Influence of Diclosulam Postemergence Application Timing on Weed Control and Peanut Tolerance

Field studies were conducted at Lewiston–Woodville and Rocky Mount, NC in 2001 and 2002 to evaluate weed control and peanut response to POST treatments of diclosulam at various rates and application timings. Diclosulam controlled common ragweed and entireleaf morningglory when applied within 35 d after planting (DAP). Common ragweed 61 cm tall was controlled ≥92% with 4 to 13 g ai/ha diclosulam and larger common ragweed (107 to 137 cm tall) were controlled ≥97% with 27 g/ha diclosulam. Common lambsquarters was controlled 62% or less with all diclosulam POST treatments following metolachlor applied PRE, which provided 48% control. Peanut injury was less than 15% with all diclosulam POST treatments and was transitory. In separate studies, POST diclosulam treatments did not affect peanut yield in a weed-free environment. Peanut yield in weedy environments was reduced as the diclosulam application timing was delayed because of early season weed interference. A linear relationship was observed between yield and application timing with yield decreasing as application timing was delayed. This yield response documents the importance of early season weed management for maximizing peanut yield potential. Virginia peanut varieties were not affected by different POST rates of diclosulam; however, early season peanut injury showed a linear and quadratic relationship with diclosulam rate and was less than 14% at rates as high as 71 g/ha, and was not apparent by late season.

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Efficacy and Crop Response to Glufosinate-Based Weed Management in PAT-Transformed Sweet Corn (Zea mays)

Weed Technology ◽

10.1017/s0890037x00044997 ◽

1999 ◽

Vol 13 (1) ◽

pp. 104-111 ◽

Cited By ~ 6

Author(s):

Lee R. Van Wychen ◽

R. Gordon Harvey ◽

Mark J. Vangessel ◽

Thomas L. Rabaey ◽

David J. Bach

Keyword(s):

Weed Control ◽

Weed Management ◽

Sweet Corn ◽

Field Studies ◽

Yield Response ◽

Crop Response ◽

Control Efficacy ◽

Common Ragweed ◽

Common Lambsquarters ◽

Proso Millet

Field studies were conducted at Arlington, WI, in 1996 and 1997 and at Georgetown, DE, and LeSueur, MN, in 1997 to determine weed control efficacy, crop injury, and yield response of PAT-transformed sweet corn to glufosinate-based weed management. Sequential applications of glufosinate 10 to 18 d apart at 0.4 and 0.3 kg ai/ha controlled common lambsquarters, common ragweed, velvetleaf, wild-proso millet, and fall panicum 90% or better at all locations. Weed control varied little among 0.3, 0.4, or 0.3 and 0.3 (sequential) kg/ha glufosinate rates. Glufosinate applied alone, with, or following atrazine controlled velvetleaf 90% or greater but was less consistent on common ragweed and common lambsquarters (73 to 100%). Atrazine plus metolachlor applied preemergence (PRE) and glufosinate applied alone postemergence (POST) provided inconsistent wild-proso millet and fall panicum control (43 to 99%). Metolachlor followed by glufosinate improved consistency of grass control (> 76%). Glufosinate followed by cultivation provided 80% or greater control of velvetleaf and wild-proso millet. Glufosinate did not injure or delay maturity of PAT-transformed sweet corn. Sweet corn treated with glufosinate resulted in yields greater than or equal to the sweet corn that was hand-weeded or received a standard herbicide treatment.

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Competitiveness with Weeds of Soybean Cultivars with Different Maturity and Canopy Width Characteristics

Weed Technology ◽

10.1614/wt-06-190.1 ◽

2007 ◽

Vol 21 (4) ◽

pp. 1082-1088 ◽

Cited By ~ 17

Author(s):

Dawn E. Nordby ◽

Dustin L. Alderks ◽

Emerson D. Nafziger

Keyword(s):

