Weed management practices in Argentina crops

AbstractData from surveys are used to help quantitatively diagnose the relative importance of chemical and nonchemical management practices, identify weed problems, and provide potential solutions. However, to our knowledge, such surveys have not been conducted in Argentina. In 2016, advisors and crop producers from cropping areas across Argentina were surveyed through email with the objectives to identify the main weed species problems and assess the use of chemical and nonchemical weed management practices in different crop production areas in Argentina. Fleabane, pigweed, johnsongrass, fingergrass, goosegrass, barnyardgrass, and ryegrass were considered the most important weeds. More than 53% of the producers used only chemical options; 86% used chemical fallow (i.e., keeping weed free with chemical application); 62% used full herbicide rates; 46% used proper herbicide timing; 41% used multiple modes of action; and 32% used rotation of herbicide modes of action. The main nonchemical practices used were crop rotation (45%); avoiding seed production during (31%) and after (25%) the crop cycle; narrow row spacing (19%); and cultivars with greater competitive ability (18%). Less than 15% of the people surveyed used increased crop densities or altered date of sowing. There is a high dependence on chemical control in the main crops grown in Argentina. Extension efforts are needed to emphasize the importance of integrated weed management.

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Herbicide Timing and Rate Effects on Weed Management in Three Herbicide-Resistant Canola Systems

Weed Technology ◽

10.1614/wt-03-188r1 ◽

2004 ◽

Vol 18 (4) ◽

pp. 1006-1012 ◽

Cited By ~ 7

Author(s):

K. Neil Harker ◽

George W. Clayton ◽

John T. O'Donovan ◽

Robert E. Blackshaw ◽

F. Craig Stevenson

Keyword(s):

Weed Control ◽

Weed Management ◽

Management Practices ◽

Integrated Weed Management ◽

Weed Biomass ◽

Herbicide Resistant ◽

Leaf Stage ◽

Rate Effects ◽

Herbicide Timing ◽

Weed Removal

Herbicide-resistant canola dominates the canola market in Canada. A multiyear field experiment was conducted at three locations to investigate the effect of time of weed removal (two-, four-, or six-leaf canola) and herbicide rate (50 or 100% recommended) in three herbicide-resistant canola systems. Weeds were controlled in glufosinate-resistant canola (GLU) with glufosinate, in glyphosate-resistant canola (GLY) with glyphosate, and in imidazolinone-resistant canola (IMI) with a 50:50 mixture of imazamox and imazethapyr. Canola yields were similar among the three canola cultivar–herbicide systems. Yields were not influenced by 50 vs. 100% herbicide rates. Timing of weed removal had the greatest effect on canola yield, with weed removal at the four-leaf stage giving the highest yields in most cases. Percent dockage was often greater for GLU and IMI than for GLY. In comparison with the other treatments, dockage levels doubled for GLU after application at 50% herbicide rates. The consistency of monocot weed control was usually greater for GLY than for GLU or IMI systems. However, weed biomass data revealed no differences in dicot weed control consistency between IMI and GLY systems. Greater dockage and weed biomass variability after weed removal at the six-leaf stage or after low herbicide rates suggests higher weed seed production, which could constrain the adoption of integrated weed management practices in subsequent years.

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Effects of crop rotation and field management methods on weed density and species composition in the southeastern part of Latvia

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2015vol2.275 ◽

2015 ◽

Vol 2 ◽

pp. 235

Author(s):

Jevgenija Ņečajeva ◽

Zane Mintāle ◽

Ieva Dudele ◽

Anda Isoda-Krasovska ◽

Jolanta Čūrišķe ◽

...

