Using of mathematics methods in studying sunflower reactions on pathogenic organisms

It is shown on the base of literary data and results of author's researches that quantitative approaches with usage of mathematics methods allow' increasing the efficiency of researches of cultivated plant reactions on pathogenic organisms. It is shown on the number of concrete examples that mathematics simulation allows to get results, which can’t be obtained on the base of qualitative and semi-quantitative research methods. Opportunities of mathematics description of development of plant affection process by pathogens, forecast of epiphitoties, dependence of yield losses of sowing affection extent in different agroecological conditions are demonstrated. It is necessary for calculation of harmfulness threshold in various economic situations. Besides that opportunity and extent of influence of breeding on polygene-controlled resistance to pathogen, method of estimation genotype tolerance to disease is proposed.