Weed Control ◽

Weed Management ◽

Growth Stage ◽

Competitive Ability ◽

Field Studies ◽

Yield Potential ◽

Weed Competition ◽

Early Season ◽

Soybean Cultivars ◽

Maturity Date

Field studies were conducted in 2005 at five locations throughout Illinois to determine the effect of maturity date and canopy width characteristics of selected glyphosate-resistant soybean cultivars on competitive ability against weeds. Natural weed populations at all sites were allowed to compete with the soybean cultivars until the V1, V3, V5, or V7 growth stage and then removed with an application of glyphosate. Light-interception readings, weed control ratings, and soybean yield were all measured to compare cultivars. Cultivars of later maturities tended to withstand early season weed competition better and attained higher yields when weeds were removed at later timings than those of earlier maturity. Although canopy width differed moderately among cultivars in some cases, canopy width had no effect on the ability of soybeans to compete with weeds. Thus, choosing soybean cultivars of later maturity might provide more flexibility in weed management and might reduce losses due to weeds, but that benefit needs to be balanced with yield potential.

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Application Timing for Weed Control in Corn (Zea mays) with Dicamba Tank Mixtures

Weed Technology ◽

10.1017/s0890037x00045498 ◽

1997 ◽

Vol 11 (3) ◽

pp. 602-607 ◽

Cited By ~ 4

Author(s):

Eric Spandl ◽

Thomas L. Rabaey ◽

James J. Kells ◽

R. Gordon Harvey

Keyword(s):

Zea Mays ◽

Grain Yield ◽

Weed Control ◽

Field Studies ◽

Corn Yield ◽

Application Timing ◽

Common Lambsquarters ◽

Giant Foxtail ◽

Corn Grain ◽

Corn Grain Yield

Optimal application timing for dicamba–acetamide tank mixes was examined in field studies conducted in Michigan and Wisconsin from 1993 to 1995. Dicamba was tank mixed with alachlor, metolachlor, or SAN 582H and applied at planting, 7 d after planting, and 14 d after planting. Additional dicamba plus alachlor tank mixes applied at all three timings were followed by nicosulfuron postemergence to determine the effects of noncontrolled grass weeds on corn yield. Delaying application of dicamba–acetamide tank mixes until 14 d after planting often resulted in lower and less consistent giant foxtail control compared with applications at planting or 7 d after planting. Corn grain yield was reduced at one site where giant foxtail control was lower when application was delayed until 14 d after planting. Common lambsquarters control was excellent with 7 or 14 d after planting applications. At one site, common lambsquarters control and corn yield was reduced by application at planting. Dicamba–alachlor tank mixes applied 7 d after planting provided similar weed control or corn yield, while at planting and 14 d after planting applications provided less consistent weed control or corn yield than a sequential alachlor plus dicamba treatment or an atrazine-based program.

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Weed Management in Cotton with CGA-362622, Fluometuron, and Pyrithiobac

Weed Technology ◽

10.1614/wt-03-035r ◽

2004 ◽

Vol 18 (2) ◽

pp. 268-276 ◽

Cited By ~ 24

Author(s):

Ian C. Burke ◽

John W. Wilcut

Keyword(s):

Weed Control ◽

Weed Management ◽

Management Systems ◽

Cotton Lint ◽

Common Ragweed ◽

Common Lambsquarters ◽

Pitted Morningglory ◽

Methylarsonic Acid ◽

Prickly Sida ◽

Smooth Pigweed

An experiment was conducted at five locations in North Carolina during 2000 and 2001 to evaluate weed control, crop injury, and cotton yield. Weed management systems included different combinations of pyrithiobac preemergence (PRE), fluometuron PRE, CGA-362622 postemergence (POST), pyrithiobac POST, and monosodium salt of methylarsonic acid (MSMA) plus prometryn applied late POST-directed (LAYBY). At Goldsboro in 2000, cotton was injured 74 to 78% by CGA-362622 POST when evaluated 4 to 7 d after treatment (DAT). Injury at Clayton, Goldsboro, and Lewiston in 2001 and Rocky Mount in 2000 was less than 16% 4 to 7 DAT with the same treatment and was not apparent by 62 DAT. CGA-362622 controlled common lambsquarters, common ragweed, Palmer amaranth, sicklepod, smooth pigweed, andIpomoeaspecies including entireleaf, ivyleaf, and pitted morningglory, and the addition of pyrithiobac to the herbicide system, either PRE or POST, increased control ofAmaranthusspecies, jimsonweed, and prickly sida. CGA-362622 did not control jimsonweed or prickly sida. Fluometuron PRE, pyrithiobac PRE, and MSMA plus prometryn LAYBY were beneficial for increasing weed control and cotton lint yields. Prometryn plus MSMA LAYBY increased control of common ragweed, entireleaf morningglory, jimsonweed, pitted morningglory, and smooth pigweed and provided higher cotton yields than similar systems without a LAYBY. The greatest weed control and greatest cotton lint yields required complete weed management systems that included a combination of PRE, POST, and LAYBY treatments.

