Effect of sulphur-based γ-poly glutamic acid fertiliser on field performance of sweet sorghum and Italian ryegrass

To evaluate the effect of sulphur-based γ-poly glutamic acid fertiliser (S-based γ-PGA fertiliser) on sweet sorghum (Sorghum bicolor) and Italian ryegrass (Lolium multiflorum), we studied their growth performance and N uptake efficiency under different N application levels in pot tests with urea and S-based fertiliser as control. The results showed that under treatment by S-based γ-PGA fertilizer, sorghum yield, crude protein content, and N uptake efficiency were better than that in the control group at N application levels of 150 and 225 kg N·ha-1. There was no difference in the growth performance of Italian ryegrass compared to that in the control, whereas the N uptake efficiency was higher than that in the control at 75 and 150 kg N·ha-1. The results suggested that S-based γ-PGA fertiliser has a better effect than that of urea and S-based fertiliser, the yield and quality of sweet sorghum and Italian ryegrass can be improved, and that the N uptake efficiency is high.