interaction between accase inhibitors and broadleaf herbicides to the control of italian ryegrass

Management of italian ryegrass is frequently done with tank-mix or sequential applications of herbicides. this study aimed to evaluate the interaction of haloxyfop-pmethyl or clethodim with 2,4-d, chlorimuron-ethyl, and cloransulam-methyl applied in a tank mix or sequential in the control of italian ryegrass. the three experiments were performed in a factorial arrangement, and a randomized complete block was designed with four replications. factor a consisted of the haloxyfop (62.35 g a.i. ha-1 ), clethodim (108 g a.i. ha-1 ) and chlorimuron (20 g a.i. ha-1 ) (experiment i); haloxyfop, clethodim and cloransulam (39.95g a.i. ha-1 ) (experiment ii); haloxyfop, clethodim and 2,4-d (1005 g a.e. ha-1 ) (experiment iii). factor b consisted of tank-mix or sequential (same day) application. treatments also included an untreated check and the isolated application of herbicides. haloxyfop and clethodim alone, clethodim+2,4-d, haloxyfop+cloransulam, haloxyfop+chlorimuron, clethodim+cloransulam, clethodim+chlorimuron controlled italian ryegrass. however, an antagonistic response of haloxyfop+2,4-d was observed. based on this study, haloxyfop should not be associated with 2,4-d in the control of italian ryegrass; however, the mixtures of accase+chlorimuron, accase+cloransulam, and clethodim+2,4-d were efficient in the control of the italian ryegrass.