Halosulfuron Tank Mixtures and Adjuvants for Weed Control in Pumpkin Production

Field studies were conducted to evaluate postemergence combinations of halosulfuron plus sethoxydim or clethodim with various adjuvants for effects on jack-o-lantern pumpkin (Cucurbita pepo L.) injury and yields and control of large [Digitaria sanguinalis (L.) Scop.] and smooth crabgrass [D. ischaemum (Schreb. ex Schweig.) Schreb. ex Muhl.]. Halosulfuron caused 27% and 14% pumpkin injury at 28 d after postemergence treatment (DAPT) in 2004 and 2005, respectively. Tank-mixing sethoxydim or clethodim with halosulfuron did not increase pumpkin injury compared with halosulfuron alone. Pumpkin injury from sethoxydim and clethodim alone at 28 DAPT ranged from 19% to 23% in 2004, but was only 7% to 8% in 2005. The addition of oil-based adjuvants to halosulfuron did not affect pumpkin injury compared with using a nonionic surfactant (NIS). The tank mixture of halosulfuron and sethoxydim did not affect crabgrass control regardless of adjuvant. However, the addition of halosulfuron to clethodim plus NIS reduced control of crabgrass from 89% to 77% at 28 DAPT. Crabgrass control was unaffected by the addition of halosulfuron to clethodim with crop oil concentrate (COC) or a NIS/COC blend. None of the herbicide treatments provided pumpkin yield (fruit no./ha) similar to the weed-free control. The pumpkin yield of treatments using postemergence herbicides was at least 50% less than the weed-free treatment. These low pumpkin yields were most likely the result of the combination of pumpkin injury from the herbicide applications and insufficient weed control.

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Evaluation of weed control in acetyl coA carboxylase-resistant rice with mixtures of quizalofop and auxinic herbicides

Weed Technology ◽

10.1017/wet.2019.134 ◽

2019 ◽

Vol 34 (4) ◽

pp. 498-505

Author(s):

Tameka L. Sanders ◽

Jason A. Bond ◽

Benjamin H. Lawrence ◽

Bobby R. Golden ◽

Thomas W. Allen ◽

...

Keyword(s):

Weed Control ◽

Rice Yield ◽

Field Studies ◽

Growth Stages ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa ◽

Herbicide Treatments ◽

Herbicide Mixture ◽

Sequential Treatments ◽

And Control

AbstractRice with enhanced tolerance to herbicides that inhibit acetyl coA carboxylase (ACCase) allows POST application of quizalofop, an ACCase-inhibiting herbicide. Two concurrent field studies were conducted in 2017 and 2018 near Stoneville, MS, to evaluate control of grass (Grass Study) and broadleaf (Broadleaf Study) weeds with sequential applications of quizalofop alone and in mixtures with auxinic herbicides applied in the first or second application. Sequential treatments of quizalofop were applied at 119 g ai ha−1 alone and in mixtures with labeled rates of auxinic herbicides to rice at the two- to three-leaf (EPOST) or four-leaf to one-tiller (LPOST) growth stages. In the Grass Study, no differences in rice injury or control of volunteer rice (‘CL151’ and ‘Rex’) were detected 14 and 28 d after last application (DA-LPOST). Barnyardgrass control at 14 and 28 DA-LPOST with quizalofop applied alone or with auxinic herbicides EPOST was ≥93% for all auxinic herbicide treatments except penoxsulam plus triclopyr. Barnyardgrass control was ≥96% with quizalofop applied alone and with auxinic herbicides LPOST. In the Broadleaf Study, quizalofop plus florpyrauxifen-benzyl controlled more Palmer amaranth 14 DA-LPOST than other mixtures with auxinic herbicides, and control with this treatment was greater EPOST compared with LPOST. Hemp sesbania control 14 DA-LPOST was ≤90% with quizalofop plus quinclorac LPOST, orthosulfamuron plus quinclorac LPOST, and triclopyr EPOST or LPOST. All mixtures except quinclorac and orthosulfamuron plus quinclorac LPOST controlled ivyleaf morningglory ≥91% 14 DA-LPOST. Florpyrauxifen-benzyl or triclopyr were required for volunteer soybean control >63% 14 DA-LPOST. To optimize barnyardgrass control and rice yield, penoxsulam plus triclopyr and orthosulfamuron plus quinclorac should not be mixed with quizalofop. Quizalofop mixtures with auxinic herbicides are safe and effective for controlling barnyardgrass, volunteer rice, and broadleaf weeds in ACCase-resistant rice, and the choice of herbicide mixture could be adjusted based on weed spectrum in the treated field.

