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Phenotypic properties (growth characteristics, utilization of carbon and nitrogen sources, and intrinsic antibiotic resistance) of 53 Rhizobium strains isolated from root nodules of the temperate-zone legumes Astragalus spp. (29 strains), Oxytropis campanuhta (7 strains), Hedysarum alpinum (7 strains), Ononis awensis (3 strains), Glycyrrhiza spp. (4 strains), and Coronilh varia (3 strains) were compared with those of other Rhizobium, Bradyrhizobium, and Agrobacterium strains. The final matrix, containing 83 strains and 56 nonsymbiotic features, was used for computer cluster analysis. The dendrogram showed that the new strains of temperate-zone rhizobia formed a cluster separate from both Rhizobium and Bradyrhizobium spp. Two large groups of temperate-zone rhizobia were revealed. Group 1 included rhizobial strains originating from different geographical regions with a temperate climate, while group 2 included strains from the same geographical origin, South Siberia. The 'strains of recognized Rhizobium species were clustered, in general, with each other as expected from phylogenetic relatedness.Root nodule bacteria of the genera Rhizobium and Bradyrhizobium are a common microflora of temperate soils. These bacteria may interact with the roots of leguminous plants, inducing the formation of nodules in which the fixation of atmospheric nitrogen occurs. These bacteria are commonly used in agriculture for improvement of plant growth. The specificity of the interaction between rhizobia and legumes depends on many factors coded for by the host cultivar and bacterial genomes;. The main properties of a bacterial isolate can be described by its taxonomical position in relation to other strains. There are several Rhizobium species recognized at this time (10, 1.3, 24), and knowledge of rhizobial evolution and phylogeny obtained in recent studies allows the proposal of new rhizobial taxa (3,16,25). However, the current systematic description of the genus Rhizobium does not include many of the root nodule isolates from legumes of tropical (22, 37), arctic (21), and temperate (5, 12, 17) regions.The host plant specificities and phage sensitivities of Rhizobium strains from temperate-zone legume root nodules formed on Astragalus, Hedysamm, Glycywhiza, and Ononis plants were recently described (17). It was shown that these strains constitute a cross-inoculation group related to Rhizobium loti. The aim of the present work was to determine the cultural properties of these strains and to compare these properties with those of other Rhizobium species. MATERIALS AND METHODSBacterial strains. Bacterial strains used in this work are listed in Table 1. Bacteria were maintained on yeast extractmannitol (YEM) (29) agar slants at 4°C.Growth characteristics. The time necessary for full colony development on YEM agar (estimated here as a colony diameter of 2 mm) was determined. Bacterial growth on meat-peptone agar and reactions with litmus milk were determined as described earlier (11). The ability of strains to grow in the presence of 0,1...

Twenty-five Rhizobium strains were isolated from root nodules of Astragalus spp. (lo), Hedysarum alpinum (7), Glycyrrhiza pallidiflora (3) and Ononis arvensis (5). The sensitivity of these strains to bacteriophages of Rhizobium loti, R. meliloti, R. galegae and R. leguminosarum was studied. Phages specific to R. loti strains were shown to induce the phage lysis of several Astragalus, Hedysarum and Ononis rhizobia. Ten R. loti strains tested for nodulation abilities on the plant hosts under investigation were able to develop nitrogen-fixing nodules on the Ononis arvensis roots. On the other hand, rhizobia from Ononis and Glycyrrhiza could form an effective symbiosis with Lotus corniculatus plants, so these bacteria are considered to belong to the Rhizobium loti taxon. Bacterial strains isolated from Astragalus and Hedysarum were observed to cross-nodulate their plant hosts as well as Oxytropis campestris, Glycyrrhiza uralensis and Ononis arvensis plants, whereas they could not nodulate Lotus plants. It is concluded that these Rhizobium strains comprise a cross-inoculation group related to Rhizobium loti.

Thirty microbial phylotypes of microorganisms were found in the gastrointestinal tract of chicken belonging to the Hajseks White breed, and 38 phylotypes were found in the gastrointestinal tract of chicken belonging to the Hajseks Brown breed. The microbiome of the gastrointestinal tract of the chicken embryos of the Hajseks White breed was dominated by the typical representatives of avian intestinal microflora--bacteria of the family Enterobacteriaceae (47.3%), orders Actinomycetales (13.6%) and Bifidobacteriales (20.6%), and the family Lachnospiraceae (1.1%). The microbiome of the gastrointestinal tract of the chicken embryos of the Hajseks Brown breed was dominated by the pathogenic bacteria of the order Rickettsiales (94.8%). The metagenome of gastrointestinal tract of both breeds also contained a small number of genes of unidentified bacteria.

