Professor Fayetteville State University Raleigh, North Carolina
Body of Abstract: Common wheat (Triticum aestivum) is one of the most important staple crops in the world. Hessian fly (Mayetiola destructor) is a destructive insect pest that infest wheat seedlings, causing significant yield loss. Using plant resistance has been the most effective practice to control Hessian fly, however, high temperature compromises wheat resistance to Hessian fly. This study aims to investigate how different high temperatures affect wheat resistance and if wheat plants recover their resistance after removal of the high temperature. To this end, wheat resistant cultivar ‘Molly' containing the R gene H13, was infested with an avirulent Hessian fly biotype GP. The plants were treated at 30°C and 35°C, respectively for 24 hours starting at different time points before and after the initial attacks (zero-time point) by the larvae of Hessian fly. The resistance efficiency and intensity of defense responses in wheat plants were measured by the percentage of susceptible plants and the percentage of live insects, respectively. Our results suggested that high temperatures decreased the efficiency of wheat resistance to Hessian fly, and that wheat plants could recovered their resistance to a certain degree when the high temperature was removed. The findings shed lights on our understanding of the complexity of the high temperature-induced loss of host plant resistance to insects.