Morphological and physiological properties of lupine nodule bacteria (Bradyrhizobium lupini) when grown on a typical urban soil.

In the conducted studies, the moorphological and physiological properties of nodule bacteria of lupine were studied. Lupine plants were grown under the conditions of a microfield experiment on a typical medium loamy urban soil. In the study, a pure culture of Bradyrhizobium lupini was isolated. Then, the morphological properties of nodule bacteria cells and the chemical composition of cell membranes of nodule bacteria were determined. The acid resistance and physiological properties of lupine nodule bacteria were also determined, as well as the ratio of Bradyrhizobium lupini to antibiotics. All studies were carried out according to generally accepted methods. The results of the research showed that during the cultivation of lupine on a typical urban soil, nodule bacteria Bradyrhizobium lupini were isolated, which can be characterized as gram-negative, non-spore-forming rods that do not exhibit amylolytic activity. It was revealed that the rhizobia of nodule bacteria are not acid-resistant. Nodule bacteria turned out to be the least resistant to polymyxin, then to levomycetin, and Bradyrhizobium lupini showed the greatest resistance to tetracycline.

Comparative study of symbiotic activity of legumes when using Risotorphin and Epin-extra.

In a vegetation experiment with soybean plants of the Svapa and Mageva varieties and in a field experiment with bean plants of the Geliada and Shokoladnitsa varieties, we studied the effect of pre-sowing treatment of the seeds of these plants with Rizotorfin and Epin-extra on the nitrogenase activity of the nodules of these plants and their ultrastructure. Analysis of the ultrastructure of the nodule tissue of beans and soybeans was carried out in the flowering phase. It was found that the highest indices of the mass and number of nodules and the activity of nitrogenase in them were found in bean plants of the Heliada cultivar when the seeds were treated with Epin-extra against the background of inoculation with Rizotorfin, where the largest area of symbiosomes, volutin and their number was noted in the nodules. Beans of the Shokoladnitsa variety showed the protective effect of Rizotorfin. In the nodules of soybean plants of the Svapa variety, the seeds of which were treated with Epin-extra against the background of inoculation with Rizotorfin, the presence of a large number of symbiosomes, bacteroids, volutin inclusions with a larger area and a minimum number of inclusions of poly-ß-hydroxybutyric acid (PHB) was noted, and the highest indicators of symbiotic activity. Soybean plants of the Mageva variety showed the protective effect of Rizotorfin. The efficiency of the symbiotic system was determined by the number and weight of nodules and the activity of the nitrogenase enzyme.