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Weed control with postemergence glyphosate tank mixes in glyphosate-resistant soybean

Canadian Journal of Plant Science ◽

10.4141/cjps-2014-060 ◽

2014 ◽

Vol 94 (7) ◽

pp. 1239-1244 ◽

Cited By ~ 2

Author(s):

Kimberly D. Walsh ◽

Nader Soltani ◽

Lynette R. Brown ◽

Peter H. Sikkema

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Trials ◽

Common Ragweed ◽

Common Lambsquarters ◽

Herbicide Treatments ◽

Untreated Check

Walsh, K. D., Soltani, N., Brown, L. R. and Sikkema, P. H. 2014. Weed control with postemergence glyphosate tank mixes in glyphosate-resistant soybean. Can. J. Plant Sci. 94: 1239–1244. Six field trials were conducted over a 3-yr period (2011, 2012 and 2013) in Ontario, Canada, to evaluate various postemergence (POST) glyphosate tank mixes for weed management in glyphosate-resistant (GR) soybean. Herbicide treatments included glyphosate applied alone or mixed with acifluorfen, fomesafen, bentazon and thifensulfuron-methyl. Glyphosate tank mixtures with acifluorfen, fomesafen, bentazon and thifensulfuron-methyl caused GR soybean injury of up to 21, 11, 4 and 14% at 7 d after treatment (DAT), which was reduced to 5, 0, 0 and 2% by 28 DAT, respectively. Velvetleaf, green pigweed, common ragweed and common lambsquarters control ranged from 55 to 95, 93 to 100, 70 to 92 and 81 to 98% at 28 DAT respectively. Relative to glyphosate alone, tank mixtures with thifensulfuron-methyl provided equivalent to increased weed control, while acifluorfen, fomesafen and bentazon provided equivalent to reduced weed control. All herbicide tank mixtures resulted in higher yields (3.8–4.0 t ha−1) than the untreated check (2.7 t ha−1), and were generally equivalent to glyphosate alone (4.1 t ha−1). Results from this study indicate that the glyphosate tank mixtures evaluated did not provide a benefit over glyphosate alone.

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Weed Management in Peanut with Herbicide Combinations Containing Imazapic and Other Pesticides

Weed Technology ◽

10.1614/wt-08-041.1 ◽

2009 ◽

Vol 23 (1) ◽

pp. 6-10 ◽

Cited By ~ 8

Author(s):

David L. Jordan ◽

Sarah H. Lancaster ◽

James E. Lanier ◽

Bridget R. Lassiter ◽

P. Dewayne Johnson

Keyword(s):

North Carolina ◽

Weed Control ◽

Weed Management ◽

Common Ragweed ◽

Common Lambsquarters ◽

Yellow Nutsedge ◽

Pod Yield ◽

Final Experiment ◽

Pitted Morningglory ◽

Large Crabgrass

Research was conducted in North Carolina to compare weed control by various rates of imazapic POST alone or following diclosulam PRE. In a second experiment, weed control by imazapic applied POST alone or with acifluoren, diclosulam, or 2,4-DB was compared. In a final experiment, yellow nutsedge control by imazapic alone and with the fungicides azoxystrobin, chlorothalonil, pyraclostrobin, and tebuconazole was compared. Large crabgrass was controlled more effectively by imazapic POST than diclosulam PRE. Common lambsquarters, common ragweed, and eclipta were controlled more effectively by diclosulam PRE than imazapic POST. Nodding spurge was controlled similarly by both herbicides. Few differences in control were noted when comparing imazapic rates after diclosulam PRE. Applying either diclosulam PRE or imazapic POST alone or in combination increased peanut yield over nontreated peanut in five of six experiments. Few differences in pod yield were noted when comparing imazapic rates. Acifluorfen, diclosulam, and 2,4-DB did not affect entireleaf morningglory, large crabgrass, nodding spurge, pitted morningglory, and yellow nutsedge control by imazapic. Eclipta control by coapplication of imazapic and diclosulam exceeded control by imazapic alone. The fungicides azoxystrobin, chlorothalonil, pyraclostrobin, and tebuconazole did not affect yellow nutsedge control by imazapic.

