Effects of rhizosphere soil of Achnatherum inebrians on forages seed germination

In order to investigate the allelopathy of aqueous extracts from rhizosphere soil of Achnatherum inebrians on the seed germination of forages, the influence of aqueous extract of rhizosphere soil from autumn A. inebrians in 0-5, 5-10, 10-15, 15-20 cm layer with the concentrations of 2, 1, 0.2, 0.1 g·mL-1 on the seed germination of Bromus inermis, Medicago sativa, Onobrychis viciaefolia were studied through the standard germination test. The result showed that effects of aqueous extract of rhizosphere soil on the germination rate, germination potential, germination index, radicle length, shoot length, root to shoot weight of three pasture seed were not consistent. Based on the index of comprehensive allelopathic effects, the intensity of restriction to germination of three forages were in the order of M. sativaB. inermisO. viciaefolia. The aqueous extracts had no inhibition on B. inermis and O. viciaefolia seed germination whereas they had some inhibition on M. sativa seed germination which increased with the increase of extract concentration. The aqueous extract in 5-10, 10-15 and 15-20 cm layer from each layer promoted seed germination of B. inermis, O. viciaefolia whereas they had inhibition on M. sativa seed germination which had significant inhibition (P0.05). The aqueous extract of rhizosphere soil from A. inebrians with 0.2 g·mL-1 concentrations had significantly promoted(P0.05) the seed germination of B. inermis and O. viciaefolia. The allelopathy of other aqueous extracts concentrations did not perform consistently which decreased with the concentrations increasing.