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Author : Kenneth L. Smith
Publisher :
ISBN 13 :
Total Pages : 6 pages
Book Rating : 4.:/5 (51 download)
Download or read book Glyphosate-resistant Palmer Amaranth and Ryegrass Management written by Kenneth L. Smith and published by . This book was released on 2009 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Ilias Travlos
Publisher : Frontiers Media SA
ISBN 13 : 2889660060
Total Pages : 329 pages
Book Rating : 4.8/5 (896 download)
Download or read book Herbicide Resistance in Weeds: Early Detection, Mechanisms, Dispersal, New Insights and Management Issues written by Ilias Travlos and published by Frontiers Media SA. This book was released on 2020-10-28 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.
Author : Matthew Scott Wiggins
Publisher :
ISBN 13 :
Total Pages : 133 pages
Book Rating : 4.:/5 (119 download)
Download or read book Integration and Management of Winter-annual Cover Crops and Herbicides to Control Glyphosate-resistant Palmer Amaranth (Amaranthus Palmeri S. Wats) written by Matthew Scott Wiggins and published by . This book was released on 2014 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this research was to evaluate the integration of high residue winter-annual cover crops with herbicides, both preemergence and postemergence, to control glyphosate-resistant Palmer amaranth. The results of these trials indicated that winter-annual cover crops improved early-season weed suppression. However, cover crops alone or as part of an integrated weed management system including only preemergence or only postemergence herbicides was not sufficient to control of glyphosate-resistant Palmer amaranth. Therefore, winter-annual cover crops should be used in conjunction with existing weed control tactics to achieve adequate glyphosate-resistant Palmer amaranth control, where applicable.
Author : Vijay K. Nandula
Publisher : John Wiley & Sons
ISBN 13 : 1118043545
Total Pages : 258 pages
Book Rating : 4.1/5 (18 download)
Download or read book Glyphosate Resistance in Crops and Weeds written by Vijay K. Nandula and published by John Wiley & Sons. This book was released on 2010-12-28 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: New technologies are becoming available for managing glyphosate resistant (GR) weeds and reducing their spread. GR crop technology has revolutionized crop production in the developed world and the benefits are gradually spilling over to the developing world. In order to sustain an effective, environmentally safe herbicide such as glyphosate and the GR crop technology well in to the future, it is imperative that the issue of GR weeds be comprehensively understood. This book provides such an essential, up-to-date source of information on glyphosate resistance for researchers, extension workers, land managers, government personnel, and other decision makers. Provides comprehensive coverage of the intensely studied topic of glyphosate resistant (GR) in crops Details the development of glyphosate resistance and how to detect and manage the problem in crops Helps standardize global approaches to glyphosate resistance Encompasses interdisciplinary approaches in chemistry, weed science, biochemistry, plant physiology, plant biotechnology, genetics, ecology Includes a chapter on economic analysis of GR impact on crops
Download or read book Distribution, Biology, and Management of Glyphosate-resistant Palmer Amaranth in North Carolina written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The introduction of glyphosate-resistant (GR) crops allowed for the topical applications of the herbicide glyphosate. This herbicide revolutionized weed control and crop management. Widespread adoption of this technology and extensive use of glyphosate led to intense selection pressure for evolution of GR weeds. In 2005, GR Palmer amaranth was suspected in North Carolina. A survey detected GR populations in 49 of 290 fields sampled. ALS-inhibitor resistance was also detected in 52 fields. Five fields had populations exhibiting multiple resistance to both glyphosate and ALS-inhibitors. Experiments were conducted to determine the resistance mechanism of GR Palmer amaranth. A GR biotype exhibited a 20-fold level of resistance compared to a glyphosate-susceptible (GS) biotype. Shikimate accumulated in GS but not GR plants after glyphosate application. Maximum absorption was observed by 12 hours after treatment (HAT), and was similar among biotypes except at 6 HAT, where GS plants absorbed 67% more than GR plants. Distribution of 14C was similar among biotypes in (42%), above (30%), and below (22%) the treated leaf and in roots (6%). This work did not lead to a suggestion a resistance mechanism. Field experiments were conducted to develop management strategies for GR Palmer amaranth in cotton. One evaluated residual control of Palmer amaranth by various herbicides. Of herbicides typically applied PRE or pre-plant, fomesafen, flumioxazin, and pyrithiobac were most effective. Pyrithiobac and S-metolachlor were the most effective postemergence (POST) herbicides. Flumioxazin and prometryn plus trifloxysulfuron were the most effective options for postemergence-directed applications. Integration of these herbicides into glyphosate-based systems could increase Palmer amaranth control. An experiment was conducted to evaluate PRE herbicides in a season-long system. All PRE herbicides increased late-season control. Among individual herbicides, fomesafen and pyrithiobac were most e.
