Weed Management in Glyphosate-Resistant Corn with Glyphosate, Halosulfuron, and Mesotrione

2004 ◽  
Vol 18 (3) ◽  
pp. 826-834 ◽  
Author(s):  
Walter E. Thomas ◽  
Ian C. Burke ◽  
John W. Wilcut

Four field studies were conducted at the Peanut Belt Research Station near Lewiston Woodville, NC, in 2000, 2001, and 2002 to evaluate crop tolerance, weed control, grain yield, and net returns in glyphosate-resistant corn with various herbicide systems. Preemergence (PRE) treatment options included no herbicide, atrazine at 1.12 kg ai/ha, or atrazine plus metolachlor at 1.68 kg ai/ha. Postemergence (POST) treatment options included glyphosate at 1.12 kg ai/ha as either the isopropylamine salt or the diammonium salt, either alone or in mixtures with mesotrione at 105 g ai/ha plus crop oil concentrate at 1% (v/v) or halosulfuron at 53 g ai/ha plus 0.25% (v/v) nonionic surfactant. All response variables were independent of glyphosate formulation. Addition of metolachlor to atrazine PRE improved large crabgrass and goosegrass control but did not always improve Texas panicum control. POST control of these annual grasses was similar with glyphosate alone or in mixture with halosulfuron or mesotrione. Glyphosate POST controlled common lambsquarters and common ragweed 89 and 93%, respectively. Glyphosate plus halosulfuron POST provided more effective yellow nutsedge control than glyphosate POST. Atrazine PRE or atrazine plus metolachlor PRE followed by any glyphosate POST treatment controlledIpomoeaspp. at least 93%. Glyphosate plus mesotrione in total POST systems always provided greater control ofIpomoeaspp. than glyphosate alone. The highest yielding treatments always included glyphosate POST, either with or without a PRE herbicide treatment. Similarly, systems that included any glyphosate POST treatment had the highest net returns.

2004 ◽  
Vol 18 (4) ◽  
pp. 1049-1057 ◽  
Author(s):  
Walter E. Thomas ◽  
Ian C. Burke ◽  
John W. Wilcut

Three field studies were conducted at Lewiston Woodville, NC, in 2001 and 2002 to evaluate crop tolerance, weed control, grain yield, and net returns in glyphosate-resistant corn with various herbicide systems. Crop injury, weed control, and grain yield were not influenced by glyphosate formulation. Atrazine preemergence (PRE) and atrazine plus metolachlor PRE, averaged over postemergence (POST) systems, controlled Texas panicum at least 80 and 87%, respectively. Sequential glyphosate applications (early postemergence [EPOST] followed by [fb] POST) provided at least 99% control of Texas panicum compared with at least 86 and 88% control with glyphosate EPOST and glyphosate plus halosulfuron EPOST, respectively. Atrazine plus metolachlor PRE fb any glyphosate system controlled large crabgrass and goosegrass 89 to 100% and 94 to 100%, respectively. Sequential glyphosate treatments controlled large crabgrass and goosegrass at least 99 and 95%, respectively. Regardless of PRE system, glyphosate plus halosulfuron EPOST and sequential applications of glyphosate controlled common ragweed and common lambsquarters at least 99%, whereas glyphosate EPOST alone provided at least 88 and 96% control, respectively. Glyphosate plus halosulfuron EPOST and glyphosate sequentially controlled yellow nutsedge similarly and more consistently than glyphosate EPOST. Regardless of PRE treatment, sequential glyphosate applications provided at least 98% control of entireleaf and pitted morningglory, whereas glyphosate EPOST controlled at least 64 and 62%, respectively. Glyphosate EPOST and the sequential glyphosate EPOST fb POST systems yielded similarly at all three locations. Net returns were highest at all three locations with the glyphosate sequential system, with similar net returns obtained with glyphosate EPOST and glyphosate plus halosulfuron EPOST at two and one locations, respectively.


2006 ◽  
Vol 20 (1) ◽  
pp. 232-241 ◽  
Author(s):  
Scott B. Clewis ◽  
John W. Wilcut ◽  
Dunk Porterfield

