Symbiotic and physiological indicators of soybean inoculated of Bradyrhizobium japonicum single-strain in 7 days before sowing

Abstract

<p class="042abstractstekst">Results of investigation of soybean of the Almaz variety in inoculation with preparations based on nodule bacteria <em>Bradyrhizobium japonicum</em> (Kirchner, 1896), Jordan, 1982 B78, B157, D37, D87 are presented. Different periods of the soybean seeds inoculation were used - on the sowing day (control) and in 7 days before sowing (experimental variants). The differences between control and experimental plants in the formation and functioning of the symbiotic apparatus and its functional activity, depending on the period between from seed inoculation to sowing were analysed. It was determined that the number of root nodules in the control plants was higher. The mass of nodules at the stage of 3 true leaves exceeded the control by 1.5–2.0 times in plants inoculated in 7 days before sowing, and the intensity of nitrogen fixation by 1.7–6.6 times. At the budding-beginning of flowering stage, the mass and intensity of N<sub>2</sub> fixation by the nodules of control plants increased. As a result, the difference between the nitrogen fixing activity of control and experimental plants decreased significantly. Stimulating effect on aboveground mass of <em>Bradyrhizobium japonicum</em> strains with increased nitrogen fixing activity was noted. Optimal conditions for the formation and functioning of bean-rhizobial symbiosis were provided at the use of both of these terms of soybean inoculation. This reveals the possibility of effective application of early inoculation of soybean seeds with preparations based on nodule bacteria <em>Bradyrhizobium japonicum</em> active strains.</p>

Effect of Soybean Seed Inoculation with Symbiotic Bacteria

“…In addition, the latter authors demonstrated a strong correlation between nodule dry weight and pod dry weight. Vorobey et al (2022) reported that, on average, the number of nodules formed on a single soybean root after seed inoculation ranged from 14 to 45. Other study demonstrated that the weight of nodules on a single soybean Effect of Soybean Seed Inoculation with Symbiotic Bacteria root ranged from 0.22 to 0.24 g, depending on the experimental soil conditions .…”