Response of Energycane to Preemergence and Postemergence Herbicides

Energycane has been proposed as a potential, perennial bioenergy crop for lignocellulosic-derived fuel production in the United States. Herbicides currently used in sugarcane and other crops can potentially be used in energycane if there is acceptable tolerance. Also, to limit future invasion of energycane escapes, herbicides used for perennial grass control could potentially be used for management of escapes. In container studies conducted outside, aboveground and belowground biomass of energycane was measured to evaluate energycane tolerance to 9 PRE and 19 POST herbicides used in sugarcane and other crops. PRE application of atrazine, diuron, mesotrione, metribuzin, pendimethalin, and Smetolachlor at rates labeled for sugarcane did not significantly injure (<3%) or reduce energycane biomass compared with the nontreated plants 28 and 56 d after treatment (DAT). Injury from clomazone (54%), flumioxazin (7%), and hexazinone (29%) was observed 28 DAT. Injury from flumioxazin was transient and was not observed at 56 DAT. At 56 DAT, energycane injury increased to 71 and 98%, respectively, for clomazone and hexazinone. Hexazinone and clomazone applied PRE significantly reduced biomass compared with the nontreated plants. At 28 DAT, POST application of 2,4-D amine, ametryn, asulam, atrazine, carfentrazone, dicamba, halosulfuron, mesotrione, metribuzin, and trifloxysulfuron at labeled rates for sugarcane did not injure or significantly reduce energycane biomass compared with the nontreated plants. Injury was observed when clethodim (99%), clomazone (51%), diuron (51%), flumioxazin (21%), glufosinate (84%), glyphosate (100%), hexazinone (100%), paraquat (66%), and sethoxydim (100%) were applied POST, and each of these treatments reduced energycane biomass compared with the nontreated plants. These results show that several PRE and POST herbicides used for weed management in sugarcane may potentially be used in energycane for weed control. Also, based on our results, clethodim, glyphosate, and sethoxydim would be effective for management of energycane escapes.