# The Effect of Meat and Bone Meal on Yield and Herbage Quality in Silage Maize
## 2 Materials and Methods
### Experimental Setup  
Five experimental variants were assumed: (1) without fertilization (zero-fert); (2) inorganic nitrogen, phosphorus, and potassium (inorganic NPK); (3) 1.0 Mg-ha\({}^{-1}\) MBM; (4) 1.5 Mg-ha\({}^{-1}\) MBM; (5) 2.0 Mg-ha\({}^{-1}\) MBM (Table 1). In this experiment, the MBM rates were adopted based on our results from previously conducted pot and field studies. Constant rates of N and K fertilizers, 158 kg-ha\({}^{-1}\) and 145 kg-ha\({}^{-1}\), respectively, and increasing P fertilizer rates of 0.0, 45, 68, and 90 kg-ha\({}^{-1}\) were used. In the NPK treatment (No. 2), 45 kg P-ha\({}^{-1}\) was used as granular triple superphosphate (20.1% P). In treatment No. 3 (45 kg P), No. 4 (68 kg P), and No. 5 (90 kg P), P was provided only with MBM that was applied each year at 1.0, 1.5, and 2.0 Mg-ha\({}^{-1}\) before sowing and after mixing with soil. In sequence, to maintain a consistent level of N fertilization (158 kg-ha\({}^{-1}\)), mineral N was added to MBM at 79 kg-ha\({}^{-1}\) in treatment No. 3 and 40 kg-ha\({}^{-1}\) in treatment No. 4, as urea (46% N) or ammonium nitrate (34% N). Since MBM has low K content (approx. 3.3 g-kg\({}^{-1}\) DM), K was used prior to sowing in mineral form (potash salt, 49.8% K) at a constant rate (145 kg-ha\({}^{-1}\)) in all treatments except zero-fert (No. 1).  
Maize was planted on 5 May 2014, 29 April 2019, and 8 May 2020, and herbage was harvested on 22, 24, and 23 September, correspondingly, in the milk-dough stage. Winter rye, winter wheat, and maize were the forecrops of silage maize grown in the first, sixth, and seventh years of the long-term experiment, respectively. Maize was grown on the same 20 plots, each with a surface area of 20 m\({}^{2}\) (4 m \(\times\) 5 m). Each year, skimming, narrowing, and plowing were carried out in the fall, and cultivator tillage and harboring were carried out in the spring before sowing. The appropriate doses of MBM and rates of mineral fertilizers were then applied by thorough mixing with the soil during harrowing. Maize seeds were sown at a depth of 5-8 cm and 75 cm row spacing, using a single-seed drill. Plant density was 8-9 plants per m\({}^{2}\). The following pre-emergent herbicides were applied: Lumax 537.5 SE (mesotrine, s-metolachlor, terbuthylazine) at 4.0 dm\({}^{-3}\)-ha\({}^{-1}\) in 2014 and 2019 and Adengo 315 SC (thiencarbazone-methyl and isosxfalitude) at 0.4 dm\({}^{-3}\)-ha\({}^{-1}\) in 2020. Seedling emergence was observed after 18-20 days. In 2014, the insecticide Karate Zeon 050 CS (lambda-cyhalothrin) was applied at 0.12 dm\({}^{-3}\)-ha\({}^{-1}\) in the 5-6 leaves unfolded stages (BBCH 15-16), and the treatment was repeated after two weeks. In 2019, the insecticide Proteus 110 OD (thiachloprid, deltamethrin) was applied at 0.5 dm\({}^{-3}\)-ha\({}^{-1}\) in the 4-5 leaves unfolded stages (BBCH 14-15). In 2020, insecticides were not applied because pest infestation of maize plants was below the action threshold. All agronomic and protective treatments were applied at the optimum dates, in accordance with the requirements for maize cultivation. At harvest, herbage yield was determined in terms  
\begin{table}
\begin{tabular}{c c c c c} \hline
**Treatment** & **N** & **P** & **N:P 1** & **K** \\ \hline
1. Zero-fert 2 & 0 & 0 & 0 & 0 \\
2. Inorganic NPK 3 & 158 & 45 & 1:0.3 & 145 \\
3. 1.0 Mg MBM + N\({}_{79}\)4 & 158 (79 + 79) & 45 & 1:0.3 & 145 \\
4. 1.5 Mg MBM + N\({}_{40}\)5 & 158 (118 + 40) & 68 & 1:0.4 & 145 \\
5. 2.0 Mg MBM 6 & 158 & 90 & 1:0.6 & 145 \\ \hline \end{tabular}
\end{table}
Table 1: Yearly dose of nitrogen (N), phosphorus (P), and potassium (K) used with meat and bone meal (MBM) and mineral fertilizers (kg-ha\({}^{-1}\)) to silage maize (2014, 2019, and 2020).  
of weight after threshing in each plot. The moisture content of the harvested crop was measured and converted to a standard moisture content (70%).