## 2 Materials and Methods  
### Experimental Design, Growing Conditions and Treatments  
UPTOHERE The research experiment was carried out at the Educational and Experimental Station in Tomaszkowo (53\({}^{\circ}\)71\({}^{\prime}\) N, 20\({}^{\circ}\)43\({}^{\prime}\) E), Poland. The experiments were carried out in the years 2017-2019 using commercial bacterial preparations that are currently used in the cultivation of winter wheat (_Triticum aestivum_ L.). The method employed was that of a static field experiment carried out in four replicates in a randomised block design. The area of the seeding plot was 9.90 m\({}^{2}\) and that of the harvest plot was 8.00 m\({}^{2}\). Winter wheat of the KWS OZON cultivar was sown annually in succession, with winter triticale as the nurse crop in 2016. The wheat was sown at a density of 500 seeds-m\({}^{-2}\), with a row spacing of 12.5 cm.  
was 10.0 g kg\({}^{-1}\), and the total nitrogen content was 0.99 g kg\({}^{-1}\). The soil abundance in available nutrients was high for P (85.1 mg kg\({}^{-1}\)) and medium for K (155.0 mg kg\({}^{-1}\)). Weather conditions registered during field trials are presented in Table 1. The factor under research was the application of commercial bacterial preparations in combination with NPK mineral fertilisers (Table 2).  
The sowing, cultivation treatment and harvesting of the wheat were carried out in accordance with the agrotechnical requirements specific to the plant species. No protection against pests or diseases was performed. Weeds were controlled using herbicides: BBCH 31-32-Axial 50 EC 0.8 L/ha (pinoxaden)-50 g/L (5.05%), Mustang Forte 195 SE 1.0 L/ha (Florasulam-5 g/L Aminopyralid-10 g/L, 2,4-D-180 g/L).  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Growing**} & \multicolumn{8}{c}{**Mean Temperature (\({}^{\circ}\)C)**} \\ \cline{2-10} Season & IX * & X & XI-III & IV & V & VI & VII & VIII & Av. \\ \hline
2016/2017 & 13.6 & 6.1 & 2.4 & 5.7 & 12.1 & 15.7 & 16.8 & 17.4 & 7.5 \\
2017/2018 & 12.8 & 8.7 & 3.9 & 10.8 & 15.7 & 17.2 & 19.7 & 19.2 & 8.6 \\
2018/2019 & 14.5 & 8.7 & 3.3 & 8.0 & 11.6 & 20.2 & 17.1 & 18.5 & 8.8 \\
1981–2010 & 12.8 & 8.0 & 2.9 & 7.7 & 13.5 & 16.1 & 18.7 & 17.9 & 7.9 \\ \hline \multicolumn{10}{c}{Rainfall (mm)} & \multicolumn{8}{c}{} & \multicolumn{2}{c}{} & \multicolumn{2}{c}{} & \multicolumn{2}{c}{} & \multicolumn{2}{c}{} \\
2016/2017 & 21.1 & 104.3 & 84.8 & 59.1 & 25.1 & 74.5 & 107.6 & 63.1 & 693.8 \\
2017/2018 & 168.1 & 114.9 & 42.4 & 33.5 & 25.0 & 53.7 & 141.0 & 44.6 & 713.4 \\
2018/2019 & 20.3 & 84.7 & 16.0 & 0.0 & 142.8 & 120.6 & 56.3 & 55.9 & 677.6 \\
1981–2010 & 56.9 & 42.6 & 44.8 & 33.3 & 58.5 & 80.4 & 74.2 & 59.4 & 581.8 \\ \hline \hline \end{tabular} \({}^{\star}\)Month/Phenological growth stages (BBCH scale): IX/germination–leaf development (BBCH 00–19); X/filtering (BBCH 20...); XI-III/winter dormancy; IV/starting vegetation; V/stem elongation–booting (BBCH 30–49); V/Influorescence emergence, heading–flowering, anthesis (BBCH 51–69); VII/development of fruit-e Senescence (BBCH 71–99); VIII/harvesting.  
\end{table}
Table 1: Monthly air temperature and monthly rainfall in the 2016–2019 season. Meteorological data against the years 1981–2010 (Data obtained from the Meteorological Station at Tomaszkowo (53°71° N, 20°43° E), Poland).  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multicolumn{1}{c}{**Treatment (Shortcut)**} & \multicolumn{1}{c}{**Component**} & \multicolumn{1}{c}{**Application Date/Dose**} \\ \hline \hline \multirow{5}{*}{NPK (NPK)} & N (ammonium sulphate 34%; & BBCH\({}_{23-24}\)/90.0 kg ha\({}^{-1}\) \\  & N (ammonium sulphate 34%; & BBCH\({}_{31-32}\)/60.0 kg ha\({}^{-1}\) \\  & P (triple superphosphate 20%); & Pre-sowing/70.0 kg ha\({}^{-1}\) \\  & K (potash salt, 49.8%) & Pre-sowing/100.0 kg ha\({}^{-1}\) \\ \cline{2-3} \cline{2-