Submitted to: Biological Invasions
Publication Type: Review Article
Publication Acceptance Date: August 24, 2007
Publication Date: July 9, 2008
Citation: Rossman, A.Y. 2008. The impact of invasive fungi on agricultural ecosystems Biological Invasions. 92:1376-1386. Technical Abstract: Invasive fungi and other non-indigenous plant pathogens have had a significant effect on American agriculture for hundreds of years. At present crop loss due to invasive plant pathogens especially fungi is estimated at $21 billion per year in the U.S., greater than that caused by non-indigenous insects. Plant pathogenic fungi are difficult to detect and thus knowledge of which fungi pose a threat is essential to prevent their entry. Examples are presented of invasive fungi of agricultural commodities introduced into the United States. In all cases two factors have been crucial, specifically, the pathway through which these fungi have entered, and systematic knowledge to prevent and respond to the new invasive species. Historically important plant pathogens such as black stem rust of wheat still cause considerable damage while others such as late blight of potatoes appear to be having a resurgence. Known previously in South America, the virulent species of soybean rust appeared in the U.S. in 2003 but has not been as devastating as anticipated. Plant pathogenic fungi on specialty crops such as daylily, gladiola and chrysanthemum are threatened by rust fungi recently found in the U.S. apparently brought in on infected germplasm. A crisis in the export of U.S. wheat occurred in the late 1990’s when the molecular diagnostic test for Karnal bunt gave a false positive response to closely related but previously unknown species. Several potentially dangerous plant pathogens of crop plants have not yet invaded the U.S. so it is critical that meticulous surveillance be conducted as plant material enters the U.S. but also where this material is grown prior to shipment of agriculture commodities.