study of postemergence herbicides efficacy on bermudagrass (cynodon dactylon) control in turf mixture of landscape

abstract in order to evaluate chemical control of bermudagrass (cynodon dactylon (l.) pers.) on mixture turf: (lolium perenne 20%,poa pratensis.20%,festuca arundinacea 20% and festuca rubra commutata 40%), an experiment was conducted during 2006 in tehran, using randomized complete block design with 4 replications and 11 treatments. treatments were diclpfop methyl at 900 and 1080 g a.i. ha-1, fenoxaprop-p-ethyl at 60 and 75 g a.i. ha-1, clodinafop propargyl at 48 and 64 g a.i. ha-1, tralkoxydim at 250 and 300 g a.i. ha-1, sulfusulfuron at 18.9 and 24.5 g a.i. ha-1 and untreated control. all treatments were repeated 4 times during the growth period of bermudagrass. the results showed that bermudagrass's biomass decreased by fenoxaprop-p-ethyl, clodinafop propargyl and tralkoxydim, 20-30, 40-50 and 45-55 percent, respectively. bermudagrass's density decreased by mentioned treatments, 20-25, 35-40, 5-10 percent, respectively. bemudagrass's biomass decreased by diclofop methyl treratments, 15-25 percent, respectively, but bermudagrass's density did not decrease with mentioned treatments. bermudagrass's biomass and density did not decrese by sulfosulfuron treatments. turgrass damaged by diclofop methyl and clodinafop methyl treatments more than 20 percent (biomass and visual rating). the other treatments did not damage turfgrass and did not decrease turfgrass biomass. at the end, despite of having low efficacy, fenoxaprop-p-ethyl at 60 g a.i. ha-1 (without significant differences between both doses) is recommended for bermudagrass’s control in mixture turf with mentioned mixtures, because of no damaging turf.