Keyword(s):

Species Composition ◽

Weed Control ◽

Crop Rotation ◽

Weed Management ◽

Management Practices ◽

Integrated Weed Management ◽

Weed Species ◽

Southeastern Part ◽

Weed Density ◽

Field Management

<p class="R-AbstractKeywords"><span lang="EN-GB">Integrated weed management (IWM) is a complex approach to weed control that is based on use of several different methods complementing each other, instead of relying on one single method, like chemical weed control. Weed control methods that can be used as parts of IWM strategy include mechanical weed control, application of herbicides, low tillage, changes in the rate and application time of fertilizers, use of undersown crops and crop rotation. Weed surveys were carried out in 2013 and 2014 in the southeastern part of Latvia. The aim of this study was to assess the effect of crop rotation and other field management practices on weed density and weed species composition using the data collected in the surveys. Survey was carried out in the arable fields of conventional farms within four different size categories. One of the significant factors that explained the variation of weed composition within a field was a proportion of cereals in crop rotation within a four year period. Further surveys are required to estimate the effects of climatic variables. Density-dependence can also be important for practical management decisions for particular weed species and should be investigated.</span></p>

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Herbicide Resistance: Where are we? How did we Get here? Where are we Going?

Weed Technology ◽

10.1017/s0890037x00024325 ◽

1995 ◽

Vol 9 (4) ◽

pp. 850-856 ◽

Cited By ~ 19

Author(s):

Dale L. Shaner

Keyword(s):

Weed Management ◽

Management Practices ◽

Resistance Management ◽

Cost Effective ◽

Integrated Weed Management ◽

Weed Species ◽

Environmentally Sustainable ◽

Development Of Resistance ◽

Working Groups ◽

Rigid Ryegrass

The first significant cases of herbicide-resistant weed populations were to the triazines in the 1970s. In the last 10 years there has been an increase in the number of weed populations that have become resistant to an array of herbicides. In some of these cases, like rigid ryegrass in Australia, a multitude of resistant biotypes has evolved with different mechanisms of resistance. If the present trend continues, the number of herbicides effective on certain weed species may diminish rapidly. To counteract this trend, industry has organized a number of intercompany working groups to specifically address the development of resistance and to implement plans to manage resistance. University and extension along with industry personnel across the world have begun educating growers on resistance management. However, this effort needs to be intensified to find new solutions for controlling weeds through the use of integrated weed management practices that incorporate new and established herbicides with cultural, mechanical, and biological control methods. The challenge is to develop cost effective, environmentally sustainable programs for weed control while maintaining the present efficiency in food and fiber production so that needs of an ever expanding human population can be met.

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Herbicide-Resistant Weeds: Management Tactics and Practices

Weed Technology ◽

10.1614/wt-05-084r1.1 ◽

2006 ◽

Vol 20 (3) ◽

pp. 793-814 ◽

Cited By ~ 205

Author(s):

Hugh J. Beckie

Keyword(s):

Herbicide Resistance ◽

Weed Management ◽

Management Practices ◽

Cropping Systems ◽

Integrated Weed Management ◽

Weed Species ◽

Herbicide Resistant ◽

Application Rates ◽

Selection For ◽

Reactive Management

In input-intensive cropping systems around the world, farmers rarely proactively manage weeds to prevent or delay the selection for herbicide resistance. Farmers usually increase the adoption of integrated weed management practices only after herbicide resistance has evolved, although herbicides continue to be the dominant method of weed control. Intergroup herbicide resistance in various weed species has been the main impetus for changes in management practices and adoption of cropping systems that reduce selection for resistance. The effectiveness and adoption of herbicide and nonherbicide tactics and practices for the proactive and reactive management of herbicide-resistant (HR) weeds are reviewed. Herbicide tactics include sequences and rotations, mixtures, application rates, site-specific application, and use of HR crops. Nonherbicide weed-management practices or nonselective herbicides applied preplant or in crop, integrated with less-frequent selective herbicide use in diversified cropping systems, have mitigated the evolution, spread, and economic impact of HR weeds.

