurate diagnosis, and effective mitigation should be developed.
Keywords: Fungus, Cereals-Grains, Wheat