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Herbicide-Resistant Canola (Brassica napus) Response and Weed Control with Postemergence Herbicides

Weed Technology ◽

10.1614/wt-05-061r.1 ◽

2006 ◽

Vol 20 (3) ◽

pp. 551-557 ◽

Cited By ~ 7

Author(s):

Timothy L. Grey ◽

Paul L. Raymer ◽

David C. Bridges

Keyword(s):

Weed Control ◽

Field Studies ◽

Italian Ryegrass ◽

Wild Radish ◽

Application Timing ◽

Herbicide Resistant ◽

Naturally Occurring ◽

And Control ◽

Postemergence Herbicides ◽

Significant Injury

Field studies were conducted to evaluate weed control in herbicide-resistant canola in Georgia. The resistant canola cultivars and respective herbicides were ‘Pioneer 45A76’ and imazamox, ‘Hyola 357RR’ and glyphosate, and ‘2573 Invigor’ and glufosinate. Weed seed of Italian ryegrass and wild radish were sown simultaneously in October with canola and control of these species was evaluated along with other naturally occurring weeds. Herbicide treatments for the respective herbicide-resistant canola cultivar were imazamox at 0.035 and 0.071 kg ai/ha, glyphosate at 0.84 and 1.64 kg ae/ha, and glufosinate at 0.5 and 1.0 kg ai/ha. Herbicides were applied at one– two-leaf (LF) and three–four-LF canola stages. There was no significant injury to any canola cultivar as a result of herbicide rate or timing of application. By midseason (February), imazamox effectively controlled wild radish, henbit, and shepherd's-purse at both rates and at both timings. When applied to three–four-LF canola, the higher rates of glyphosate and glufosinate were required to provide 75% or greater control of Italian ryegrass, wild garlic, and henbit. Glufosinate did not adequately control wild radish at either rate or application timing. Greenhouse experiments provided similar results.

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Using Reduced Rates of Postemergence Herbicides in Soybeans (Glycine max)

Weed Technology ◽

10.1017/s0890037x00033947 ◽

1991 ◽

Vol 5 (4) ◽

pp. 834-840 ◽

Cited By ~ 53

Author(s):

Daniel L. Devlin ◽

James H. Long ◽

Larry D. Maddux

Keyword(s):

Glycine Max ◽

Weed Control ◽

Field Studies ◽

Herbicide Treatments ◽

Postemergence Herbicides

Eight field studies were conducted in soybeans at seven locations in Kansas over a 3-yr period to examine the efficacy of using reduced rates of the herbicides acifluorfen, bentazon, chlorimuron, and tank mixes of acifluorfen and bentazon. POST applications of these herbicides at 1/2X rates at 2 wk after planting (WAP) resulted in broadleaf weed control similar to that obtained from standard treatments of 1X rates applied at 4 WAP at six of seven studies with acifluorfen, bentazon, and acifluorfen plus bentazon and at five of seven studies with chlorimuron. One-quarter rates applied 2 WAP were equivalent to standard treatments for broadleaf weed control in four of seven studies with acifluorfen and chlorimuron, five of seven studies with bentazon, and six of seven studies with acifluorfen plus bentazon. One cultivation at 4 WAP, increased the broadleaf weed control with all herbicide treatments.

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Response of 17 Species of Container-Grown Woody Landscape and Foliage Plants to Four Postemergence Herbicides

Journal of Environmental Horticulture ◽

10.24266/0738-2898-4.2.52 ◽

1986 ◽

Vol 4 (2) ◽

pp. 52-55

Author(s):

P.R. Gilreath ◽

J.P. Gilreath

Keyword(s):