Author : Shawn Thomas McDonald
Publisher :
ISBN 13 :
Total Pages : 108 pages
Book Rating : 4.:/5 (126 download)
Download or read book Management of Glyphosate-resistant Palmer Amaranth (amaranth Palmeri S. Watson) in Dicamba/glyphosate-resistant Soybean written by Shawn Thomas McDonald and published by . This book was released on 2021 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: While not a historically problematic weed in Nebraska, Palmer amaranth has become increasingly problematic in many agronomic cropping systems. Throughout the state, several cohorts of Palmer amaranth have been found resistant to several different sites of action. Of major concern is a population found resistant to glyphosate the most common post-emergence herbicide in Nebraska. As chemical control methods are the most common forms of weed control throughout the state methods alternatives or enhancements are highly desired. Two field experiments were conducted in 2018 and 2019 at a grower's field near Carleton, Nebraska with the objectives to evaluate the effects of row spacing and herbicide programs and separately analyze the effect of overlapping residual herbicides on control of glyphosate-resistant (GR) Palmer amaranth, gross profit margin, and benefit-cost ratios of these herbicide programs. Evaluation of the effect on row spacing found no significant effect of narrowing row spacing on control, density, or biomass reduction of GR Palmer amaranth across all herbicide programs. Herbicide program had a higher impact on GR Palmer amaranth control with all PRE fb EPOST except dicamba + chlorimuron/flumioxazin followed by dicamba and all PRE fb EPOST+RH providing greater than 85% control from 14 d after EPOST (DAEPOST) to 36 DAEPOST. Evaluation of overlapping residual herbicides on management of GR Palmer amaranth found that flumioxazin/pyroxasulfone/metribuzin provided 78% to 82% control from 14 DAEPOST to 70 DAEPOST in 2018 and 94% to 98% in 2019. Addition of dicamba + acetochlor EPOST to flumioxazin/pyroxasulfone/metribuzin provided 83% to 96% from 14 DAEPOST to 70 DAEPOST in 2018 and 99% in 2019. As the adoption of new application technologies, herbicide-resistant crops, and alternative weed control methods change with the times, surveys provide insight into changes in weed dynamics and crop production over time. Conducting multiple surveys over the course of several years provides a vital framework in developing future research and extension outreach. During the winter of 2019-2020, a survey of Nebraska stakeholders was carried to quantify crop production, weed control, and management practices throughout the state. In order of importance, Palmer amaranth, horseweed, common waterhemp, kochia, and giant ragweed were ranked the most problematic weeds statewide. Based on survey responses, 27% of respondents, cited integrated weed management systems as the primary concern for future research and extension outreach for the state of Nebraska.
