Influence of Antidotes on Forage Grass Seedling Response to Metolachlor and Butylate

Abstract

Field studies were conducted for 3 yr near Mead, NE, to evaluate the effectiveness of seed safeners CGA-92194 [N-(1,3-dioxalon-2-yl-methoxy)iminobenzeneacetonitrile], NA (1,8-naphthalic anhydride), and R-29148 (2,2-dimethyl-5-methyldichloroacetyloxazolidine) to reduce herbicide injury to big bluestem (Andropogon gerardiiVitman), indiangrass[Sorghastrum nutans(L.) Nash], intermediate wheatgrass[Agropyron intermedium(Host.) Beauv.], sideoats grama[Bouteloua curtipendula(Michx.) Torr.], and switchgrass (Panicum virgatumL.) from preplant-incorporated butylate [5-ethyl bis-(2-methylpropyl)carbamothioate] and metolachlor [2-chloro-N- (2-ethyl-6-methylphenyl) -N- (2-methoxy-l-methylethyl)acetamide], applied at 4.5 and 2.2 kg ai/ha, respectively. Big bluestem stands were satisfactory, regardless of herbicide or safener treatment, although stands were reduced by NA treatment with either herbicide. Indiangrass stands varied by year, with protection from both herbicides by R-29148 in 1984 and by NA in 1985. All safeners reduced injury to intermediate wheatgrass from metolachlor and to a lesser extent from butylate; acceptable stands were obtained with metolachlor treatment when unsafened. Sideoats grama was nearly eliminated with either herbicide, regardless of safener. Switchgrass treated with NA produced stands two- to threefold higher than other safened or unsafened seed in metolachlor plots and equal to unsafened seed in the weeded control plots.

Effect of Safener, Activated-charcoal Coated Seed, and Charcoal Banding on Establishment of Switchgrass Receiving Pre-emergent Herbicides

“…Fluxofenin is an oxime ether derivative primarily used to protect grasses from chloroacetanilide herbicides like metolachlor (2,3,13). Griffin et al (12) reported that switchgrass seedlings were safened against metolachlor with 1,8-napthalic anhydride (NA); however, NA is no longer commercially available. There is relatively little research evaluating seed safeners for improved forage establishment (20).…”

Seed Safening from Herbicidal Injury in Switchgrass Establishment

“…Seed safeners were proven effective in inducing herbicide selectivity in forages (Griffin et al, 1988). Naphthalic anhydride (NA) (naphthalene-1,8-dicarboxylic anhydride) protected perennial ryegrass (Lolium perenne L.) from alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide] yet failed to protect orchardgrass (Dactylis glomerata L.) from EPTC (S-ethyl dipropyl carbamothioate) or butam [2,2-dimethyl-N-(1-methylethyl)-N-(phenylmethyl)propanamide].…”

“…Sand bluestem (Andropogon hallii Hack.) Griffin et al (1988) demonstrated that switchgrass treated with NA and planted to metolachlor-treated fields produced solid stands (55% coverage of planted area) and could prove beneficial when atrazine-tolerant weeds were present in the seeding area. Nash] was protected from EPTC by the proprietary safener CGA-43089 (Abu-Qare and Duncan, 2002).…”

“…Nash] was protected from EPTC by the proprietary safener CGA-43089 (Abu-Qare and Duncan, 2002). Griffin et al (1988) demonstrated that switchgrass treated with NA and planted to metolachlor-treated fields produced solid stands (55% coverage of planted area) and could prove beneficial when atrazine-tolerant weeds were present in the seeding area. The use of the safener fluxofenim was effective for use in sweet sorghum in controlling annual grassy weeds but failed to safen switchgrass seed in greenhouse experiments (Butler et al, 2012).…”

“…The controlled hydration technique was conducted by first determining the amount of water to completely wet the seed lot in 5 min without any excess liquid (Finch-Savage et al, 2004;Griffin et al, 1988). Seed samples were added to premeasured, premixed water and safener and were allowed to soak and then dried for 24 h at room temperature (25°C) in open, clear, plastic Lucite boxes with constant air flow.…”