Evaluation and Haplotype Analysis of Elite Synthetic Hexaploid Wheat Lines for Resistance to Hessian Fly

Abstract

ABSTRACTSynthetic hexaploid wheat (SHW), derived from the hybrids between tetraploid wheat (Triticum turgidum L.) and Tausch's goatgrass (Aegilops tauschii Coss.), is an excellent source of resistance genes for various pests of wheat (Triticum aestivum L.). The objectives of this study were to evaluate the elite SHW lines developed at the International Maize and Wheat Improvement Center for resistance to Hessian fly and to postulate the resistance genes present in the resistance lines. A total of 118 elite SHW lines and 35 durum wheat parents were evaluated for resistance to the Great Plains (GP) biotype of the Hessian fly. Fifty‐two of the SHW lines were highly or moderately resistant to Hessian fly. Since all of the durum parents were susceptible, the resistance genes in these SHW lines were derived from the A. tauschii D genome. The 52 SHW lines were haplotyped using eight polymerase chain reaction (PCR)‐based markers closely linked to five resistance genes (H13, H22, H23, H26, and H32) previously identified in A. tauschii. The marker analysis revealed that 32 resistant SHW lines shared haplotypes with the wheat lines containing the five known resistance genes. Nineteen resistant SHW lines had different haplotypes, suggesting that these lines may contain new genes for resistance to Hessian fly. The resistant SHW lines identified in this study will be useful for the development of wheat cultivars resistant to the Hessian fly as well as for genetic and evolutionary studies of resistance genes.