Five studies were conducted at Clayton, Rocky Mount, and Lewiston-Woodville, NC, in 2001 and 2002, to evaluate weed management, crop tolerance, and yield in strip- and conventional-tillage glyphosate-resistant cotton. Cotton was treated with two glyphosate formulations; glyphosate-IP (isopropylamine salt) or glyphosate-TM (trimethylsulfonium salt), early postemergence (EPOST) alone or in a mixture withS-metolachlor. Early season cotton injury was minimal (3%) with either glyphosate formulation alone or in mixture withS-metolachlor. Weed control and cotton yields were similar for both glyphosate formulations. The addition ofS-metolachlor to either glyphosate formulation increased control of broadleaf signalgrass, goosegrass, large crabgrass, and yellow foxtail 14 to 43 percentage points compared with control by glyphosate alone.S-metolachlor was not beneficial for late-season control of entireleaf morningglory, jimsonweed, pitted morningglory, or yellow nutsedge. The addition ofS-metolachlor to either glyphosate formulation increased control of common lambsquarters, common ragweed, Palmer amaranth, smooth pigweed, and velvetleaf 6 to 46 percentage points. The addition of a late postemergence-directed (LAYBY) treatment of prometryn plus MSMA increased control to greater than 95% for all weed species regardless of EPOST treatment, and control was similar with or withoutS-metolachlor EPOST. Cotton lint yield was increased 220 kg/ha with the addition ofS-metolachlor to either glyphosate formulation compared with yield from glyphosate alone. The addition of the LAYBY treatment increased yields 250 and 380 kg/ha for glyphosate plusS-metolachlor and glyphosate systems, respectively.S-metolachlor residual activity allowed for an extended window for more effective LAYBY application to smaller weed seedlings instead of weeds that were possibly larger and harder to control.


1990 ◽  
Vol 4 (2) ◽  
pp. 239-244 ◽  
Author(s):  
John W. Wilcut ◽  
Glenn R. Wehtje ◽  
T. Vint Hicks ◽  
Tracy A. Cole

Field studies were conducted from 1985 to 1987 to evaluate postemergence herbicide systems with preemergence systems to control Texas panicum, Florida beggarweed, sicklepod, and pitted morningglory in peanuts. Adding paraquat at 0.14 kg ai/ha to postemergence herbicide systems reduced fresh weight of Florida beggarweed 92% (18% increase over the same systems without paraquat), sicklepod 95% (21% increase), and pitted morningglory 95% (11% increase). Herbicide systems containing paraquat improved peanut yields by 230 kg/ha and net returns by $52/ha over herbicide systems not containing paraquat. Fluazifop-P and sethoxydim systems reduced Texas panicum fresh weight (at least 96%) more than a preemergence system (92% reduction) that used benefin applied preplant incorporated and alachlor plus naptalam and dinoseb applied at cracking (GC) or a postemergence system that used alachlor and naptalam plus dinoseb GC and paraquat applied early postemergence (86% reduction). Systems containing fluazifop-P provided greater yields (4190 kg/ha) and net returns ($383/ha) than systems containing sethoxydim (4010 kg/ha, $305/ha) when averaged across all rates of application.


Weed Science ◽  
1998 ◽  
Vol 46 (6) ◽  
pp. 698-702 ◽  
Author(s):  
W. Carroll Johnson ◽  
Benjamin G. Mullinix

Field studies were conducted from 1995 to 1997 near Tifton, GA, to determine the benefits of stale seedbed weed control in cucumber. Three stale seedbed management systems—(1) power till stale seedbeds twice (2 ×), (2) glyphosate application immediately after planting, and (3) combination system of stale seedbeds power tilled once 2 wk prior to planting followed by glyphosate application immediately after planting cucumber—were evaluated as main plots. Subplots were weed management systems after planting cucumber: intensive, basic, and cultivation alone. Weed densities were generally greater in 1996 and 1997 than in 1995. Yellow nutsedge was the overall predominant species in 1995 (46 plants m−2), with Florida pusley being the predominant species in 1996 and 1997, at 80 and 124 plants m−2, respectively. Generally, stale seedbeds shallow tilled 2 × had fewer weeds and greater cucumber yields than stale seedbeds treated with glyphosate. Glyphosate did not adequately control emerged Florida pusley on stale seedbeds, resulting in reduced cucumber yield. Clomazone preemergence and bentazon/halosulfuron postemergence were used for broadleaf weed control in the intensive weed management system. These herbicides injured cucumber plants, delayed maturity, and reduced yield. Based on our results, stale seedbeds shallow tilled 2 × can be integrated into cucumber production and provide effective cultural weed control. Furthermore, these systems will replace the need for potentially injurious herbicides.