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Early Season Broadleaf Weed Control in Onion

HortScience ◽

10.21273/hortsci.41.4.971d ◽

2006 ◽

Vol 41 (4) ◽

pp. 971D-972

Author(s):

Harlene M. Hatterman-Valenti ◽

Carrie E. Schumacher ◽

Collin P. Auwarter ◽

Paul E. Hendrickson

Keyword(s):

Weed Control ◽

Chenopodium Album ◽

Field Studies ◽

Amaranthus Retroflexus ◽

High Rate ◽

Early Season ◽

Common Lambsquarters ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Residual Control

Field studies were conducted at Absaraka, Carrington, and Oakes, N.D., in 2005 to evaluate early season broadleaf weed control and onion (Allium cepa L.) injury with herbicides applied preemergence to the crop. DCPA is a common preemergence herbicide used in onion. However, DCPA can be uneconomical in most high-weed situations, or the usage may be restricted due to possible groundwater contamination. Potential substitutes evaluated were bromoxynil, dimethenamid-P, and pendimethalin. Main broadleaf weeds were redroot pigweed (Amaranthus retroflexus L.) and common lambsquarters (Chenopodium album L.). In general, all herbicides, except bromoxynil, provided acceptable broadleaf weed control 4 weeks after treatment. The highest herbicide rate provided greater weed control compared with the lowest rate for each herbicide. However, onion height was also reduced with the highest herbicide rate. In addition, the two highest rates of dimethenamid-P reduced the onion stand compared with the untreated. A postemergence application of bromoxynil + oxyfluorfen + pendimethalin to onion at the four- to five-leaf stage controlled the few broadleaf weeds that escaped the preemergence treatments and provided residual control of mid- and late-season germinating broadleaf weeds at two of the three locations. Intense germination of redroot pigweed during July at the Oakes location reduced onion yield with all treatments compared with the hand-weeded check. In contrast, total onion yields with all herbicide treatments except the high rate of dimethenamid-P were similar to the hand-weeded check at Absaraka and Carrington.

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Influence of application timing and herbicide rate on the efficacy of tolpyralate plus atrazine

Weed Technology ◽

10.1017/wet.2019.25 ◽

2019 ◽

Vol 33 (03) ◽

pp. 448-458 ◽

Cited By ~ 1

Author(s):

Brendan A. Metzger ◽

Nader Soltani ◽

Alan J. Raeder ◽

David C. Hooker ◽

Darren E. Robinson ◽

...

Keyword(s):

Weed Management ◽

Field Experiments ◽

Integrated Weed Management ◽

Herbicide Application ◽

Weed Species ◽

Common Ragweed ◽

Application Timing ◽

Common Lambsquarters ◽

Green Foxtail ◽

Equivalent Control

AbstractEffective POST herbicides and herbicide mixtures are key components of integrated weed management in corn; however, herbicides vary in their efficacy based on application timing. Six field experiments were conducted over 2 yr (2017–2018) in southwestern Ontario, Canada, to determine the effects of herbicide application timing and rate on the efficacy of tolpyralate, a new 4-hydroxyphenyl pyruvate dioxygenase inhibitor. Tolpyralate at 15, 30, or 40 g ai ha−1 in combination with atrazine at 500 or 1,000 g ai ha−1 was applied PRE, early POST, mid-POST, or late POST. Tolpyralate + atrazine at rates ≥30 + 1,000 g ha−1 provided equivalent control of common lambsquarters and Powell amaranth applied PRE or POST, whereas no rate applied PRE controlled common ragweed, velvetleaf, barnyardgrass, or green foxtail. Common ragweed, common lambsquarters, velvetleaf, and Powell amaranth were controlled equally regardless of POST timing. In contrast, control of barnyardgrass and green foxtail declined when herbicide application was delayed to the late-POST timing, irrespective of herbicide rate. Similarly, corn grain yield declined within each tolpyralate + atrazine rate when herbicide applications were delayed to late-POST timing. Overall, the results of this study indicate that several monocot and dicot weed species can be controlled with tolpyralate + atrazine with an early to mid-POST herbicide application timing, before weeds reach 30 cm in height, and Powell amaranth and common lambsquarters can also be controlled PRE. Additionally, this study provides further evidence highlighting the importance of effective, early-season weed control in corn.

