Hessian Fly‐Resistance Gene H26 Transferred from Triticum tauschii to Common Wheat

Abstract

There is a continuing need for enhanced genetic diversity in common wheat (Triticum aestivum L.) for resistance to the Hessian fly (Mayetiola destructor Say). The objectives of this study were (i) to transfer gene for Hessian fly resistance from the accession TA 2473 of the wild diploid goatgrass T. tauschii (Coss.) Schmal. into an elite, hexaploid wheat genotype and (ii) to determine the chromosomal location of the gene. The F1 and BC1 progenies from the cross ‘Kari’/TA 2473 were male‐sterile and set very few backcross seed, but seven BC2F2‐derived lines were resistant or segregating for resistance to Biotype L of Hessian fly. Homozygous resistant BC2F4 and BC2F5 progeny within those lines were crossed to ‘Wichita’‐based stocks monosomic for six of the seven D‐genome chromosomes and to tester stocks carrying the genes H13, H22, H23, H24, and an unnamed gene, all transferred previously from T. tauschii. Segregation of F2 plants from those crosses showed that resistance derived from TA 2473 is governed by one dominant gene located on chromosome 4D. This gene, designated herein as H26, is the only Hessian fly‐resistance gene known to be located on 4D. Gene H26 conditions a high level of antibiosis to Biotype L and has been transferred into a germplasm line, KS92WGRC26, which has most of the desirable agronomic traits of its recurrent parent, Karl. Therefore, H26 is expected to be a useful addition to the set of Hessian fly‐resistance genes available to wheat breeders.