Abstract: Perennial ryegrass (Lolium perenne), a fine forage grass, is widely used in animal husbandry. Previous studies reported that application of fungi Aspergillus aculeatus could improve stress resistance and growth of perennial ryegrass. In this study, we investigated the effects of A. aculeatus application on perennial ryegrass growth, yield, hay yield, forage quality, mineral element content, growth phytohormones and metabolites under field conditions. Exogenous A. aculeatusapplication significantly increased the biomass, yield, hay yield of perennial ryegrass as well as the contents of N, P, K, Ca and Mn in leaves. Furthermore, leaves of perennial ryegrass treated with A. aculeatus had higher concentrations of crude protein and crude fat. Application of A. aculeatus had significant effects on growth phytohormones as well as metabolites of perennial ryegrass. These results provide a theoretical basis for further application of A. aculeatus on perennial ryegrass.

Key words: ecological behavior, phycosphere microbes, phytoplankton, matter cycling, co-evolution.