ARS | Publication request: ANALYSIS OF A WHEAT DEFENSE-RESPONSE GENE INDUCED BY HESSIAN FLY LARVAE AND TREATMENT WITH BENZOTHIADIAZOLE AND SALICYLIC ACID

Submitted to: Plant and Animal Genome
Publication Type: Abstract Only
Publication Acceptance Date: January 1, 2002
Publication Date: N/A

Technical Abstract: A gene-for-gene interaction occurs between wheat and the Hessian fly, where products of wheat resistance genes are believed to interact with products of larval avirulence genes and lead to incompatibility. Incompatible interactions in wheat containing the H9 gene, conferring resistance to Biotype L Hessian fly, result in a rapid increase in Hfr-1 (Hessian fly response-1) mRNA. Hfr-1, a wheat defense-response gene, was monitored by Northern blot analysis during both compatible and incompatible interactions initiated by attempted feeding of first-instar Hessian fly larvae. In addition, the specificity of the Hfr-1 response was tested by subjecting wheat plants to chemical inducers of several defense-response pathways as well as to wounding and desiccation. Hfr-1 expression increased dramatically after treatment with benzo(1, 2, 3)thiadiazole-7-carbothioic acid S-methyl ester (BTH), and, to a lesser degree, salicylic acid (SA). BTH and SA induce systemic acquired resistance genes in dicots. Therefore, Hfr-1 may be similarly regulated. No induction of Hfr-1 was observed in seedlings treated with methyl jasmonate, abscisic acid, or in plants subjected to wounding and desiccation stress. Inhibitory cross-talk between defense-response pathways may explain why Hfr-1 is not induced in situations other than incompatible wheat/Hessian fly interactions and treatment with BTH and SA.