Wheat genetic control of Hessian fly (Diptera: Cecidomyiidae) in Morocco

Abstract

Hessian fly, Mayetiola destructor (Say), causes about 30% yield reduction on both durum wheat and bread wheat in Morocco. Major effort has been put on host plant resistance for control of this pest. Field and greenhouse experiments demonstrated that resistance genes H5, H11, H13, H14H15, H21, H22, H23, H25, and H26 are very effective. They all express antibiosis as a mechanism of resistance, whereby first instars die after they start feeding on plants carrying resistance genes. By contrast, H7H8 and H9 are only moderately resistant against Hessian fly in Morocco. Five other sources of resistance in bread wheat were identified: Massira, BT92P1.20: NS732/Herm, L222, L254 and ADC14. All of these resistance genes have been incorporated into Moroccan wheats. Two bread wheat cultivars, Saada (H5) and Massira (tolerant), were released to farmers in 1989 and 1994, respectively. Two bread wheat lines carrying H13 and H22 genes and L222 are in registration yield trials. No source of resistance for Hessian fly in durum wheat was identified. H5 and H11 genes, located on the A genome, have been transferred from bread wheat to drum wheat. H21 and H25 genes, located on B genome, are being transferred from bread wheat to durum wheat.