Antagonistic Activity of Azotobаcter vinelandii IMV B-7076 against Phytopathogenic Microorganisms

Abstract

Bacteria of the genus Azotobacter are known for their ability to stimulate plant growth and development. Azotobacter vinelandii IMV B-7076 strain was isolated from Zhytomyr region soil of Ukraine. It is one of the components of the "Azogran" complex bacterial preparation for plant growing. It has been established that A. vinelandii IMV B-7076 synthesizes biologically active substances that promote plant development. At the same time, the antagonistic activity of A. vinelandii IMV B-7076 against phytopathogens has not yet been studied, so this became the aim of this work. Methods. The antagonistic activity of A. vinelandii IMV B-7076 was determined by agar well diffusion and agar blocks methods. Results. It was shown that A. vinelandii IMV B-7076 had antagonistic activity against some phytopathogenic fungi. In particular, the diameter of growth inhibition zones of Alternaria alternata 16861, Fusarium avenaceum 50720, Fusarium verticillioides 50463, Fusarium lactis 50719, Fusarium oxysporum 54201, Fusarium poae 50704 was 14-37 mm, Bipolaris sorokiniana 16868 and Fusarium solani – 11-13 mm. Fusarium culmorum 50716 and Fusarium graminearum 50662 were not sensitive to A. vinelandii IMV B-7076 metabolites. Notably, the antagonistic effect was demonstrated in mycelial growth and spore formation inhibition, in fungal mycelium discoloration. It was also demonstrated that A. vinelandii IMV B-7076 did not show antagonistic activity against phytopathogenic bacteria Agrobacterium tumefaciens 8628, Pectobacterium carotovorum subsp. carotovorum 8982, Pseudomonas fluorescens 8573, Pseudomonas syringae pv. syringae 8511, Clavibacter michiganensis subsp. michiganensis 13a, Xanthomonas campestris pv. campestris 8003b. Conclusions. Studied A. vinelandii IMV B-7076 strain is characterized by antagonistic activity against phytopathogenic fungi and does not have antibacterial properties against phytopathogenic bacteria. The antifungal activity of A. vinelandii IMV B-7076, as a component of "Azogran", will be useful for this bacterial preparation application in plant growing.

Influence of the Complex Bacterial Preparation Azogran on Some Physiological-Biochemical Properties and Productivity of Potato Plants Infected by the Potato Virus X

“…It was previously established that the strain B. subtilis IMV B-7023, which is part of the Azogran preparation, is characterized by a wide spectrum of antagonistic activity against phytopathogenic bacteria and micromycetes [10]. A. vinelandii IMV B-7076 also has the ability to suppress the spread of phytopathogenic micromycetes [11]. Previous studies have estab-potato virus X, only to a lesser extent: in the Diva variety, the yield was 16.3% higher compared to the control (controlplants not infected by the virus), and in the Spokusa variety it was higher by 22.59%.…”