Tsygankova V. Increase of plant resistance to phytopathogenic organisms through inducing of RNA-interference process with use of polycomponent growth regulators and genetic-ingeneering methods

The results of investigations concerning possibility of increasing of plant resistance to phytopathogenic organisms using polycomponent growth regulators with natural origin as well as genetic-ingeneering methods, and also genetic and epigenetic mechanisms of improvement of these signs at plants are found out. Using molecular-biological methods it is set that accelerating of germination of haricot bean seeds action of growth regulators Ivin and Radostim is mediated through activation by them of biosynthesis of mRNA, rRNA and proteins. By Dot-blot hybridization method the essential difference in homology degree (to 22 %) between mRNA populations from embryo axis cells of haricot bean seeds treated and untreated with regulators Emistim and Avercom it is set. Influence of growth regulators Emistim C, Radostim, Agrostimulin, Zeastimulin, Biolan is found on increase of protein biosynthesis in cells of 5-day sprouts of haricot bean, pea, soya, barley, wheat and corn plants, and also in cell free system from wheat sprouts on the template poly(A)+RNA from cells of these sprouts. The increase of resistance of some crops to wreckers and pathogenic organisms is established at pre-sowing treatment of seeds and crop spraying by growth regulators in field and greenhouse experiments: Regoplant (up to 98 %), Stimpo (up to 89 %) and Radostim (up to 74 %) which promoted preservation of a crop more than on 80 % comparatively with control. By Dot-blotting mRNA with si/miRNA and study of silencing activity si/miRNA in cell-free system of protein synthesis it is shown the first that resistance of sugar beet plants to nematodes H. schachtii and M. incognita it is reached by stimulation by growth regulators of synthesis in plant cells of antinematodic si/miRNA. The considerable differences (up to 6-23 %) in homology degree between mRNA of control and si/miRNA of experimental wheat, cucumbers and potato plants, infected by pathogenic micromycete F. oxysporum and parasitic nematodes M. іncognita and D. destructor and treated by growth regulator Avercom and its derivatives is set; in the cell-free system from wheat sprouts the influence of these regulators on increase of silencing activity of si/miRNA is revealed. Using mediated by A. tumefaciens genetic transformation by constructed vector of dsRNA expression, specific to conservative region of 8Н07 gene of root parasitic nematode H. schachtii, the rape plants with the increased resistance to this nematode are obtained.