Aim. Obtaining in vitro new lines of potato (Solanum tuberosum L.) cultivar Vernissage with genetically mediated resistance to the parasitic nematode H. schachtii on nutrient MS media with microbial bioregulators. Methods. In vitro conditions the process of organogenesis of potato plants on nutrient MS media containing microbial bioregulators used at concentrations 25-100 μl/l in combination with phytohormones 2 mg/l BAP and 0,1 mg/l NAA was investigated. Using dot blotting method the degree of hybridization between cytoplasmic si/miRNA isolated from cells of potato plants-regenerants, grown on the artificial invasive background, and nematode mRNA was studied. In the wheat seedlings cell-free system in vitro the silencing activity of si/miRNA isolated from cells of potato plants-regenerants on the template of nematode mRNA was investigated. Results. The experiments conducted in vitro conditions showed that the addition of microbial bioregulators at concentrations 25-100 μl/l in combination with phytohormones 2 mg/l BAP and 0,1 mg/l NAA into MS media increased the efficiency of regeneration of potato shoots to 43–47 % as compared with similar indices obtained on control MS media. The increase of the degree of hybridization to 19-38 % between cytoplasmic mRNA isolated from cells of nematode H. schachtii and si/miRNA isolated from cells of experimental potato plants-regenerants grown in vitro conditions on nutrient media containing bioregulators on the artificial invasive background was shown. Conclusions. Using microbial bioregulators in vitro conditions as components of nutrient MS medium increases potato shoot regeneration efficiency and enhances RNAi-mediated resistance of plants-regenerants to parasitic nematode H. schachtii.
Keywords: microbial bioregulators, potato organogenesis in vitro, potato resistance to nematode Heterodera schachtii, RNA interference.