## 3 Results  
Interactions between Symbiotic Bacteria (Bradyrhizobium sp.) and Endophytes (Pseudomonas fluorescens or Bacillus subtilis)  
The analysis of interactions between the strains of bacteria of the _Bradyrhizobium_ genus isolated from the Nitragina preparation and the _Pseudomonas fluorescens_ or _Bacillus subtilis_ endophytes did not reveal any antagonistic interactions, as evidenced by the lack of brightening (halo) around the wells (Figure 1). There were similar results of the analysis of interactions between the strains of bacteria of the _Bradyrhizobium_ genus isolated from the Nitroiflora preparation and the _Pseudomonas fluorescens_ or _Bacillus subtilis_ endophytes (Table 1). Influence of Coinoculation on Weight of Belowground and Aboveground of Plants and Degree of Root Colonisation by Endophytic Bacteria--Laboratory Test  
The analyses showed that different variants of the inoculation of lupine plants significantly influenced the weight and length of their aboveground and belowground parts (Table 2). Both the inoculation (single inoculation) and coinoculation (simultaneous inoculation with symbiotic bacteria and endophytes) stimulated the growth of the aboveground and belowground parts of the plants, which were longer and heavier than the control plants. The length of the lupine stems ranged from 17.5 to 20.3 cm. The longest stem was found in variant nine, where the plants had been coinoculated with bacteria of the _Bradyrhizobium_ genus isolated from the Nitrolora preparation and the _Bacillus subtilis_ endophyte. The weight of the stems ranged from 1.88-2.84 g. Coinoculation also resulted in the heaviest weight of the stems. In variant seven, where the plants had been coinoculated with bacteria of the _Bradyrhizobium_ genus isolated from the Nitragina preparation and the _Bacillus subtilis_, the endophyte weight was 2.84 g. The length of roots ranged from 12.6 to 20.9 cm (Table 2). The highest values were noted after the coinoculation of seeds with the _Bradyrhizobium_ bacteria isolated from the Nitrolora preparation and the _Pseudomonas fluorescens_ endophyte (variant eight). The analysis of the weight of the belowground parts revealed the highest values in variant five (inoculation with the _Bacillus subtilis_ endophyte only)--1.01 g, in variant eight (coinocation with the _Bradyrhizobium_ bacteria isolated from the Nitrolora preparation and the _Pseudomonas fluorescens_ endophyte)--0.97 g, and in variant two (inoculation with bacteria of the _Bradyrhizobium_ genus isolated from the Nitragina preparation--0.96 g. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & _Bradyrhizobium_ **sp.** & _Bradyrhizobium_ **sp.** & _Pseudomonas_ & _Bacillus_ \\  & **(Isolated from** & **(Isolated from** & _fluorescens_ & _subtilis_ \\  & **Nitragina Preparation)** & **Nitroflora Preparation)** & _Pseudomonas_ & _Bacillus_ \\ \hline _Bradyrhizobium_ **sp. (isolated from** & & & & \\ Nitragina preparation) & X & - & - & - \\ \hline _Bradyrhizobium_ & & & & \\ sp. (isolated from Nitrolora preparation) & - & X & - & - \\ \hline _Pseudomonas fluorescens_ & - & - & X & - \\ \hline _Bacillus subtilis_ & - & - & - & X \\ \hline \hline \end{tabular} Explanation: ‘-’ no antagonistic interactions (no halo) between the microorganisms.  
\end{table} 
Table 1: The interactions between the symbiotic bacteria (_Bradyrhizobium_ sp.) and endophytes (_Pseudomonas fluorescens_ or _Bacillus subtilis_). Figure 1: An example showing the effect of _Pseudomonas fluorescens_ bacteria on bacteria of the _Bradyrhizobium_ genus isolated from the Nitragina preparation. Saline was used as the control variant. Principal components analysis (PCA) was applied to find dependences between the applied variants of the experiment and the length and weight of the aboveground and belowground parts of the plants (Figure 2). The first principal component explained 70.80% of the variation, whereas the second principal component explained 16.70% of the variation. Both components explained 87.50% of the total variation.