Biological Control of <i>Erwinia carotovora</i> ssp. <i>carotovora</i> by <i>Streptomyces</i> Species

Abstract

Ten isolates of Erwinia carotovora ssp. carotovora (Ecc) were isolated from infected potato tubers of Picasso, Sante, and Nevskiy varieties collected from different regions in Kyrgyzstan. Isolates were identified as Erwinia carotovora ssp. carotovora (Ecc) by standard bacteriological techniques and pathogenicity tests on tubers and also by PCR analyses. Tests on the pathogenicity of E. carotovora ssp. carotovora (Ecc) strains to host plants by artificial inoculation have shown a high sensibility of the Picasso variety. As a result, five isolates were chosen, three isolates (EcPo1, EcPo2, and Eco3) were highly pathogenic, while two isolates (Eco4 and Eco5) were weakly pathogenic. The antagonistic bacteria, Streptomyces diastatochromogenes strain sk-6, and Streptomyces graminearuss strain sk-2, have a highly significant effect on soft rot bacteria isolates (Ecc), more than the other tested antagonistic organisms in vitro screening biotests. The Streptomyces diastatochromogenes sk-6 was selected for the control assay of storage potatoes against the most common soft rot bacterial strain in Kyrgyzstan, Erwinia carotovora sp. carotovora EcPo2. The pretreatment of potato tubers with antagonistic bacteria successfully prevented the initial infection multiplication of soft rot bacteria and reduced soft rot disease of potatoes in storage. These results justify selection of the dose 10 6 cells/ml of bacteria Streptomyces diastatochromogenes sk-6 for use in powdering the infected or non-infected potato tubers to suppress the development soft rot during storage. Streptomyces diastatochromogenes sk-6 as a biological disinfectant could destroy surface and internal infections, protect the tubers from the growth of phytopathogenic bacteria in the early period of their reproduction, and improve the overwintering of winter crops.

Molecular Detection of the Causative Agent of Soft Rot (Pectobacterium carotovorum subsp carotovorum) in Banana (Musa sp.)

“…Whereas, maximum time taken for complete rotting of carrot was 5 and 7 days by Ipp 6 Igp 9, and Ien 11 , (Table 3). Rotting in carrot was slow and complete rotting was observed after 14 days after inoculation (Schillingford, 1974;Doolotkeldieva et al, 2016).…”

Antibacterial and antioxidant activities of Agaricus bisporus (J.E. Lange) imbach from Pakistan

“…These bacteria cause a number of serious plant diseases e.g., canker, necrotic spots, bacterial wilt, rot diseases and lesions in number of crop plants e.g., tomato, pepper, egg plant and citrus. These bacteria have been difficult to control by synthetic pesticides (Doolotkeldieva et al 2016). So, the present study was undertaken to evaluate bioactivities of constituents of A. bisporus partitioned through organic solvents like n-hexane, chloroform and ethyl acetate.…”

Isolation and efficacy of two bacterial strains antagonists of Erwinia amylovora and Pectobacterium carotovorum

“…These strains will be old, so its effect will slow down, suggesting that there were other mechanisms that interfered in the biocontrol like competition for iron traces through siderophore production or the ability of some bacterial isolates to activate defense systems in the host plant (Ait Bahadou et al 2018). Doolotkeldieva et al (2016) indicated that the presence or the absence of the disease and its degree was closely related to the concentration of the antagonist. If the concentration decreased, there will be the onset of the disease with an increasing degree.…”

“…From literature, fungi and bacteria antibiotics production, phytohormones release (auxins, gibberellins, cytokinins, and ethylene) from Streptomyces diastatochromogenes sk-6, S. graminearus strains, and Trichoderma lignorum, can decrease the virulence of P. carotovorum strain, with a degree differed from one antagonist strain to another, or in dose strain-dependent manner (Doolotkeldieva et al 2016).…”