Author : Johnson Harris Hughes
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)
Download or read book Evaluation of Italian Ryegrass and Palmer Amaranth Control in Mississippi written by Johnson Harris Hughes and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass is a problematic weed in Mississippi corn production due to the development and proliferation of glyphosate resistance. Studies were conducted to assess Italian ryegrass control prior to planting using herbicides. Effects of fall and spring applied burndown herbicide applications for Italian ryegrass control and subsequent corn grain yield were investigated at the R.R. Foil PSRC in Starkville, MS, at the Coastal Plain Experiment Station in Newton, MS, and the Black Belt Experiment Station in Brooksville, MS on soil textures ranging from sandy loam to silt clay loam. A fall preemergence (PRE) application of S-metolachlor + metribuzin followed by paraquat in the spring provided 99% Italian ryegrass control 28 days after paraquat application. Four spring burndown treatments provided Italian ryegrass control similar to that observed following application of the fall PRE application followed by paraquat in the spring. Applications clethodim + glufosinate + paraquat + dimethenamid-P; clethodim + glufosinate + paraquat + S-metolachlor; clethodim + paraquat + dimethenamid-P; and clethodim + oxyfluorfen + paraquat + S-metolachlor resulted in similar levels of Italian ryegrass control at 96%, 98%, 94%, and 99%, respectively. Corn yield following the fall PRE followed by spring paraquat application was 10,687 kg ha-1. Corn yield following clethodim + paraquat + dimethenamid-P as well as clethodim + oxyfluorfen + paraquat + S-metolachlor applied in the spring resulted in similar corn grain yield to that following the fall PRE followed by spring paraquat application at 9,649 kg ha-1 and 9,567 kg ha-1, respectively. Spring burndown herbicide treatments could be used to control Italian ryegrass while producing similar corn yield to the standard fall herbicide followed by paraquat application in the spring.
Author : Drake Copeland
Publisher :
ISBN 13 :
Total Pages : 147 pages
Book Rating : 4.:/5 (112 download)
Download or read book Characterization and Management of PPO and Glyphosate Resistant Palmer Amaranth written by Drake Copeland and published by . This book was released on 2018 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research was conducted from the fall of 2016 to the fall of 2018 to characterize and manage PPO- and glyphosate-resistant Palmer amaranth (Amaranthus palmeri S. Wats). Studies included a multi-county survey to determine the prevalence of PPO-resistant Palmer amaranth biotypes and the PPX2 mutations that confer PPO resistance, an in-field evaluation of control of PPO-resistant and PPO-susceptible Palmer amaranth populations with herbicide treatments applied at either sunrise or midday, and field studies that evaluated cover crop termination for control of Palmer amaranth in Roundup Ready Xtend® and Liberty Link® soybean systems [(Glycine max (L.) Merr.]. Results from this research indicate that PPO-resistant Palmer amaranth infests roughly 80% of west Tennessee fields, at least two herbicides with different, effective sites of action should be applied timely for POST herbicidal control of PPO-resistant Palmer amaranth, and that delaying cover crop termination in both Roundup Ready Xtend® and Liberty Link® soybeans can effectively reduce in-season POST applications and maximize Palmer amaranth control if the correct residual herbicide is included at planting timing.
Author : Jared Ross Whitaker
Publisher :
ISBN 13 :
Total Pages : 231 pages
Book Rating : 4.:/5 (319 download)
Download or read book Distribution, Biology, and Management of Glyphosate-resistant Palmer Amaranth in North Carolina written by Jared Ross Whitaker and published by . This book was released on 2009 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: Palmer amaranth, herbicide resistance, glyphosate.
Author : Whitney Desiree Crow
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (133 download)
Download or read book Glyphosate Resistant Palmer Amaranth (amaranthus Palmeri) Management Late-season and Post-harvest in Corn Production Systems written by Whitney Desiree Crow and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this research were to evaluate control options for glyphosate resistant (GR) Palmer amaranth (Amaranthus palmeri) latelate-season in corn systems and POST-harvest for the prevention of seed production. Our results determined that the best late-season control methods were treatments tank-mixed with dicamba plus diflufenzopyr. These tank-mixtures improved control from 10 to 46% [percent] over treatments without the dicamba premix. Tankmixtures with dicamba plus diflufenzopyr that provided weed control > [greater than] 96% 28 DAA included s-metolachlor plus glyphosate plus mesotrione and tembotrione plus thiencarbazone. For the prevention of POST-harvest GR palmer amaranth seed production, our results determined that paraquat provides excellent initial control of existing vegetation but regrowth can occur from larger plants. The addition of a residual herbicide may aid in controlling regrowth as well as preventing plant germination. All treatments provided enough control for the prevention of seed production. Through implementation of POST-harvest management practices, 1200 seed per m2 [meter squared] was prevented from replenishing the soil seed bank. There were no adverse affects on wheat yield. From these results, we can conclude that when practicing POST only weed management strategies, application timing is vital for the prevention of corn loss and that implementation of late-season weed management programs can effectively reduce weed seed rain, therefore reducing weed seed bank densities.
