164 страниц. 2010 год. LAP Lambert Academic Publishing Since Phytophthora infestans was first described as the cause of late blight disease, intense research was devoted to understand its genetics and physiology, as well as its interaction with potato. A better understanding of the molecular mechanisms underlying this plant–microbe interaction could lead to the development of new strategies to reduce crop losses and thereby benefit agricultural practices. the objectives of this study were; analyzing the genetic diversity among P.infestans isolates and certain potato genotypes using RAPD PCR, estimating the ability of serological and molecular tools in detecting P.infestans and studding the disease development in resistant and susceptible potato cultivars, investigating the role of common antigens & certain potato defense mechanisms such PR- proteins, oxidizing enzymes,reactive oxygen species, lipid peroxidation & transcription activators in relation to potato resistant against late blight pathogen.