A field experiment was conducted to evaluate the effects of two nitrogen levels (N: 0,100 kg ha -1 ) and four phosphorus levels (P: 0, 60, 90, 120 kg P2O5 ha -1 ) on smooth bromegrass (Bromus inermis Leyss.) seed quality by measuring germination, mean germination time (MGT), protein and phosphorus contents, acid phosphoesterase (APT) and antioxidant enzymes activities, hydrogen peroxide (H2O2) ...