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A b s t r a c tMicroorganisms which inhabit gut play great role in providing with nutrients, antibiotics, hormones and vitamins necessary for poultry health and performance. Therefore study of gut microbiome changes during ontogenesis seems to be essential. The structure of gut microflora in poultry embryos is of particular interest and debated because of very few publications on the problem. Despite embryo intestine is commonly considered sterile there are several reports on gut colonization by microorganisms in embryos during ontogenesis. Using T-RFLP (Terminal Restriction Fragment Length Polymorphism) analysis to generate a fingerprint of a microbial community we compared gut flora in chick embryos on days 6 and 17 to those in 26-day, 150-day and 300-day old Hisex White layers. Unlike accepted view, a high biodiversity was seen in embryo gut with Enterobacteriaceae (Escherichia coli mainly) predominated. Clostridia, Bacteroides, Negativicutes, Actinomycetales, Bifidocteriales were also found in contrast to earlier reports of their presence only in chicks at hatching and in adult poultry gut. Moreover, in the embryo gut we found the causal agents of dangerous animal disease, Burkholderia sp., Pseudomonas sp., Salmonella sp., Klebsiella sp. and Rickettsiales bacteria. Interestingly, the embryo gut biodiversity on day 6 was higher as compared to day 17 (75±2.75 phylotypes vs 30±1.20 phylotypes). In the layers aged 26, 150 and 300 days the diversity was much higher (over 175±8.12 phylotypes) as compared to embryos due to new members involved into gut bacterial community. Moreover, the poultry aged 300 days was lower both in the total diversity and in the percentage of unidentified microorganisms when compared to 26-day and 150-day old hens. In the adults, the predominating microbial taxa changed, in particular, Clostridia and Negativicutes became more abundant whereas Bacillales and Bifidobacteriales were depressed. Our findings indicate gut colonization by Lactobacilales and pathogenic Listeria sp., Pantoea sp., Enterobacter sp., Mycoplasma sp., Acinetobacter sp., Pasteurellaceae, Campylobacteraceae, Fusobacteria which occurred during ontogenesis. Thus the gut microbiome formation starts in embryo which is important for hatching and growing healthy poultry.

The composition of plant and silage microflora affects the fermentation processes in the silage and its final quality. To date, reports about studying fodder plants and silage microbiota by means of molecular genetic methods are few and limited to descriptions of composition and function of some groups of microorganisms. Moreover, the NGS (next generation sequencing) data on diversity of epiphytic microflora and silage microbiocoenosis are not still reported. We first used this approach in studying phyllosphere and silage microbiom, and reported it to be rather rich in composition and abundance that is in contrast with conventional understanding. At that, the pathogenic and non-culturable microbes were detected in the microbiota, including specific inhabitants of mammalian gastrointestinal tract. So using NGS we examined the structure and diversity of bacterial community of Dactylis glomerata L. harvested plants and the biomass ensilaged with chemical preservative AIV 2000 Plus (KEMIRA OYJ Inc., Finland) composed of mixture of formic, propionic and benzoic acids. Assays were carried out on days 3, 7, 14 and 30 of ensilaging. The results showed that the bacterial community of silage from D. glomerata sharply differed from the composition of foliage microorganisms and varied greatly in the course of successive changes which occurred during maturation of silage preserved by mixture of organic acids. The composition of plant microorganisms and silage were found to be very various in contrast with a traditional view. Among foliar microorganisms of D. glomerata there were mostly the bacteria of phylum Proteobacteria (94.1 %), and in the silage the bacteria of phylums Bacteroidetes and Firmicutes were main representatives (up to 59.5 % and 74.9 %, respectively). In taxonomic diversity of the order Lactobacillales, mainly involved in ensilaging, there were genera Lactobacillus (up to 39.6%), Enterococcus (up to 36.36 %), Lactococcus (up to 14.4 %), Pediococcus (to 1.45 %) and the family Leuconostocaceae (to 3.52 %). Interestingly, in the silage there were the bacteria of phylum Bacteroidetes, families Ruminococcaceae, Lachnospiraceae and Selenomonadales considered the common inhabitants of the mammals' gastrointestinal tract, and also the uncultured and pathogenic microorganisms. Particularly, these were 15 genera of family Enterobacteriaceae, including genera Klebsiella, Salmonella, Yersinia, etc., among which the dangerous mammalian pathogens are frequent. On days 3 and 7, the phylum Bacteroidetes prevailed (59.53 and 48.91 %, respectively). On days 14 and 30, the phylum Firmicutes was dominant (up to 74.85 %) with the facultative aerobic bacteria of order Lactobacillales mostly found (up to 74.76 %). Using NGS, a total of 70 genera were attributed in the plant phyloshere, and in the silage there were 84 genera on day 3, 96 genera on day 7, 51 genera on day 14, and 69 genera on day 30. Classical microbiology methods are not enough to detect these bacteria among silage microbiota.