Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/31/2004
Publication Date: 5/15/2004
Citation: Behura, S.K., Valicente, F.H., Rider, D.S., Chen, M., Jackson, S., Stuart, J.J. 2004. A physically anchored genetic map and linkage to avirulence reveals recombination suppression over the proximal region of hessian fly chromosome a2. Genetics. 167:343-355 Interpretive Summary: Resistance in wheat (Triticum aestivum) to the Hessian fly (Mayetiola destructor), a major insect pest of wheat, is based on a gene-for-gene interaction. The Hessian fly is one of the most destructive pests of wheat. Resistance wheat has been most effective to control this pest. The challenge for wheat resistance strategy is that Hessian fly larvae can overcome resistance after a wheat cultivar is released. The ultimate goal of this study is to reveal how Hessian fly larvae overcome wheat resistance. The present study revealed some unusual genetic behavior of the genes that putatively overcome wheat resistance. The result of this study will facilitate eventual identification of the genes that control Hessian fly virulence/avirulence.
Technical Abstract: Resistance in wheat (Triticum aestivum) to the Hessian fly (Mayetiola destructor), a major insect pest of wheat, is based on a gene-for-gene interaction. Close linkage (3+2 cM) was discovered between Hessian avirulence genes vH3 and vH5. Bulked segregant analysis revealed two DNA markers (28-178 and 23-201) within 10 cM of these loci and only 3+cM apart. However, 28-178 was located in the middle of the short arm of Hessian fly chromosome A2 wheareas 23-201 was located in the middle of the long arm of chromosome A2, suggesting the presence of severe recombination suppression over its proximal region. To further test that possiblility, an AFLP-based genetic map of the Hessian fly genome was constructed. Fluorescence in situ hybridization of 20 markers on the genetic map to the polytene chromosomes of the Hessian fly indicated good correspondence between the linkage groups and the four Hessian fly chromosomes. The physically anchored genetic map is the first of any gall midge species. The proximal region of mitotic chromosome A2 makes up 30% of its length but corresponded to <3% of the chromosome A2 genetic map.