Novel Resistance to Hessian Fly In the Wheat Line, PI 134942.

The insect pest, Hessian fly (HF) [Mayetiola destructor (Say)] causes significant wheat (Triticum aestivum L.) yield losses in many regions globally and in the USA.  Larvae feed at the base of wheat seedlings, draining the plants of nutrients.  Infested plants that are susceptible become stunted and die, and the insect completes its life cycle.  Resistant plants continue normal growth and the Hessian fly larvae die.  Derived from the durum wheat (T. durum) line PI 134942, the Purdue T. aestivum spring wheat line, P97211, has been found to be highly effective against all biotypes of Hessian fly tested.  Our objective is to determine the inheritance of Hessian fly resistance in PI 134942 and P97211, and genetically map the resistance and identify co-segregating DNA markers.  During fall 2011, 90 F₂ plants of P97211/Len (a susceptible spring wheat line) were tested to HF biotype vir13.  In spring 2012, an additional 196 F₂ plants of P97211/Len, and 147 F₂ plants of D6647 (a susceptible durum wheat line)/PI 134942, 10 F₁ plants of Len/P97211  and 10 F₁ plants of D6647/PI 134942 were tested to HF biotype vir13.  In each test, tissue was collected from phenotyped plants to be used for marker screening.  Results suggest a single gene conferring resistance is located on the short arm of chromosome 3A.  Additional SSR markers that are mapped to 3AS are being screened to more precisely locate the HF resistance gene.