Abstract
A significant part of the used pesticides does not reach the target organisms and, while remaining in the agrophytocenosis, influences all living organisms in it. Having a toxic and often mutagenic effect, pesticides induce morphological and physiological changes in the cells of microorganisms and are the cause of phenotypic heterogeneity of their populations. However, the effect of pesticides on phytopathogenic bacteria as non-target microorganisms remains out of the field of view for most researchers. However, the use of pesticides can lead to expansion of the diversity of existing phytopathogens and, as a consequence, complications of identification of the pathogens, loss of resistance by plants varieties, and increased harm from diseases caused by them. This study is focused on the effect of pesticides used in tomato plantations on the causative agent of bacterial speck of this crop—Pseudomonas syringae pv. tomato. The studies were carried out using the methods of classical microbiology. The mutagenic action of pesticides was recorded, taking into account the increase of the number of streptomycin resistance mutations in bacteria in the case of pesticide action. It is established that the fungicide aluminium phosethyl is characterised by a bacteriostatic effect on P. syringae pv. tomato. Deltamethrin insecticide does not affect the growth of P. syringae pv. tomato. However, there is an increase in the frequency of streptomycin resistance mutations in both studied strains of P. syringae pv. tomato after using deltamethrin. It is shown that the frequency of occurrence of R (rough colonies) forms of P. syringae pv. tomato IZ28 and IZ46 after using deltamethrin increased by 100 times when in comparison to the frequency of spontaneous morphological dissociation, or smooth-to-rough (S-R) mutation, of these bacteria. Therefore, aluminium phosethyl is characterised by moderate bacteriostatic action against P. syringae pv. tomato. Deltamethrin does not influence the growth of the pathogen of tomato speck but increases the frequency of formation of StrR mutants and R forms of phytopathogenic bacteria.
Highlights
Tomato is affected by a number of bacterial diseases, the harmfulness of which is determined by climatic conditions and the general condition of plants [1,2,3,4]
Deltamethrin insecticide does not affect the growth of P. syringae pv. tomato
To determine the toxic effect of pesticides on the pathogen of tomato bacterial speck, they were introduced into the liquid culture medium LB Broth, on which P. syringae pv. tomato strains were introduced into the liquid culture medium LB Broth, on which P. syringae pv. tomato strains were incubated for 48 h
Summary
Tomato is affected by a number of bacterial diseases, the harmfulness of which is determined by climatic conditions and the general condition of plants [1,2,3,4]. Regarding Ukraine, the causative agent of black rot Xanthomonas vesicatoria, the causative agent of bacterial speck Pseudomonas syringae pv. Tomato and bacterial canker pathogen Clavibacter michiganensis subsp. Michiganensis are economically significant [5]. Sci. 2020, 10, 3263 of the genetic and phenotypic diversity of existing pathogens and, as a consequence, complications with identification of the pathogen, loss of resistance by varieties, and increased harm from bacterial diseases. The use of pesticides is one of the factors that increases variability of phytopathogens [6,7,8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
