ВПЛИВ PSEUDOMONAS SYRINGAE НА IНТРОДУКОВАНI СОРТИ ПШЕНИЦІ

Abstract

Pseudomonas syringae, the causal agent of basal bacteriosis of wheat, is the most dangerous wheat pathogen in Ukraine. The phytopathogen affects all parts of plants and seeds, and may be the cause of their low germination. It also causes empty-head leading to crop losses and quality decrease. P syringiae survives on host plant residues, in soil and on seed. Seed infestation can play an important role in disease epidemiology. An important component of the outer membrane and the virulence factor of phytopathogenic bacteria of the genus Pseudomonas is lipopolysaccharide (LPS), which participates in pathogenesis processes, and is responsible for toxigenicity and immunogenicity of causal agents. The strategic importance of wheat in the agrarian market of Ukraine actualizes the research into the varieties resistant to basal bacteriosis. The study aims to determine the effects of phytopathogenic bacteria Pseudomonas syringae pv. coronafaciens and P. syrіngae pv. atrofaciens, as well as their LPS on seeds of different wheat varieties. Bacterial strains were obtained from the collection of live cultures at the department of phytopathogenic bacteria of D. K. Zabolotny Institute of Microbiology and Virology of the NASU. To conduct the experiment a suspension of living cells of the pathogen with a concentration of 109 CFU / ml and LPS solution at the concentration of 5 mg/ml was used. Exposure time was 24 h. The seed germination and the length of the main root of the sprout were determined after 4 days of germination period. Phytotoxic effect of P. syrіngae cells and their LPS was investigated using two varieties of winter wheat (Discus and Huculus) and spring wheat variety of Grenny. Introduced in Ukraine wheat varieties of foreign breeding Discus, Hukulus and Grenny were characterized by moderate sensitivity to phytopathogenic bacteria P. syrinae pv. coronafaciens and P. syrіngae pv. atrofaciens, as well as to their LPS. The most resistant to the phytopathogenic effect of P. syrіngae pathovars were the grains of the variety of winter wheat Discus. Live bacterial suspensions exerted a more pronounced phytotoxic effect, compared to their LPS, towards wheat grains of winter varieties and less pronounced than LPS - towards grain of spring wheat variety.