Effect of Bacterial Strains with Different Ability to Synthesize Auxins and Cytokinins on the Growth and Water Relations of Wheat Plants

Abstract

The content of cytokinins, auxins, chlorophyll, transpiration, content and relative content of water, water and osmotic potentials, hydraulic conductivity, morphological parameters of durum wheat (Triticum durum Desf.) plants after the introduction into their rhizosphere of cytokinin-producing strains (Bacillus subtilis IB-22) or auxin-producing (Pseudomonas mandelii IB-Ki14) bacteria was evaluated. The experiments were carried out in laboratory conditions in vessels with agrochernozem at an optimal level of illumination. It was shown that the cytokinin-producing strain stimulated plant growth, accumulation of chlorophyll, and increased transpiration to a greater extent compared to plants treated with the auxin-producing strain. Plants under the influence of the B. subtilis IB-22 strain lost more water during transpiration, while there was no decrease in the level of water content and turgor. It is concluded that bacterial cytokinins affect the water metabolism of wheat plants by increasing hydraulic conductivity, and bacterial auxins - to a greater extent due to osmotic regulation. A more significant stimulation of plant growth by bacteria of the B. subtilis IB-22 strain is also explained by the ability of cytokinins to influence the chlorophyll content to a greater extent than auxins.