Author : Parminder S. Chahal
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (115 download)
Download or read book Herbicide-Resistant Palmer Amaranth (Amaranthus Palmeri S. Wats.) in the United States - Mechanisms of Resistance, Impact, and Management written by Parminder S. Chahal and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Palmer amaranth, a dioecious summer annual species, is one of the most troublesome weeds in the agronomic crop production systems in the United States. In the last two decades, continuous reliance on herbicide(s) with the same mode of action as the sole weed management strategy has resulted in the evolution of herbicide-resistant (HR) weeds, including Palmer amaranth. By 2015, Palmer amaranth biotypes had been confirmed resistant to acetolactate synthase (ALS)-inhibitors, dinitroanilines, glyphosate, hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitors, and triazine herbicides in some parts of the United States along with multiple HR biotypes. Mechanisms of herbicide-resistance in Palmer amaranth are discussed in this chapter. Preplant herbicide options including glufosinate, 2,4-D, and dicamba provide excellent Palmer amaranth control; however, their application is limited before planting crops, which is often not possible due to unfavorable weather conditions. Agricultural biotechnology companies are developing new multiple HR crops that will allow the post-emergence application of respective herbicides for management of HR weeds, including Palmer amaranth. For the effective in-crop management of Palmer amaranth, and to reduce the potential for the evolution of other HR weeds, growers should apply herbicides with different modes of action in tank-mixture and should also incorporate cultural practices including inversion tillage and cover crops along with herbicide programs.
Author : Holden Douglas Bell
Publisher :
ISBN 13 : 9781321385618
Total Pages : 266 pages
Book Rating : 4.3/5 (856 download)
Download or read book Integration of Herbicide Programs with Cultural and Mechanical Practices for Managing Glyphosate-resistant Palmer Amaranth (amaranthus Palmeri) in Soybean (glycine Max) written by Holden Douglas Bell and published by . This book was released on 2014 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicide-resistant Palmer amaranth is the most troublesome weed in Arkansas row crops, causing producers to rely heavily on multiple mechanisms of action to reduce selection pressure for further evolution of herbicide resistance and to successfully produce a profitable crop. It is critical for the sustainability of weed management not only to adequately control this weed but also to reduce the soil seedbank using both non-chemical and chemical practices. Studies were conducted to determine the effect of soybean row spacing, seeding rate, and herbicide program on Palmer amaranth emergence, survival, and seed production in soybean, the effect of drill-seeded soybean population on Palmer amaranth emergence with and without a residual preemergence (PRE)-applied herbicide, and the impact of integrating cover crops and deep tillage with herbicide programs for glyphosate-resistant Palmer amaranth control in glyphosate- and glufosinate-resistant soybean. Herbicide application timing and choice of herbicide had more of an impact on Palmer amaranth control than either row spacing or seeding rate and greater control was observed in PRE plus postemergence (POST)-applied residual programs compared to POST-only residual programs, regardless of seeding rate and row spacing. Narrow-row soybean reached 95% canopy formation quicker than plants in wide rows, in turn resulting in greater suppression of Palmer amaranth emergence. In drill-seeded soybean, a PRE-applied residual herbicide was more beneficial in reducing Palmer amaranth emergence than increasing soybean density. Using a combination of cover crop and deep tillage along with the addition of a PRE followed by POST-applied residual herbicide program, Palmer amaranth was effectively controlled throughout the season with limited weed seed return to the soil seedbank in both glufosinate- and glyphosate-resistant soybean. Overall, herbicide programs were the strongest factor influencing Palmer amaranth control; however, the addition of a cover crop, deep tillage, and narrow row spacing play a vital role in reducing selection pressure on herbicides, thus reducing risks for new cases of herbicide resistance.
