[ANTINEMATICIDAL ACTIVITY OF METABOLITES PRODUCED BY SOIL STREPTOMYCETE].

GOAL: To study in vitro the antinematicide activity of soil streptomycetes metabolite and bioformulations based on them against root-knot, cyst and leaf nematodes of species. METHODS: Action of streptomycetes metabolites and their bioformulations were determined in vitro against larvae at two age of root-knot nematode M incognita (Kofoid & White, 1919) Chitwood 1949 and sugar beet cyst nematode H. schachtii A. Schmidt 1871, and leaf nematodes ofAphlenchoides genus by cultivation them in solutions of biomass ethanol extracts separate individual components metabolites and bioformulations during 24 hours. Nematicide and nematistatic effects of the substances were evaluated by the change in the motility activity of the nematodes. RESULTS: Soil streptomycetes S. violaceus IMV Ac-5027, S. averinitilis IMV Ac-5015 and metabolite bioformulations based on them (Violar, Aver- com and Avercom-nova, respectively) showed significant nematicidal activity against plant pathogenic nematodes M incognita and H. schachtii. The biomass extracts of S. avermiti- lis IMV Ac-5015 and S. violaceus IMV Ac-5027 caused 100 % death of nematodes, and S. netropsis IMV Ac-5025 caused only 75 % mortality during 24 hours of action. Using an antibiotic complex from S. violaceus IMV Ac-5027 was divided on six fractions that were different from the avermectin complex. Purified fractions of individual antibiotic complex of S. violaceus IMV Ac-5 027 have a negative impact against the root-knot nematode M incognita. The highest nematicidal activity showed fractions #4 and #5 since their efficiency was over 90 % after a 0.5 hours of action. Nematicidal efficiency of fractions ## 1, 2, 3 and 6 remained between 72.6-86.2 % during 24 hours of action. Fractions 4 and 5 showed high nematicidal effectiveness against leaf nematodes of Aphelenchoides genus where 90-95 % level of helminthes death was observed after 4 hours of action. Among created complex metabolite bioformulations Avercom-nova was the most effective which caused 100 % mortality of nematodes M incognita and H. schachtii after 24 hours of action. Bioformu- lation Violar caused 96.6-96.8 and 95.2-97.0 % of death of nematodes M incognita and H. schachtii, after 24 hours of action. Phytovit based on S. netropsis IMV Ac-5025 showed low nematicide activity against of nematodes, which did not exceed 15.2-18.4 % of their death after 24 hour of action. Bioformulations based on streptomycetes metabolites did not inferior to chemical insecticide Konfidor Maxi, which caused the death of 93.3-94.6 % nematodes at doses recommended by the manufacturer. CONCLUSION: Soil streptomycetes S. violaceus IV Ac-5027 and S. avermitilis IMV Ac-5015 are promising producers for creation of bioformulations with nematicidal activity against plant-parasitic nematode of M incoenita and H. schachtii.

[Identification and Antagonistic Properties of the Soil Streptomycete Streptomyces sp. 100].

Aim: Determination of the taxonomic status of the soil streptomycete Streptomyces sp. 100 and study of its antagonistic properties against phytopathogenic and opportunistic human microorganisms. Methods: For the identification of the strain a set of conventional methods morphological and cultural, physiological and biochemical characteristics of the producer, as well as molecular genetic analysis of 16S rRNA gene were used. Streptomycete was cultivated on agar nutrient and liquid soy medium until the stationary phase of growth. The antagonistic activity of the strain was studied by agar diffusion method. Results: The study of morphological and cultural properties showed that Streptomyces sp. 100 formed the colonies with irregular edges protruding from the depressed center, straight sporophores were short, gathered in whorls; spores were oval, smooth shell dispute. Growing on agar medium (pH 6.8-7.4, temperature 28 °C, microaerophilic conditions) this strain formed mycelium of various colors: the air white, white-yellow, white-brown or substrate tan, cream and yellow, creamy carmine, yellow-brown. A soluble pigment was yellow and yellow-brown, while melanoid pigment was not detected. The morphological, cultural, physiological, biochemical and molecular genetic characteristics of the soil streptomycete let to identify it as Streptomyces netropsis (Finlay et al., 1951) IMV Ac-5025 (UCM Ac-2186) that is an active antagonist IMV Ac-5025 against plant pathogens. Growing on a surface of agaric nutrient media it inhibits phytopathogenic bacteria (Xanthomonas axonopodis pv. glycines 8609, Pseudomonas savastanoi pv. glycinea 8571, P. syringae pv. coronafaciens 9030) and fungi (Alternaria alternata 16814, Fusarium оxysporum 54201) zone of growth inhibition were 20 - 32 mm and 16 - 30 mm respectively. The supernatant of culture medium and the ethanol extract of biomass inhibited the growth of pathogenic bacteria and fungi. The most sensitive to action of a supernatant of cultural liquid were P. syringae pv. atrofaciens 7886 and Clavibacter michiganensis ssp. michiganensis 102, growth inhibition zones - 42 and 30 mm respectively. It should be noted that in the majority of cases the supernatant of cultural liquid suppressed growth of phytopathogenic bacteria in comparison with biomass extract more actively. At the same time only biomass extract inhibited the growth of P. syringae pv. coronafaciens 9060, P. corrugatа 9070, X. anoxopodis pv. glycines 9075, X. anoxopodis pv. glycines 8609 and Pantoea agglomerans 8490. Tolerant to metabolites of S. netropsis IMV Ac-5025 were P. syringae pv. atrofaciens 8291 and X. visicatoriae 7790. The extract of biomass S. netropsis IMV Ac-5025 inhibited growth of all studied strains of phytopathogenic fungi (A. alternata 16814, A. culmorum 00790, F. оxysporum 54201, F. tricinetum 00795, F. oxysporum n.33, Cladosporium herbarum 16863, Cochliobolus spicifas 16860, Nigrospora oryzae 16864). The supernatant of the cultural liquid also showed the oppressing action on fungi, except for Cladosporium herbarum 16863 and Cochliobolus spicifas 16860. The strain was almost ineffective against opportunistic human microorganisms (Escherichia coli ATCC 25922, Bacillus pumilus NCTC 8241, Staphylococcus aureus FDA 209P et al.). Conclusions: The lack of action of Streptomyces netropsis IMV Ac-5025 on the opportunistic human microorganisms and the active antagonism of phytopathogens, both, define potential its application for plant protection.