Weed Science ◽  
2003 ◽  
Vol 51 (6) ◽  
pp. 1002-1009 ◽  
Author(s):  
Dunk Porterfield ◽  
John W. Wilcut ◽  
Jerry W. Wells ◽  
Scott B. Clewis

Field studies conducted at three locations in North Carolina in 1998 and 1999 evaluated crop tolerance, weed control, and yield with CGA-362622 alone and in combination with various weed management systems in transgenic and nontransgenic cotton systems. The herbicide systems used bromoxynil, CGA-362622, glyphosate, and pyrithiobac applied alone early postemergence (EPOST) or mixtures of CGA-362622 plus bromoxynil, glyphosate, or pyrithiobac applied EPOST. Trifluralin preplant incorporated followed by (fb) fluometuron preemergence (PRE) alone or fb a late POST–directed (LAYBY) treatment of prometryn plus MSMA controlled all the weed species present less than 90%. Herbicide systems that included soil-applied and LAYBY herbicides plus glyphosate EPOST or mixtures of CGA-362622 EPOST plus bromoxynil, glyphosate, or pyrithiobac controlled broadleaf signalgrass, entireleaf morningglory, large crabgrass, Palmer amaranth, prickly sida, sicklepod, and smooth pigweed at least 90%. Only cotton treated with these herbicide systems yielded equivalent to the weed-free check for each cultivar. Bromoxynil systems did not control Palmer amaranth and sicklepod, pyrithiobac systems did not control sicklepod, and CGA-362622 systems did not control prickly sida.


2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0021
Author(s):  
Takaaki Hirano ◽  
Yui Akiyama ◽  
Tomoko Karube ◽  
Naoki Haraguchi ◽  
Hisateru Niki ◽  
...  

Category: Ankle Arthritis Introduction/Purpose: Ankle arthrodesis (fusion) for the treatment of osteoarthritis of the ankle (OA) was reported to have good therapeutic results; however, this has not been compared with conservative treatment. At this conference last year, brace treatment using an ankle-foot orthosis, Hiflex Foot Gear (HFG), was also reported to have good therapeutic results, which allows for slight mobility in the ankle joint while providing appropriate level of support for the ankle joint. On this occasion, the therapeutic results of brace treatment and fusion were compared, and treatment options for OA were examined. Methods: Subjects included nine cases and ten feet in a group that was diagnosed with stage IIIb OA or worse according to the Takakura Classification and were treated with HFG (mean age of 70.6 years, mean course observation period of 8.4 months) and nine cases and ten feet in a group that was treated with fusion for the same diagnosis (mean age of 58.1 years, mean course observation period of 25.5 months). The pre-treatment and post-treatment physician-initiated objective evaluation by the Japanese Society for Surgery of the Foot scale (JSSF scale) and patient-reported subjective evaluation by the Japanese Orthopaedic Association/ the Japanese Society for Surgery of the Foot, and subscales of Self-Administered Foot Evaluation Questionnaire (SAFE-Q) were examined, and improvements in each score in two groups were compared (post-treatment vs pre-treatment) by an unpaired t-test. The validity and reliability of JSSF scale and SAFE-Q have been established by psychometric verification Results: The improvement after the treatment for the HFG group and the fusion group was observed. JSSF scores were 16.1 (p < 0.001) and 35.5 (p < 0.001), respectively, and pain and pain-related scores in the SAFE-Q were 20.8 (p = 0.021) and 35.4 (p < 0.001), respectively. Physical function and daily living were 12.8 (p < 0.001) and 18.6 (p = 0.007), respectively, while social functioning scores were 18.0 (p = 0.001) and 32.8 (p = 0.001), respectively. The JSSF score for both groups was significantly improved. In SAFE-Q, physical function and daily living improved significantly in the HFG group, while pain and pain-related improved significantly in the fusion group.


Author(s):  
S. P. Singh ◽  
R. S. Yadav ◽  
Amit Kumawat ◽  
R. R. Jakhar

A field experiment was conducted at Research Farm of Agricultural Research Station, Swami Keshwanand Rajasthan Agricultural University, Bikaner during three consecutive kharif season of 2013, 2014 and 2015. The experiment comprising ten weeds control treatments consisting of pendamethalin 1000 g/ha (PE), imazethapyr 50g/ha (3-4 leaf stage of crop), imazethapyr 70g/ha (3-4 leaf stage of crop), pendamethalin + imazethapyr 800g/ha (PE), pendamethalin + imazethapyr 900g/ha (PE), pendamethalin + imazethapyr 1000g/ha (PE), imazethapyr + imazamox 60g/ha (3-4 leaf stage of crop), imazethapyr + imazamox 70g/ha (3-4 leaf stage of crop), 2 hand weeding at 20 and 40 DAS and weedy check in randomized block design (RBD) with three replications. Two hand weeding at 20 and 40 DAS was found most effective to control weeds in greengram and recorded lowest weed count and weed dry matter of both broad leaved and grassy weeds. It was also recorded significantly highest branches/pant, leaf area index, total chlorophyll, protein content in seed, pods/plant, seeds/pod and seed, straw and biological yield over other treatments. Among different herbicides, pendamethalin + imazethapyr 800g recorded significantly higher net returns (31350/ha) and B:C ratio (2.70).