Author : George Macmillan Botha
Publisher :
ISBN 13 : 9781267771346
Total Pages : 236 pages
Book Rating : 4.7/5 (713 download)
Download or read book Alternative Herbicide Control Options for Glyphosate-resistant Palmer Amaranth (amaranthus Palmeri) written by George Macmillan Botha and published by . This book was released on 2012 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: The occurrence of glyphosate-resistant (GR) Palmer amaranth has prompted a shift in weed management strategies worldwide. Studies were conducted with the aim to (1) establish and compare the degree of tolerance of GR Palmer amaranth populations; (2) assess the efficacy of glufosinate, tembotrione, 2,4-D or dicamba, applied alone or tank-mixed, on Palmer amaranth with higher tolerance to glufosinate in the greenhouse and corn field, and (3) establish the mechanism involved in the tolerance of Palmer amaranth to glufosinate. Tembotrione, 2,4-D, dicamba, and glufosinate applied at 1x controlled 80 to 100%, 98 to 100%, 84 to 100%, and 94 to 100% Palmer amaranth, respectively. Differential response of Palmer amaranth populations to the test herbicides existed. The potential of selecting for resistance was highest in tembotrione, followed by dicamba. In the tank mixture test, all herbicides applied individually at 1x rate controlled Pra-C population 99 to 100% in the greenhouse and 91 to 100% in the field study. In corn, the control in Pra-C, Mis-C, and STF-C populations was 33 to 54% for tembotrione, 68 to 89% for 2,4-D, and 96 to 100% for glufosinate applied at their commercial rates. The study showed that half rates of 2,4-D and glufosinate can be applied, only in combination, without significantly compromising Palmer amaranth control. The majority of glufosinate + tembotrione and some glufosinate + dicamba mixtures were not compatible; glufosinate + 2,4-D mixtures were generally additive and in few cases, synergistic. The reduced efficacy from antagonism was overcome by mixing 1x rates of the herbicides. Pra-C (tolerant) had 2-folds higher tolerance than Lee-A (susceptible), with LD50 values of 344 and 141 g ha-1, respectively. The basal activity of the tolerant population was 20% higher than that of the susceptible. Tolerance to glufosinate is certainly due to higher baseline activity of GS in the tolerant plants, which would require more herbicide molecule to cause substantial inhibition.
Author : Alfred Rankins
Publisher :
ISBN 13 :
Total Pages : 4 pages
Book Rating : 4.:/5 (171 download)
Download or read book Glyphosate-resistant Palmer Amaranth written by Alfred Rankins and published by . This book was released on 2007 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Kelsey Marie Rogers
Publisher :
ISBN 13 : 9781369757156
Total Pages : 80 pages
Book Rating : 4.7/5 (571 download)
Download or read book Integrating a Cereal Rye Cover Crop and Soybean Row Width With Herbicides to Manage Palmer Amaranth in Michigan written by Kelsey Marie Rogers and published by . This book was released on 2017 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Griff Michael Griffith
Publisher :
ISBN 13 : 9781303044779
Total Pages : 318 pages
Book Rating : 4.0/5 (447 download)
Download or read book Glyphosate-resistant Palmer Amaranth (amaranthus Palmeri) in Arkansas written by Griff Michael Griffith and published by . This book was released on 2013 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 2000, there have been thirteen weed species confirmed resistant (R) to glyphosate in the United States, six of those resistant species are present in Arkansas. The goal of this research was to confirm and to determine the level of resistance in two R Palmer amaranth biotypes from Mississippi (MC-R) and Lincoln (LC-R) Counties, Arkansas, and one susceptible (S) biotype from Clarendon County, South Carolina, which had never been exposed to glyphosate. Shikimic acid concentration over time was significantly greater in the S biotype than both the MC-R and LC-R biotypes. The lethal dose required to kill 50% (LD50) of the population was 2,255 and 3,223 g ae ha -1 for the MC-R and LC-R biotypes, respectively, and it was hypothesized that the two Arkansas biotypes each had a different resistance mechanism. Results indicate metabolism of glyphosate to its major metabolite, aminomethylphosphonic acid (AMPA), was not responsible for resistance in any biotype. Reduced absorption in the LC-R and limited translocation from the treated leaf in the MC-R were at least partially responsible for the observed resistance to glyphosate. The LC-R biotype effectively colonized a field within two years of a single resistant female producing ̃20,000 seed. Cotton lint yield was reduced over 100 kg ha-1 by some densities of LC-R Palmer, depending on the soil and relative elevation in that region. Several resistant management options exist in cotton; however, results indicate that timely herbicide applications based off of Palmer amaranth size are required for effective season-long control and management of the soil seedbank.
