Akulov O. Biological features of Bipolaris sorokiniana (Sacc. in Sorokin) Shoemaker and diagnostics of infecting agent of root rot and black point seeds of summer barley

The objects of researches - Bipolaris sorokiniana (Sacc. in Sorokin) Shoemaker and summer barley. The purpose of researches - studying of Bipolaris sorokіnіana biological features in view of parasitism on overground and underground organs of summer barley plants and improvement of pathogens diagnostics methods under common root rot and a black point of seeds.The scientific novelty of the received results. The complex comparative research of morphological, cultural, physiological, biochemical and parasitic features of Bipolaris sorokiniana monoconidial isolates from leaves, seeds and roots of summer barley is carried out. The two forms of the pathogen - longisporous and brevisporous are revealed and quantitatively characterized; the criteria of their recognition are offered. It is shown, that a primary source of these forms renewal in life cycle of pathogen are infected seeds. The laws of B. sorokіnіana and Fusarium spp. development on the underterraneous and circumterraneous parts of summer barley areinvestigated and the method of the of helminthosporiosis and fusariosis development estimation is offered. On the 38 summer barley grades and hybrids in the same stationary conditions the comparative analysis of four the most widespread methods of black point diagnostics for the first time has been lead. Advantages and lacks of each of the researched methods are characterized. Recommendations on B. sorokіnіana quantitative diagnostics in summer barley seeds on a background of accompanying pathogens development are elaborated