2019 ◽  
Vol 33 (03) ◽  
pp. 426-430 ◽  
Author(s):  
Matthew J. Osterholt ◽  
Eric P. Webster ◽  
David C. Blouin ◽  
Benjamin M. McKnight

AbstractA study was conducted at the Louisiana State University Agricultural Center’s H. Rouse Caffey Rice Research Station in 2017 and 2018 to evaluate a prepackaged mixture of clomazone plus pendimethalin applied delayed preemergence (DPRE) or POST within an herbicide residual overlay with saflufenacil, clomazone, or quinclorac. POST applications included penoxsulam or halosulfuron in combination with the second residual application. No differences were observed in barnyardgrass control (92% to 98%) at 14 days after treatment (DAT). At 42 DAT, barnyardgrass treated with clomazone plus pendimethalin in combination with either clomazone or quinclorac at either timing was controlled 95% to 96%. However, when saflufenacil was applied PRE, regardless of the POST herbicide or when saflufenacil was applied POST with halosulfuron, barnyardgrass control was reduced to 78% to 81%, compared with 95% to 96% with the control with all other residual combinations. Yellow nutsedge and rice flatsedge control increased when treated with halosulfuron compared with penoxsulam across all evaluation dates. At 28 and 42 DAT, texasweed treated with saflufenacil PRE, regardless of POST applications, was controlled 83% and 87%, respectively, and this was greater control than provided by clomazone or quinclorac applied PRE regardless of POST herbicide program.


Weed Science ◽  
1970 ◽  
Vol 18 (3) ◽  
pp. 393-395 ◽  
Author(s):  
P. E. Keeley ◽  
R. J. Thullen ◽  
J. H. Miller

Studies were conducted on and in the vicinity of the U. S. Cotton Research Station at Shafter, California, to evaluate the prevalence of the insect Bactra verutana Zeller (Olethreutidae) and its potential for injury to yellow nutsedge (Cyperus esculentus L.). Field surveys during August 1966, and August and October 1967 revealed many infested yellow nutsedge plants. Other field studies indicated that the insect may significantly suppress the growth of yellow nutsedge, providing that the insect infestation is early, sufficiently severe, and present on both parent and subsequently emerging vegetative plants. Greenhouse studies further revealed that severely infested plants may survive to produce numerous vegetative plants and tubers. While Bactra verutana Zeller damaged yellow nutsedge plants late in the season, the absence of early infestation limited its usefulness as a biological control agent.


2008 ◽  
Vol 22 (4) ◽  
pp. 571-579 ◽  
Author(s):  
Ian C. Burke ◽  
Walter E. Thomas ◽  
Jayla R. Allen ◽  
Jim Collins ◽  
John W. Wilcut

Experiments were conducted at three North Carolina research stations in 2003 to evaluate weed control and corn yield in glyphosate-resistant, glufosinate-resistant, imidazolinone-tolerant, and conventional corn weed management systems. Late-season control of common lambsquarters, large crabgrass, and yellow nutsedge increased with metolachlor PRE compared with no PRE herbicide treatment. Common lambsquarters, pitted morningglory, entireleaf morningglory, spurred anoda, and tropic croton control was improved by a single early POST (EPOST) application regardless of herbicide system. Control of common lambsquarters, pitted morningglory, entireleaf morningglory, and spurred anoda was similar for glyphosate and glufosinate systems for each POST over-the-top (POT) herbicide system. A single EPOST application of imazethapyr plus imazapyr to imidazolinone-tolerant corn controlled common lambsquarters, pitted morningglory, entireleaf morningglory, and spurred anoda and was better than a single EPOST application of glyphosate, glufosinate, or nicosulfuron. Tropic croton was controlled ≥ 95% with glufosinate or glyphosate, applied once or twice, or in mixture with metolachlor. A single EPOST application of imazethapyr plus imazapyr or nicosulfuron did not control tropic croton. Common lambsquarters, entireleaf morningglory, large crabgrass, Palmer amaranth, and yellow nutsedge control was greater with a late-POST–directed (LAYBY) of ametryn than no LAYBY. Systems that did not include a POT herbicide system had the lowest percentage in the weed-free yield and the lowest yield. Treatments that included a POT system with or without a PRE treatment of metolachlor yielded within 5% of the weed-free treatment, regardless of herbicide system.


Sign in / Sign up

Export Citation Format

Share Document