THE EFFECT OF DIFFERENT IRRIGATION LEVEL AND NITROGEN DOSES ON THE SILAGE YIELD AND QUALITY OF SORGHUM × SUDAN GRASS HYBRID (Sorghum bicolor L. × Sorghum sudanese)

This study aimed to determine the effects of different irrigation levels (I30, I60, and I100) and nitrogen doses (N0, N50, N100, and N150 kg ha-1) on the silage yield and quality of sorghum × Sudan grass hybrids (Sorghum bicolor L. × Sorghum sudanese). The experiment was conducted via a split-plot trial design with three replicates over two years, 2021 and 2022. Silage yield was evaluated over two years, and quality traits were evaluated over one year. Silage yield, irrigation water use efficiency (IWUE), water use efficiency (WUE), dry matter, pH, organic acids (lactic and acetic), relative feed value (RFV), crude protein, potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), total phenolic and total flavonoid content, DPPH free radical scavenging activity, and condensed tannin content were determined in the silage samples. The highest silage yield was observed in the I100×N1000 (64.3 t ha-1) and I100×N150 (61.8 t ha-1) treatments. The highest WUE was obtained from the I30×N150 interaction, whereas the highest IWUE value was obtained from the I30×N150 interaction. The lactic acid and crude protein contents of the silages ranged from 2.29-4.38% and from 6.51-9.70%, respectively. As a result, the silage yield decreased, whereas the silage quality was not affected by stress conditions. Accordingly, the I100xN1000 interaction, which results in the highest silage yield, is recommended.