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Tropic Croton (Croton glandulosus) Control in Peanut (Arachis hypogaea)

Weed Technology ◽

10.1017/s0890037x0003387x ◽

1991 ◽

Vol 5 (4) ◽

pp. 795-798 ◽

Cited By ~ 12

Author(s):

John W. Wilcut

Keyword(s):

Arachis Hypogaea ◽

Field Studies ◽

Common Ragweed ◽

Application Timing ◽

Common Lambsquarters ◽

Net Returns ◽

Herbicide Treatments ◽

The Common

Field studies in 1988 and 1989 evaluated POST herbicides alone and in tank-mixtures for tropic croton control in peanut. Acifluorfen + 2,4-DB, acifluorfen + bentazon, acifluorfen + bentazon + 2,4-DB controlled > 90% of tropic croton when applied at 2 or 4 wk after crop emergence. Paraquat + bentazon controlled 55% at 2 wk and 24% at 4 wk after crop emergence. Imazethapyr and imazethapyr + 2,4-DB controlled < 24% tropic croton at either 2 or 4 wk after crop emergence. Acifluorfen + 2,4-DB, acifluorfen + bentazon, and acifluorfen + bentazon + 2,4-DB controlled at least 90% of the common lambsquarters, common ragweed, and morningglory species. Greatest yields and net returns were obtained with acifluorfen + bentazon + 2,4-DB applied 2 wk after crop emergence. Yields were higher with acifluorfen + bentazon + 2,4-DB and imazethapyr applied at 2 wk after crop emergence than at 4 wk after crop emergence. All other herbicide treatments provided equivalent yields among application timings. Only acifluorfen + 2,4-DB provided equivalent net returns at either application timing. All other herbicide treatments provided lower net returns with applications made at 4 wk than at 2 wk after crop emergence.

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Weed Control in Glyphosate-Resistant Corn as Affected by Preemergence Herbicide and Timing of Postemergence Herbicide Application

Weed Technology ◽

10.1614/wt-04-288r.1 ◽

2006 ◽

Vol 20 (3) ◽

pp. 564-570 ◽

Cited By ~ 23

Author(s):

Robert G. Parker ◽

Alan C. York ◽

David L. Jordan

Keyword(s):

Grain Yield ◽

Weed Control ◽

Field Studies ◽

Herbicide Application ◽

Application Timing ◽

Common Lambsquarters ◽

Herbicide Treatments ◽

Prickly Sida ◽

Smooth Pigweed ◽

Or Applications

Field studies were conducted at three locations during both 2002 and 2003 to evaluate weed control and response of glyphosate-resistant (GR) corn to glyphosate or nicosulfuron plus atrazine applied POST at three application timings with and without alachlor plus atrazine applied PRE. The POST herbicides were applied timely (5- to 9-cm weeds) or applications were delayed 1 or 2 wk. All treatments, except the weedy check, were followed by glyphosate postemergence-directed (PDIR) 4 wk after the timely POST application. Common lambsquarters, common ragweed, Palmer amaranth, prickly sida, and smooth pigweed were controlled at least 94% regardless of PRE or POST treatments. Large crabgrass and fall panicum were controlled at least 96% by glyphosate regardless of PRE herbicide or POST application timing. In contrast, control by nicosulfuron plus atrazine POST in the absence of PRE herbicide decreased as application was delayed. Sicklepod was controlled at least 94% when POST herbicides were applied timely, but control by both POST herbicide treatments decreased with delayed application regardless of PRE herbicide. Tall morningglory was controlled 93% or greater by POST herbicides applied timely. Control by both POST herbicide treatments decreased as application was delayed, with glyphosate being affected more by timing than nicosulfuron plus atrazine. Corn grain yield was similar with glyphosate and nicosulfuron plus atrazine. Yield was unaffected by POST application timing when PRE herbicides were included. Without PRE herbicide, grain yield decreased as POST herbicide application was delayed.

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