Isolation of <italic>Dickeya dadantii</italic> strains from potato disease and biocontrol by their bacteriophages
Soleimani-Delfan, AbbasEtemadifar, ZahraEmtiazi, GitiBouzari, Majid
<p>One of the most economically important bacterial pathogens of plants and plant products is <italic>Dickeya dadantii</italic>. This bacterium causes soft rot disease in tubers and other parts of the potato and other plants of the <italic>Solanaceae</italic> family. The application of restricted host range bacteriophages as biocontrol agents has recently gained widespread interest. This study purposed to isolate the infectious agent of the potato and evaluate its biocontrol by bacteriophages. Two phytopathogenic strains were isolated from infected potatoes, identified based on biochemical and 16S rRNA gene sequencing, and submitted to GenBank as <italic>D. dadantii</italic> strain pis3 (accession no. HQ423668) and <italic>D. dadantii</italic> strain sip4 (accession no. HQ423669). Their bacteriophages were isolated from Caspian Sea water by enriching the water filtrate with <italic>D. dadantii</italic> strains as hosts using spot or overlay methods. On the basis of morphotypes, the isolated bacteriophages were identified as members of the <italic>Myoviridae</italic> and <italic>Siphoviridae</italic> families and could inhibit the growth of antibiotic resistant <italic>D. dadantii</italic> strains in culture medium. Moreover, in <italic>Dickeya</italic> infected plants treated with bacteriophage, no disease progression was detected. No significant difference was seen between phage-treated and control plants. Thus, isolated bacteriophages can be suggested for the biocontrol of plant disease caused by <italic>Dickeya</italic> strains.</p>.(AU)
Texto completo