Giant miscanthus is under consideration as a biofuel crop in the United States; however, there is little information on weed management for the establishment and survival of this crop. Therefore, greenhouse and field studies using ornamental pots were conducted in summer 2011 at Tifton, GA, with the objective of screening potential PPI, PRE, and POST herbicides and herbicide combinations for giant miscanthus when establishing from vegetative rhizomes. For the POST treatments, giant miscanthus was established from rhizomes in 7.6-L containers in the field and treated with 27 POST herbicides to evaluate efficacy. Thifensulfuron, metsulfuron, tribenuron, chlorimuron, halosulfuron, rimsulfuron, cloransulam, pinoxaden, bentazon, and metribuzin did not significantly lower shoot height, reduce shoot dry weight, or increase injury compared with nontreated control (NTC) when evaluated at 4 wk after treatment. Nicosulfuron, trifloxysulfuron, sulfometuron, clodinafop, fluazifop, and pyrithiobac caused the greatest injury, reduced plant height, and reduced dry weights compared with the NTC. Sethoxydim, diclofop, flumioxazin, imazamox, imazapic, and imazethapyr decreased plant heights or resulted in increased injury. PPI and PRE treatments included 21 herbicides and herbicide combinations applied at two rates. Results indicated that most treatments containing atrazine, metribuzin, pendimethalin, acetochlor, metolachlor, and mesotrione did not injure or stunt growth; however, EPTC at 4.5 kg ai ha−1 significantly reduced height and dry weight and oxadiazon resulted in greater injury compared with NTC at both rates. These results indicate that PPI, PRE, and POST herbicides can be utilized for establishment of giant miscanthus from vegetative rhizomes. Considering the invasive potential of giant miscanthus, several POST herbicides evaluated in this study such as fluazifop, pyrithiobac, and sulfometuron may be viable options to control this species if it becomes invasive.
Nomenclature: Acetochlor; atrazine; bentazon; chlorimuron; clodinafop; cloransulam; diclofop; EPTC; fluazifop; flumioxazin; halosulfuron; imazamox; imazapic; imazethapyr; mesotrione; metribuzin; metolachlor; metsulfuron; nicosulfuron; oxadiazon; pendimethalin; pinoxaden; pyrithiobac; rimsulfuron; sethoxydim; sulfometuron; thifensulturon; tribenuron; trifloxysulfuron; giant miscanthus, Miscanthus × giganteus.
Se está considerando a Miscanthus × giganteus (miscanthus) como cultivo para biocombustibles en los Estados Unidos. Sin embargo, hay poca información acerca del manejo de malezas para el establecimiento y supervivencia de este cultivo. Por esta razón, en el verano 2011 en Tifton, GA, se realizaron experimentos de invernadero y de campo usando macetas para ornamentales, con el objetivo de evaluar herbicidas potenciales PPI, PRE, y POST y combinaciones de herbicidas para miscanthus en establecimiento a partir de rhizomas vegetativos. Para los tratamientos POST, miscanthus se estableció a partir de rhizomas en macetas de 7.6 L en el campo y fue tratado con 27 herbicidas POST para evaluar su eficacia. Thifensulfuron, metsulfuron, tribenuron, chlorimuron, halosulfuron, rimsulfuron, cloransulam, pinoxaden, bentazon, y metribuzin no redujeron significativamente la altura o el peso seco del tejido aéreo, ni incrementaron el daño al compararse con el testigo no-tratado (NTC) cuando se evaluó a 4 semanas después del tratamiento. Nicosulfuron, trifloxysulfuron, sulfometuron, clodinafop, fluazifop, y pyrithiobac causaron el mayor daño, redujeron la altura de planta y el peso seco al compararse con NTC. Sethoxydim, diclofop, flumioxazin, imazamox, imazapic, e imazethapyr disminuyeron la altura de planta o resultaron en mayor daño. Los tratamientos PPI y PRE incluyeron 21 herbicidas y combinaciones de los herbicidas, aplicados a dos dosis. Los resultados indicaron que la mayoría