Author : Nathaniel Russell Thompson
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (17 download)
Download or read book Palmer Amaranth (Amaranthus Palmeri) Control in Double-crop Dicamba/glyphosate Resistant Soybean (Glycine Max) and Dicamba and 2,4-D Efficacy on Palmer Amaranth and Common Waterhemp (Amaranthus Rudis) written by Nathaniel Russell Thompson and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Auxin herbicides have been widely used for broadleaf weed control since the mid-1940's. With new auxinic herbicide-resistant traits in corn, soybean, and cotton, use of these herbicides is likely to increase. Glyphosate-resistant Palmer amaranth (Amaranthus palmeri) and common waterhemp (Amaranthus rudis) are two primary problematic weed species that will be targeted with dicamba and 2,4-D in the new systems. No-till double-crop soybean after winter wheat harvest is a popular cropping system in central and eastern Kansas, however, management of glyphosate resistant Palmer amaranth has become a serious issue. Field experiments were established near Manhattan and Hutchinson, KS, in 2016 and 2017, to compare seventeen herbicide treatments for control of Palmer amaranth and large crabgrass (Digitaria sanguinalis) in dicamba/glyphosate resistant no-till double-crop soybean after winter wheat. Herbicide programs that included a residual preemergence (PRE) treatment followed by a postemergence (POST) treatment offered greater Palmer amaranth control 8 weeks after planting when compared to PRE-only, POST-only and burndown-only treatments. All treatments that contained glyphosate POST provided complete control of large crabgrass compared to less than 43% control with PRE-only treatments. Soybean grain yield was greater in programs that included PRE followed by POST treatments, compared to PRE-only and burndown-only treatments. A second set of field experiments were established in 2017 near Manhattan and Ottawa, KS to evaluate dicamba and 2,4-D POST efficacy on Palmer amaranth and common waterhemp. Five rates of dicamba (140, 280, 560, 1121, and 2242 g ae ha−1) and 2,4-D (140, 280, 560, 1121, and 2242 g ae ha−1) were used to evaluate control of the Amaranthus spp. Each experiment was conducted twice at each location. Dicamba provided better Palmer amaranth and common waterhemp control than 2,4-D across the rates evaluated. Control of Palmer amaranth was 94% and 99% with dicamba rates of 1121 and 2242 g ae ha−1, respectively, but 2,4-D never provided more than 80% control at any rate. The highest rates of both dicamba and 2,4-D provided greater than 91% common waterhemp control, but control was less than 78% with all other rates of both herbicides. Palmer amaranth and common waterhemp control did not exceed 73% with the highest labelled POST rates of either dicamba or 2,4-D. Auxinic herbicide-resistant traits in corn, soybean, and cotton offer new options for controlling glyphosate-resistant Palmer amaranth and common waterhemp, however proper stewardship is vital to maintain their effectiveness.
