Object: corn breeding for resistance to a range of common harmful organisms. Objective: theoretical justification, development and improvement of methodological approaches of heterosis corn breeding for resistance to pathogens and pests; development of a competitive corn hybrid model with increased adaptability, high resistance to biotic factors and determination of ways of its fulfillment; practical application of prediction of the genetic value of lines in terms of disease resistance in breeding; use of systemic analysis to select pairs for crossing. Methods: general scientific, special (field, laboratory), statistical. Novelty: for the first time in Ukraine, methodical approaches of prediction of the value of corn lines for the breeding of high-yielding and resistant to diseases and pests hybrids based on analytical models of dependence of F1 hybrid resistance on resistance of maternal forms and manifestations of its donor properties in the hybrid and a model of pathogen resistance of F1 corn hybrids on basic breeding features such as the growing season length and its structure, productivity and its components, morphological traits, which allows defining optimal options upon selection of parental pairs to create corn hybrids that would be resistant to fusarium stem rot were theoretically justified and developed. Specificity of the genetic control of resistance of corn hybrids to smut and fusarium pathogens was determined by the reaction norm of hybrids to pathogen penetration via analyzing parental lines and hybrids as well as F1, F2 and F3 generations. A donor property index (DPI) corn parents was developed; specificity of manifestation of their general combining ability was established; parameters (DPI), which would enable producing hybrids with high field resistance to the pathogen, were determined for maternal lines by resistance to Fusarium. Results: five methods, of them, two methods of artificial infection of corn plants that reliably detect resistant forms, two methods that increase the yield capacity of corn, and one that assess the quality control of corn line creation, were developed. Twenty lines were registered with the NCPGRU as sources and donors of resistance and commercially valuable traits. Six collections with commercially valuable traits and resistance to diseases and pests were formed: a trait collection of corn lines with complex resistance to diseases; a working collection with group and complex resistance to harmful organіsms; and collections with polystichia, long ear, and productivity. Twenty eight corn hybrids belonging to different ripeness groups were created and recorded in the State Register of Varieties Suitable for Dissemination in Ukraine. Degree of Implementation: scientific results are used in breeding programs and corn seed production at the Plant Production Institute nd. a VYa Yuryev NAAS, Bukovina State Agricultural Experimental Station NAAS; they are used for prediction, diagnostics and phytosanitary analysis of risks in the Directorate of Phytosanitary Security of the State Service of Ukraine on Food Safety and Consumer Protection in the Kharkiv region as well as in the educational process of Sumy and Kharkiv National Agrarian Universities, Karazin Kharkiv National University, and the hybrids created are grown on the areas of 500,000 ha in Ukraine and of to 5,000 ha in the Kharkiv region, giving up to 11.5 t / ha under industrial environments. From 2011 to 2013, mid-early hybrid 'Vympel MV' and mid-ripening hybrids 'Kredit MV' and 'Donor MV' were recognized as national standards in state variety trials in Ukraine. Twenty eight copyright certificates on corn hybrids and five utility model patents were received. Scope of Implementation: scientific institutions of NAAS and the Ministry of Agrarian Policy and Food of Ukraine, higher educational establishments, agrarian enterprises of Ukraine
