Submitted to: International Congress of Plant Pathology Abstracts and Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/1/2003
Publication Date: 2/5/2003
Citation: CARDWELL, K., DOWELL, F.E., MITCHELL, J., RIEMENSCHNEIDER, R., SPAIDE, R., VOCKE, G. PHYTOSANITARY VS. REGULATORY RISK OF LOSSES DUE TO WHEAT KARNAL BUNT IN THE U.S.A.. INTERNATIONAL CONGRESS OF PLANT PATHOLOGY ABSTRACTS AND PROCEEDINGS. 2003.
Technical Abstract: The United States Department of Agriculture (USDA) in 1983 initiated Karnal bunt (KB) regulatory processes, and research programs in cooperation with institutions in India and Mexico. The reasons were 1) smut diseases were subject to international quarantines, 2) KB was known to be present in neighboring Mexico, 3) European Plant Protection Organization (EPPO) countries had restrictions on importation of wheat that might contain KB, and 4) little was known about the biology and potential for crop loss caused by its causal organism, Tilletia indica. In 1996, KB was detected in a few fields in southwestern USA. Since that time, annual disease surveys conducted by the USDA have shown the disease to be sporadic, causing no measurable reductions in grain yield and negligible, easily managed effects on grain quality. These results are consistent with KB research and surveys conducted over the last 20 years in India and Mexico, and now the USA. KB moves very slowly and causes no direct crop production loss, most loss being economic due to the quarantine status of the disease. KB research at USDA focuses on improving methods of detection of bunted kernels, determining longevity of teliospores in field soil, and effects of environment on spread and establishment. It is believed that this research will explain why KB continues to be a minor disease in both Asia and North America. Based on these factors, the USDA is in the process of rationalizing regulatory policy to better reflect the phytosanitary risk posed by KB.