NC503: Host Plant Control Resistance to and Best Management Practices for Karnal Bunt of Wheat
- September 30, 2002 to October 01, 2004
- Administrative Advisor(s):
- NIFA Reps:
Statement of Issue(s) and Justification:Karnal bunt (KB) of wheat, caused by Tilletia indica, was introduced into the United States in 1996 into small areas in Arizona, Texas and California. This is a serious quarantine pathogen, with over 70 wheat importing countries requiring certification that wheat is free from T. indica and comes from an area not known to be affected by the pathogen. There is zero tolerance for the presence of the pathogen. APHIS has managed the quarantine of the affected areas and after a 1997 spread to two counties in central Texas, there had been no further spread of KB. However, starting in May 2001, the pathogen was detected in grain elevators in northern Texas. It has now been found in four new counties in Texas just south of the Oklahoma border. KB is now at the southern end of the nearly continuous wheat belt that extends from Texas to Canada. Spread of this pathogen into the main winter and spring wheat growing regions of the US could result in the loss of a major share of foreign markets for US wheat growers. This would have a catastrophic impact on the economies of the mid west and Great Plains states.
Types of Activities:This rapid response activity will bring researchers together from, initially, Texas, Oklahoma, Kansas, Nebraska and Colorado to plan and begin implementing an aggressive program to neutralize the potential impact of this pathogen on the region. Initial discussions on managing this new turn of events for KB were held at a regional meeting of the American Phytopathological Society in Manhattan, KS, in June 2001. Two broad areas of research needs were identified. First, a set of "best management" practices must be developed. These will have the objectives of reducing potential for large-scale epidemics in presently contaminated areas, and reducing the likelihood of spread into new areas. This will require field and laboratory studies on the basic biology of the pathogen, its life cycle under the range of environments present across the wheat belt, and the potential for large-scale losses. It is believed that this should be considered a minor disease. If these study bare (bear?) out these impressions, then this information would provide additional support for US negotiators attempting to remove the quarantine restrictions associated with this pathogen.
The second area of research to be undertaken by the group will be development of high levels of resistance and immunity to the pathogen in wheat. Initially, efforts will focus on accelerating the progress in incorporating newly identified QTLs for T. indica into wheat using marker-assisted selection. Longer range projects will focus on generating novel resistance in the crop, such as that derived from non-hosts such as rice and maize. This effort will no-doubt include major efforts at understanding the pathogen, its genetics, and its specificity for wheat.
- Bring scientists together from wheat growing states in the mid-west and Great Plains threatened by KB to plan a coordinated. research program
- Create a multistate research plan for developing best management practices and highly KB resistant wheat varieties.
- Create a platform from which to develop a global effort on KB management and resistant variety development.
Expected Outputs, Outcomes and/or Impacts:Timely initiation of a coordinated, multistate effort on KB should slow the spread of the pathogen into the wheat belt. Before significant spread has occurred, moderately resistant varieties should be deployed throughout the region, further impeding spread. Release of highly resistant varieties will eliminate the problem of KB and insure the continued livelihoods of wheat farmers and maintain the agricultural economies of wheat-growing states.
List of Participants:Include a completed Appendix E.
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