StatusThe thesis was presented on the 28 June, 2016
Approved by NCAA on the 6 October, 2016
Abstract– 2.25 Mb / in romanian
5.08 Mb /
Thesis for the degree of Doctor in Biological Sciences, Chisinau, 2016, consists of the introduction, four chapters, the main conclusions and recommendations, bibliography of 240 sources. The work is presented on 109 pages of the main text; it contains 9 tables, 35 figures and 2 supplements. The results within the dissertation were published in 12 scientific papers.
Domain of research: plant protection
Aim of research: To determine biological properties of bacteria E. amylovora and bacteriophages E. amylovora and to study the possibility of the E. amylovora bacteriophages application in the fire blight control.
Objectives: isolation, identification and pathogenicity estimation of the virulent bacteria E. amylovora (Burrill) Winslow et al.; isolation and identification of the virulent bacteria E. amylovora bacteriophages; determination of the E. amylovora bacteriophages growth particularities under the artificial and natural conditions; determination of the E. amylovora bacteriophages biological effectiveness in the fire blight control under the natural conditions.
Scientific novelty and originality. Bacteriophages, active against fire blight pathogen bacteria E. аmylovora were isolated from Rosaceae in the Republic of Moldova. The isolated bacteriophages were identified and characterized as members of Myoviridae и Siphoviridae viruses’ families. They are able to infect bacterial host cells independently of the exopolysaccharide layer thickness. The seasonal dynamics of the bacteriophages concentration in the host plants under the artificial and natural conditions is determined. The effectiveness of the bacteriophages to control bacteria E. аmylovora growth is determined in the laboratory experiments. The ability of some isolates of bacteriophages to reduce the disease rate of the fruit seedlings under the natural conditions is determined.
The important scientific problem solved in the respective domain consists in the scientific substantiation of the isolated, identified and characterized E. аmylovora bacteriophages capacity to lyze pathogen, which lead to elaboration of the technological elements of the active phage biomass production for fire blight control and allowed to determine phages biological effectiveness against fire blight in the laboratory and field conditions.
The theoretical significance. The results of the investigations, which have been carried out, are the contribution in the study of the theoretical background of the interactions between fire blight pathogen bacteria E. amylovora and bacteriophages E. amylovora in the tissues of the hosts’ plants under the artificial and natural conditions. The practical significance of the work. The biological effectiveness of the E. amylovora bacteriophages in the fire blight control has been determined. This allows to consider bacteriophages as a possible tool for fire blight control.
Implementation of scientific results: The isolated bacteriophages were tested in the fire blight control in the apple orchard of the enterprise “AgroBrio”, comuna Bacioi, Ialoveni dictrict. The obtained results of the bio ecological features of the E. amylovora bacteriophages investigation were used for the virology course elaboration at the State University of the Republic of Moldova.