The Effect of Biogas Slurry Application on Biomass Production and Forage Quality of Lolium Multiflorum

The development of ecological circular agriculture has been highly encouraged to recycle agricultural wastes, reduce mineral fertilizer input, and protect the environment. Biogas slurry (BS), a by-product of biogas production generated from anaerobic digestion of animal waste and crop residues, is often considered a substitute to reduce mineral fertilizer input. Being a cheap source of organic matter and plant nutrients, its application may improve soil fertility and yield quality and quantity. The field experiments were conducted in 2016 and 2017 to study the plant growth responses and forage quality by applying biogas slurry to replace chemical synthetic fertilizer (CSF). Results revealed that biogas slurry combination with chemical synthetic fertilizer significantly (p < 0.05) improved the growth of Italian ryegrass on treatment with T2, and the Italian ryegrass dry matter was increased by more than 9.00%, while the stem-to-leaf ratio was decreased by more than 12% (second cutting), in comparison with only chemical synthetic fertilizer group. In the case of forage quality, the crude protein (CP) and crude fiber (CF) content had a significant difference was observed between the T0 and T2 treatment group. Compare with the chemical synthetic fertilizer group, the CP content improved by 10.35%, and the CF content decreased about 10.00%. Based on these results, it was concluded that the application of 37.5 kg/ha CSF + 100.5 t/ha BS could improve the production of biomass and forage quality in Italian ryegrass.

Automated summary

The study found that using biogas slurry as a substitute for chemical synthetic fertilizer can significantly improve the growth and forage quality of Italian ryegrass. The application of biogas slurry can improve soil fertility, increase crop yield, and enhance crop quality.