Effect of PGPR bacteria on growth and content of photosynthetic pigments in the leaves of tomato plants

The dry biomass of plants and the content of pigments in the leaves of tomato cultivar Gruntovy Gribovskiy 1180 were analyzed 30 days after inoculation with growth-stimulating bacterial strains Pseudomonas sp. 2.4.1 and Stenotrophomonas sp. 2.13. It was revealed that the Pseudomonas sp. 2.4.1 strain stimulated the accumulation of plant biomass more efficiently than Stenotrophomonas sp. 2.13, which positively correlated with an increase in the content of chlorophyll and carotenoids in tomato leaves. Thus, the content of pigments in plants can serve as a marker of the effectiveness of associative symbiosis between tomato plants and various microorganisms.

FUNCTIONAL GROUPS OF BIFIDOFLORA OF INTESTINAL MICROBIOTA IN ASSOCIATIVE SYMBIOSIS OF HUMAN

Aim. Aim of the research is the identification of functional groups of human gut bifidoflora based on analysis of the spectrum of metabolites features, proteome, bioprofile, immunoregulatory properties and the ability to differentiate «self/non-self» among the associative microbiota. Materials and methods. The materials are 260 strains ofbifidobacteria isolated from 122 intestinal microsymbiocenoses. Experimental studies were carried out using bacteriological, chromatographic and immunological methods. Statistical processing of material is carried out by means of the package Statistica 10.0 using of k-cluster analysis and discriminant method. Results. As a result ofthe work, 3 clusters containing strains of various types of bifidobacteria were identified. The first cluster was represented by B. bifidum and was characterized by the antipeptide activity of the strains with respect to FNO-a and INF-y, IL-10. In the second cluster of the B. longum culture predominated, where the parameters of the backbone factor of microsymbiocenosis, the ability to microbial recognition, antagonistic activity and production of acetic acid were significant. In the third cluster the species composition of bifidobacteria was diverse and products of butyric, caproic acids and their isoforms were the informative tests. Conclusion. The key function of bifido-flora in the regulation of the homeostasis of the intestinal biotope is realized by the formation of functional clusters, among which the first group participates in the formation of the cytokine balance, the second group is responsible for the discrimination of associative microbiota and direct protection of the biotope from pathogens, and the third is necessary to maintain the barrier metabolic function of enterocytes in the human large intestine.

THE INFLUENCE OF TRIMAN-1 ON ASSOCIATIVE NITROGEN FIXATION AND NITROGEN FIXING MICROORGANISMS IN BARLEY ROOT ZONE

The influence of plant growth regulator triman-1 on nitrogen fixing bacteria and nitrogen fixation process in barley root zone was studied in the laboratory and field conditions. It was shown that triman- 1 enhances associative nitrogen fixation activity when mineral nitrogen fertilizers (N30) was used. The use of triman-1 increases efficiency of associative symbiosis more effectively with the use of carboammonium salts rather than with ammonium nitrate.

Associative symbiosis of Azospirillum lipoferum with dicotyledonous succulent plants of the Indian desert

The roots of several dicotyledonous xerophytic plants exhibited nitrogenase activity. Azospirillum lipoferum was isolated from the roots of these plants including several species of Opuntia having crassulacean acid metabolism. These isolates showed high rates of acetylene reduction; maximum nitrogenase activity was observed with the isolate from Opuntia vulgaris. Organic acids rather than sugars were preferred as carbon source for two selected isolates studied. However, no activity was detected with formic, oxalic, or lactic acid. Inorganic nitrogen sources caused significant reduction in nitrogenase activity, while organic sources such as amino acids and proteins either stimulated or did not significantly inhibit the activity. However, urea completely inhibited formation of nitrogenase activity. Growth measured as optical density was enhanced with all the nitrogen sources except potassium nitrite.