Growth-Stimulating Activity Of Copper-Containing Nanocomposites In Natural Polymer Matrices
The biological activity of two chemically synthesized nanocomposites (NC) of copper(I) oxide (Cu<sub>2</sub>О) based on natural polymer matrices of arabinogalactan (AG) and starch (ST) was studied in order to develop a new growth stimulator for plants. The results of experiments on studying the effect of NC on the growth rates (length and weight of stems, biomass of roots) of soybean seedlings and the content of diene conjugates (DC) in the tissues of their stems, as well as on the growth of stems and the number of leaves, the biomass of the aerial parts of plants and roots of the potato variety “Lugovskoy” in vitro, infected with the causative agent of ring rot - the bacterium <i>Clavibacter sepedonicus</i> and controls, and the content of DC in the tissues of their leaves and roots. The results of the study of the growth-stimulating effect on plants of Cu<sub>2</sub>O/AG and Cu<sub>2</sub>O/ST showed that only NC Cu<sub>2</sub>O/AG has this effect. Microscopy of potato root tissues using fluorescent dyes showed that when processing potatoes with NC Cu<sub>2</sub>О/AG, its roots do not die, the cells remain viable. The effect of the nanocomposite copper oxide-starch Cu<sub>2</sub>O/ST on soybean seedlings was expressed in a decrease in the growth and weight of the stems, a neutral effect on the length and weight of the roots, and an increase in the content of DC in their tissues. The same kind of effect was also registered on microclonal potato plants. On the contrary, the nanocomposite of copper oxide - arabinogalactan Cu2O/AG stimulated an increase in the length and weight of the stems of soybean seedlings, as well as the biomass of roots and significantly reduced the level of DC in their tissues. A negative effect on the growth and development of potatoes, as well as the status of the redox system of potatoes, both infected with the Cms pathogen and free from infection, was not established: the level of DC in its tissues did not increase. The experiments performed indicate the prospects of using the nanocomposite copper oxide - arabinogalactan Cu<sub>2</sub>O/AG of arabinogalactan as a means for combating bacterial pathogens of agricultural crops.