Impact of lipopolysaccharides from rhizospheric bacteria on the growth of potato microplants under in vitro conditions

The surface of gram-negative bacteria is formed mainly by lipopolysaccharide molecules, which are involved in the interaction of microorganisms with various environmental objects, including plants. In this work, we studied the effect of lipopolysaccharides from six bacterial strains of different taxonomic groups on the growth of potato microplants cultivar Kondor under in vitro conditions. It was shown that the greatest positive effect on such parameters as shoot length, total root length, dry weight of shoots and roots was exerted by lipopolysaccharides of the strains Ochrobactrum quorumnocens T1Kr02 and Azospirillum thiophilum BV-S, the O-polysaccharides of which consist entirely or mostly degree from 6-deoxyhexose residues (fucose and rhamnose). The results can be used to more quickly select effective lipopolysaccharides and the bacteria that produce them as growth promoters for microplant cultivation under in vitro conditions.