ARS | Publication request: Molecular Aspects of Hessian Fly Resistance in Wheat

Submitted to: International Plant Resistance to Insects Workshop Abstracts & Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: February 1, 1998
Publication Date: N/A

Technical Abstract: Syntenic relationships between the wheat and rice genomes are well established. Taking advantage of this genome conservation, we are mapping Hessian fly resistance gene H20, on durum wheat chromosome 2B, with respect to insect resistance genes on rice chromosomes 4 and 7. A set of RFLP markers, that has been mapped in both wheat and rice, is being used for the comparisons. Tests were conducted to determine the best conditions for scoring the resistance phenotypes within our mapping population, revealing that H20 is temperature sensitive. In addition, the resistant (Jori -H20) and susceptible (D6647) parents of our mapping population showed greatest phenotypic differences when infested with biotype B of the Hessian fly. Although many resistance genes, including H20 , are considered to operate in a gene-for-gene manner, systemic acquired resistance is also an important component of plant defense. We identified a gene whose induction corresponds with the initiation of feeding by avirulent Hessian fly larvae on resistant wheat seedlings. Our gene is 80% homologous to and has a similar temporal expression profile to WCI-1, a wheat gene that is induced by (benzo(123) thiadiazol-7-carbothioic acidS-methyl ester). BTH induces systemic resistance to Erysiphe gramimis, Puccinia recondita and Septoria spp. infection.