Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/2/2010
Publication Date: 12/1/2010
Citation: Cambron, S.E., Buntin, G.D., Weisz, R., Holland, J.D., Flanders, K.L., Schemerhorn, B.J., Shukle, R.H. 2010. Virulence in Hessian fly (Diptera: cecidomyiidae) field collections from the Southeastern United States to twenty-one resistance (R) genes in wheat. Journal of Economic Entomology. 103:229-2235. Interpretive Summary: The Hessian fly is the most important insect pest of wheat in the southeastern United States. Genetic resistance in wheat is the most effective method for control of this pest. However, because of the occurrence of new biotypes, Hessian fly in the field needs to be monitored periodically to provide breeders and producers information on the effectiveness of resistance (R) genes in their region. We have evaluated the effectiveness of 21 R genes with field collections of Hessian fly from across the Southeastern United States. Results documented that of the 21 R genes evaluated only 5 would protect wheat in the Southeast. These genes were H12, H18, H24, H25, and H26. These results demonstrated that effective genetic resistance to Hessian fly in the Southeast is a limited resource. Further, we proposed the risk to the durability of resistance with a single gene release strategy was high in the Southeast and that deployment of combinations of highly effective R genes was a more robust strategy to ensure durability of resistance. Our results also highlighted the need to identify new and highly effective sources of resistance if genetic resistance is to continue as a viable option for protection of wheat in the southeastern United States. Results from this study will help breeders and scientists facing the challenge of devising innovative methods to ensure the durability of resistant wheat to prevent yield loss due to Hessian fly infestation. The agricultural community (crop producers and commodity groups) will benefit from improved pest control that increases yield and quality without increasing costs.
Technical Abstract: Genetic resistance in wheat is the most efficacious method for control of Hessian fly, Mayetiola destructor (Say). However, because of the appearance of new genotypes (biotypes) in response to deployment of resistance, field collections of Hessian fly need to be evaluated on a regular basis to provide breeders and producers information on the efficacy of resistance (R) genes with respect to the genotype composition of Hessian fly in regional areas. We report here on the efficacy of 21 R genes in wheat to field collections of Hessian fly from the southeastern United States. Results documented that of the 21 R genes evaluated only 5 would provide effective protection of wheat from Hessian fly in the Southeast. These genes were H12, H18, H24, H25, and H26. While not all of the 33 identified R genes were evaluated in the present study, these results indicate that identified genetic resistance to protect wheat from Hessian attack in the Southeast is a limited resource. Historically, R genes for Hessian fly resistance in wheat have been deployed as single gene releases. While this strategy has been successful in the past, we recommend that in the future deployment of combinations of highly effective previously undeployed genes, such as H24 and H26, be considered. Our study also highlights the need to identify new and effective sources of resistance in wheat to Hessian fly if genetic resistance is to continue as a viable option for protection of wheat in the Southeast.