Propanoic Acid ◽

Digitaria Sanguinalis ◽

Leaf Stage ◽

Full Sunlight ◽

Foliage Plants ◽

Herbicide Treatments ◽

Excellent Control ◽

And Control ◽

Postemergence Herbicides ◽

Quizalofop Ethyl

Postemergence applications of 2 rates of Whip [fenoxaprop-ethyl) (ethyl 2-[4-[(6 chloro-2-benzoxazolyl) oxy]-phenoxy] propanoic acid), Assure (quizalofop-ethyl) (2-[4-[6-chloro-2-quinoxalinyl) oxy]-phenoxy]-propanolc acid, Fusilade 2000 (fluazifop-p-butyl) (R-butyl 2-[4-(5) trifluoromethyl-2-pyridyloxy)-phenoxy] propanoic acid), and Poast (sethoxydim) (2-[1-(ethoxyamino) butyl]-5-[2-(ethylthio) propyl 1]-3-hydroxy-2 cyclohexene-l-one) were evaluated for phytotoxicity to 17 species of container-grown woody landscape and foliage plants and control of large crabgrass (Digitaria sanguinalis L.). Crabgrass plants were treated at the 2 to 4 and 8 to 10 leaf stages and were grown under both full sun and 40% shade. Each herbicide injured at least one species. Fusilade 2000 injured the fewest species, while Poast injured the most. Under 40% shade, control of crabgrass with 2-4 leaves was acceptable with all herbicides except 0.28 kg/ha (0.25 lb/A) Whip. All herbicides were effective when applied in the 8-10 leaf stage of growth. In full sunlight, excellent control of crabgrass at the 2-4 leaf stage was obtained with all herbicide treatments except Poast. Two weeks after application to the 8-10 leaf stage, the best control was obtained with Whip; however, by the end of 8 weeks, all treatments, except Poast, provided excellent control.

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Safety and efficacy of linuron with or without an adjuvant or S-metolachlor for POST control of Palmer amaranth (Amaranthus palmeri) in sweetpotato

Weed Technology ◽

10.1017/wet.2021.27 ◽

2021 ◽

pp. 1-18

Author(s):

Levi D. Moore ◽

Katherine M. Jennings ◽

David W. Monks ◽

Ramon G. Leon ◽

David L. Jordan ◽

...

Keyword(s):

Nonionic Surfactant ◽

Weed Control ◽

Critical Period ◽

Total Yield ◽

Field Studies ◽

Palmer Amaranth ◽

Amaranthus Palmeri ◽

Foliar Injury ◽

Protoporphyrinogen Oxidase ◽

Safety And Efficacy

Abstract Field studies were conducted to evaluate linuron for POST control of Palmer amaranth in sweetpotato to minimize reliance on protoporphyrinogen oxidase (PPO)-inhibiting herbicides. Treatments were arranged in a two by four factorial where the first factor consisted of two rates of linuron (420 and 700 g ai ha−1), and the second factor consisted of linuron applied alone or in combinations of linuron plus a nonionic surfactant (NIS) (0.5% v/v), linuron plus S-metolachlor (800 g ai ha−1), or linuron plus NIS plus S-metolachlor. In addition, S-metolachlor alone and nontreated weedy and weed-free checks were included for comparison. Treatments were applied to ‘Covington’ sweetpotato 8 d after transplanting (DAP). S-metolachlor alone provided poor Palmer amaranth control because emergence had occurred at applications. All treatments that included linuron resulted in at least 98 and 91% Palmer amaranth control 1 and 2 wk after treatment (WAT), respectively. Including NIS with linuron did not increase Palmer amaranth control compared to linuron alone, but increased sweetpotato injury and subsequently decreased total sweetpotato yield by 25%. Including S-metolachlor with linuron resulted in the greatest Palmer amaranth control 4 WAT, but increased crop foliar injury to 36% 1 WAT compared to 17% foliar injury from linuron alone. Marketable and total sweetpotato yield was similar between linuron alone and linuron plus S-metolachlor or S-metolachlor plus NIS treatments, though all treatments resulted in at least 39% less total yield than the weed-free check resulting from herbicide injury and/or Palmer amaranth competition. Because of the excellent POST Palmer amaranth control from linuron 1 WAT, a system including linuron applied 7 DAP followed by S-metolachlor applied 14 DAP could help to extend residual Palmer amaranth control further into the critical period of weed control while minimizing sweetpotato injury.

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The Influence of Weed Management in Wheat (Triticum aestivum) Stubble on Weed Control in Corn (Zea mays)

Weed Technology ◽

10.1017/s0890037x00044249 ◽

1998 ◽

Vol 12 (3) ◽

pp. 522-526 ◽

Cited By ~ 7

Author(s):

Theodore M. Webster ◽

John Cardina ◽

Mark M. Loux

Keyword(s):

