Studies on the Nature of Resistance to Orange Rust In Some New Egyptian Wheat Varieties

In the present study ,F2 monosomic analysis in the seedling stage was employed to locate gene (s) of resistance, to race 57,and 77 on specific chromosome (s) in Giza 155 and Giza 157, Egyptian wheat varieties.as susceptibility and resistance are the net results of the interaction between hosts and parasites, chemical analysis of resistant and susceptible plants previously exporsed to the infection processes can a clear idea about the nature of this interacton.for this reason,the present study included chemical analysis of samples from resistant and susceptible plants that have or lack specific resistant genes as determined by monosomic analysis.