关键词: 狗牙根, 化感作用, 杂草, 抑制作用

Abstract: In order to investigate the allelopathic potential of bermudagrass(Cynodon dactylon Rich.) in weed management,a laboratory bioassay was conducted with Italian ryegrass(Lolium multiflorum Lam.),annual bluegrass(Poa annua L.),common crabgrass(Digitaria sanguinalis(L.) Scop.),barnyardgrass(Echinochloa crusgalli(L.) Beauv.) and goosegrass(Eleusine indica(L.) Gaerth.) as the acceptors.Effects of the aqueous extracts of aboveground part of bermudagrasses on seed germination rate and seeding growth of the acceptors were investigated,and 9 phenolic acids namely protocatechuic,caffeic,salicylic,syringic,ferulic,vanillic,ρ-coumaric,cinnamonic,and ρ-hydroxybenzoic acids in the aqueous extracts were quantified by high performance liquid chromatography(HPLC).The results show that the germination and seedling growth of 5 acceptor grasses,especially Italian ryegrass,common crabgrass and goosegrass,were inhibited obviously by applying the aqueous extracts,and inhibition rate by wild bermudagrass was greater than Tif-419 and Tif-328.Vanillic,ρ-coumaric and ferulic acids were detected in all of the water extracts of 4 bermudagrasses,and the protocatechuic,caffeic,salicylic,syringic,ρ-hydroxybenzoic,and cinnamonic aids were only detected in some of the aquesous extracts of the bermudagrass materials.Compared with other phenolic acids,concentration of protocatechuic acid in the aqueous extract was highest,and the change of protocatechuic acid concentration was consistent with the inhibition of the aqueous extracts on seed germination rate and seeding growth of the acceptors.Therefore,protocatechuic acid might be the most effective phenolic acid in bermudagrass on the inhibition of seed germination and seeding growth of acceptor grasses.

Key words: Bermudagrass, Allelopathic effect, Weed, Inhibition