Weed Control ◽

Weed Management ◽

Management Practices ◽

Field Studies ◽

Giant Foxtail ◽

Giant Ragweed ◽

Herbicide Treatments ◽

Postharvest Treatment ◽

Full Rate ◽

Wheat Stubble

The objectives of this study were to determine how the timing of weed management treatments in winter wheat stubble affects weed control the following season and to determine if spring herbicide rates in corn can be reduced with appropriately timed stubble management practices. Field studies were conducted at two sites in Ohio between 1993 and 1995. Wheat stubble treatments consisted of glyphosate (0.84 kg ae/ha) plus 2,4-D (0.48 kg ae/ha) applied in July, August, or September, or at all three timings, and a nontreated control. In the following season, spring herbicide treatments consisted of a full rate of atrazine (1.7 kg ai/ha) plus alachlor (2.8 kg ai/ha) preemergence, a half rate of these herbicides, or no spring herbicide treatment. Across all locations, a postharvest treatment of glyphosate plus 2,4-D followed by alachlor plus atrazine at half or full rates in the spring controlled all broadleaf weeds, except giant ragweed, at least 88%. Giant foxtail control at three locations was at least 83% when a postharvest glyphosate plus 2,4-D treatment was followed by spring applications of alachlor plus atrazine at half or full rates. Weed control in treatments without alachlor plus atrazine was variable, although broadleaf control from July and August glyphosate plus 2,4-D applications was greater than from September applications. Where alachlor and atrazine were not applied, August was generally the best timing of herbicide applications to wheat stubble for reducing weed populations the following season.

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Response of Johnsongrass (Sorghum halepense) and Imidazolinone-Resistant Corn (Zea mays) to AC 263,222

Weed Technology ◽

10.1017/s0890037x00046078 ◽

1999 ◽

Vol 13 (3) ◽

pp. 484-488 ◽

Cited By ~ 11

Author(s):

John W. Wilcut ◽

John S. Richburg ◽

F. Robert Walls

Keyword(s):

Zea Mays ◽

Weed Control ◽

Untreated Control ◽

Field Studies ◽

Sorghum Halepense ◽

Corn Yield ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Ac 263,222 ◽

Large Crabgrass

Field studies were conducted in 1992 and 1993 to evaluate AC 263,222 applied postemergence (POST) alone and as a mixture with atrazine or bentazon for weed control in imidazolinone-resistant corn. Nicosulfuron alone and nicosulfuron plus atrazine were also evaluated. Herbicide treatments were applied following surface-banded applications of two insecticides, carbofuran or terbufos at planting. Crop sensitivity to POST herbicides, corn yield, and weed control was not affected by insecticide treatments. AC 263,222 at 36 and 72 g ai/ha controlled rhizomatous johnsongrass 88 and 99%, respectively, which was equivalent to nicosulfuron applied alone or with atrazine. AC 263,222 at 72 g/ha controlled large crabgrass 99% and redroot pigweed 100%, and this level of control exceeded that obtained with nicosulfuron alone. AC 263,222 at 72 g/ha controlled sicklepod and morningglory species 99 and 98%, respectively. Nicosulfuron alone or with atrazine controlled these two species less than AC 263,222 at 72 g/ha. Addition of bentazon or atrazine to AC 263,222 did not improve control of any species compared with the higher rate of AC 263,222 at 72 g/ha applied alone. Corn yield increased over the untreated control when POST herbicide(s) were applied, but there were no differences in yield among herbicide treatments.

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Integration of residual herbicides with cover crop termination in soybean

Weed Technology ◽

10.1017/wet.2019.111 ◽

2019 ◽

Vol 34 (1) ◽

pp. 11-18 ◽

Cited By ~ 2

Author(s):

Derek M. Whalen ◽

Lovreet S. Shergill ◽

Lyle P. Kinne ◽

Mandy D. Bish ◽

Kevin W. Bradley

Keyword(s):

