We previously evaluated 39 synthetic hexaploid wheat (SHW) lines (2n=42, AABBDD genome) derived from the crosses of durum wheat (Triticum turgidum L. ssp. durum, 2n=42, AABB) cultivar Langdon with different accessions of T. tauschii (2n=14, DD) and found three of them (SW8, SW34, and SW39) highly resistant to Hessian fly [Mayetiola destructor (Say)], an important insect of wheat. The objective of this study was to genetically characterize the resistance in the two SHW lines SW8 and SW34. Segregation of Hessian fly resistance in the F₂ progeny from the crosses of the two resistant synthetic lines with one susceptible synthetic wheat line indicated resistances in these two lines are controlled by a single gene. Resistant genes in these two lines are located on a D-genome chromosome because Langdon is highly susceptible to Hessian fly based on our previous evaluation. Allelism tests of these two synthetics with four of six wheat lines having Hessian fly resistant genes on the D-genome chromosomes and the genetic mapping of the resistance genes are in progress.

*Corresponding author: xiwen.cai@ndsu.edu