Koshevsky I. The ecologic-biological substantiation of leguminous plants protection measures against downy mildew in different soil-climatic zones of Ukraine.

This paper presents the results of research (1977-2009 years) of geographical distribution of downy mildew on legumes, symptoms of diseases manifestation in Ukraine. Physiological, biochemical and economical aspects of pathogens harmfulness when they affect peas, soybeans and spring vetch are investigated, close correlative connection between intensity of plants effection by a disease and elements of productivity reduction is determined. The thesis presents methods of direct study of pathogens, morphological and biological characteristics with histological methods. The thesis analyzes the role of climatic factors for disease appearance and progress, the speed of infectious process course, characterizes principles of hydrothermal indices selection for infectious process modeling and solution of practical problems. Models for shot- and long - term forecasting of prevalence and development of mildew on leguminous crops are developed. Their relationship to the dynamics of solar activities has been proved. Phytopathological studies under natural and artificial infectious backgrounds immunological properties of peas, soybeans and spring vetch varieties of different ecological and geographical origin are given. In this paper the physiological and biochemical, histochemical, genetic aspects of legumes varieties resistance under pathogenesis have been submitted. Using the test - set varieties of peas and soybeans, races of Peronospora pisi Syd (37 races) and Peronospora manschurica (Naum.) Syd. (11 races) were identified. The role of agrotechnical, biological, physical, chemical measures is appraised because of their effects on plant physiological state taking into consideration infected plant resistance. New achievements in fundamental and applied research of chitin-glucan complex, are considered. The possibility to increase resistance of legumes by stimulating the immune system and control plants using biologically active substances such as Micosan-N is revealed. The thesis includes various problems of leguminous plants and pathogens, new methods that oppress or hinder the development of disease and represents several scientific elaborations and proposals for protecting leguminous plants in Ukraine.