Weed Control ◽

Cover Crops ◽

Cover Crop ◽

Biomass Accumulation ◽

Field Studies ◽

Italian Ryegrass ◽

Cereal Rye ◽

Herbicide Treatments ◽

Residual Herbicide ◽

Herbicide Programs

AbstractCover crops have increased in popularity in midwestern U.S. corn and soybean systems in recent years. However, little research has been conducted to evaluate how cover crops and residual herbicides are effectively integrated together for weed control in a soybean production system. Field studies were conducted in 2016 and 2017 to evaluate summer annual weed control and to determine the effect of cover crop biomass on residual herbicide reaching the soil. The herbicide treatments consisted of preplant (PP) applications of glyphosate plus 2,4-D with or without sulfentrazone plus chlorimuron at two different timings, 21 and 7 d prior to soybean planting (DPP). Cover crops evaluated included winter vetch, cereal rye, Italian ryegrass, oat, Austrian winter pea, winter wheat, and a winter vetch plus cereal rye mixture. Herbicide treatments were applied to tilled and nontilled soil without cover crop for comparison. The tillage treatment resulted in low weed biomass at all collection intervals after both application timings, which corresponded to tilled soil having the highest sulfentrazone concentration (171 ng g−1) compared with all cover crop treatments. When applied PP, herbicide treatments applied 21 DPP with sulfentrazone had greater weed (93%) and waterhemp (89%) control than when applied 7 DPP (60% and 69%, respectively). When applied POST, herbicide treatments with a residual herbicide resulted in greater weed and waterhemp control at 7 DPP (83% and 77%, respectively) than at 21 DPP (74% and 61%, respectively). Herbicide programs that included a residual herbicide had the highest soybean yields (≥3,403 kg ha−1). Results from this study indicate that residual herbicides can be effectively integrated either PP or POST in conjunction with cover crop termination applications, but termination timing and biomass accumulation will affect the amount of sulfentrazone reaching the soil.

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Weed control with reduced rates of imazaquin and imazethapyr in no-till narrow-row soybean (Glycine max)

Weed Science ◽

10.1017/s004317450009024x ◽

1998 ◽

Vol 46 (1) ◽

pp. 105-110 ◽

Cited By ~ 10

Author(s):

William G. Johnson ◽

Jeffrey S. Dilbeck ◽

Michael S. DeFelice ◽

J. Andrew Kendig

Keyword(s):

Glycine Max ◽

Weed Control ◽

Field Studies ◽

Net Income ◽

Crop Response ◽

Soybean Production ◽

No Till ◽

Giant Foxtail ◽

Herbicide Treatments ◽

Narrow Row

Field studies were conducted at three locations in 1993 and 1994 to evaluate weed control and crop response to metolachlor plus combinations of 0.5 × and 1 × label rates of imazaquin applied preplant and imazethapyr applied early postemergence or postemergence in no-till narrow-row soybean production. Giant foxtail, common ragweed, common cocklebur, and large crabgrass population reductions were greater with sequential preplant metolachlor plus imazaquin followed by early postemergence or postemergence imazethapyr than with preplant metolachlor plus imazaquin or early postemergence/postemergence imazethapyr alone. Ivyleaf morningglory was not effectively controlled by any herbicide program. Pennsylvania smartweed populations were reduced with all herbicide treatments. Soybean yields with treatments utilizing 0.5 × rates were usually equal to 1 × rates if imazethapyr was applied early postemergence or postemergence. Net income with reduced herbicide rates was equal to full-label rates and provided no greater risk to net income.

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Weed Management in Imidazolinone-Resistant Corn with Imazapic

Weed Technology ◽

10.1614/wt-03-204r ◽

2004 ◽

Vol 18 (4) ◽

pp. 1018-1022 ◽

Cited By ~ 6

Author(s):

Joyce Tredaway Ducar ◽

John W. Wilcut ◽

John S. Richburg

Keyword(s):

Weed Control ◽

Weed Management ◽

Rate Control ◽

Field Studies ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Rate Controlled ◽

Prickly Sida ◽

Better Than ◽

Large Crabgrass

Field studies were conducted in 1992 and 1993 to evaluate imazapic alone and in postemergence (POST) mixtures with atrazine or bentazon for weed control in imidazolinone-resistant corn treated with carbofuran. Nicosulfuron and nicosulfuron plus atrazine also were evaluated. Imazapic at 36 and 72 g ai/ha controlled large crabgrass 85 and 92%, respectively, which was equivalent to control obtained with nicosulfuron plus atrazine. Imazapic at the higher rate controlled large crabgrass better than nicosulfuron alone. Imazapic at 36 and 72 g/ha controlled Texas panicum 88 and 99%, respectively, and at the higher rate control was equivalent to that obtained with nicosulfuron alone or in mixture with atrazine. Imazapic plus bentazon POST controlled Texas panicum less than imazapic at the lower rate applied alone. Redroot pigweed was controlled 100% with all herbicide treatments. Imazapic at either rate alone or in tank mixture with bentazon or atrazine controlled prickly sida >99%, which was superior to control obtained with nicosulfuron or nicosulfuron plus atrazine. Smallflower, entireleaf, ivyleaf, pitted, and tall morningglories were controlled 96% or greater with all herbicide treatments except nicosulfuron alone. Sicklepod control was >88% with all imazapic treatments, whereas control from nicosulfuron alone was 72%. Corn yields were improved by the addition of POST herbicides with no differences among POST herbicide treatments.

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