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A Statewide Survey of Stakeholders to Assess the Problem Weeds and Weed Management Practices in Nebraska

Weed Technology ◽

10.1017/wet.2018.35 ◽

2018 ◽

Vol 32 (5) ◽

pp. 642-655 ◽

Cited By ~ 15

Author(s):

Debalin Sarangi ◽

Amit J. Jhala

Keyword(s):

Weed Management ◽

Crop Production ◽

Management Practices ◽

Acetolactate Synthase ◽

Grain Sorghum ◽

Primary Concern ◽

Weed Species ◽

Common Waterhemp ◽

Herbicide Resistant ◽

Crop Area

AbstractStakeholders were surveyed across Nebraska to identify the problem weeds and assess common weed management practices. A total of 425 responses were returned across four Nebraska extension districts (Northeast, Panhandle, Southeast, and West Central). Collectively, 61.2% of total farmed or scouted areas in Nebraska were under no-till production, and corn and soybean were the major crops (82.3% of total farmed or scouted area). Common waterhemp, horseweed, and kochia were the most problematic weeds statewide. Widespread occurrence of glyphosate-resistant (GR) weeds such as common waterhemp, horseweed, kochia, and Palmer amaranth were a serious problem in GR crop production. Additionally, 60% of growers in Nebraska reported the presence of at least one GR weed species on their farms. The most commonly used preplant burndown herbicides were 2,4-D and glyphosate, followed by saflufenacil and dicamba. In Nebraska, 74% and 59% of corn and soybean growers, respectively, were using PRE herbicides; however, more than 80% of growers were using POST herbicides for in-crop weed management. Atrazine alone or in premix or tank mix with mesotrione,S-metolachlor, or acetochlor were the most widely applied PRE herbicides in corn and grain sorghum, whereas the most commonly used PRE herbicides in soybean were the inhibitors of acetolactate synthase (ALS) and protoporphyrinogen oxidase (PPO). Glyphosate was the most frequent choice of the survey respondents as a POST herbicide in GR corn and soybean; 2,4-D was the most commonly used POST herbicide in grain sorghum and wheat. In Nebraska, only 5.2% of total crop area was planted with glufosinate-resistant crops. Most of the respondents (89%) were aware of the new multiple herbicide–resistant crops, and 80% of them listed physical drift and volatility of the auxinic herbicides as their primary concern. Forty-eight percent of survey respondents identified herbicide-resistant weed management as their primary research and extension priority.

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Recent Weed Control, Weed Management, and Integrated Weed Management

Weed Technology ◽

10.1614/wt-d-12-00109.1 ◽

2013 ◽

Vol 27 (1) ◽

pp. 1-11 ◽

Cited By ~ 109

Author(s):

K. Neil Harker ◽

John T. O'Donovan

Keyword(s):

Weed Control ◽

Weed Management ◽

Crop Production ◽

Management Practices ◽

Cropping Systems ◽

Arable Land ◽

The United States ◽

Integrated Weed Management ◽

Negative Consequences ◽

Research Activity

Integrated weed management (IWM) can be defined as a holistic approach to weed management that integrates different methods of weed control to provide the crop with an advantage over weeds. It is practiced globally at varying levels of adoption from farm to farm. IWM has the potential to restrict weed populations to manageable levels, reduce the environmental impact of individual weed management practices, increase cropping system sustainability, and reduce selection pressure for weed resistance to herbicides. There is some debate as to whether simple herbicidal weed control programs have now shifted to more diverse IWM cropping systems. Given the rapid evolution and spread of herbicide-resistant weeds and their negative consequences, one might predict that IWM research would currently be a prominent activity among weed scientists. Here we examine the level of research activity dedicated to weed control techniques and the assemblage of IWM techniques in cropping systems as evidenced by scientific paper publications from 1995 to June 1, 2012. Authors from the United States have published more weed and IWM-related articles than authors from any other country. When IWM articles were weighted as a proportion of country population, arable land, or crop production, authors from Switzerland, the Netherlands, New Zealand, Australia, and Canada were most prominent. Considerable evidence exists that research on nonherbicidal weed management strategies as well as strategies that integrate other weed management systems with herbicide use has increased. However, articles published on chemical control still eclipse any other weed management method. The latter emphasis continues to retard the development of weed science as a balanced discipline.

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Responses of Rice Flatsedge (Cyperus iria) and Barnyardgrass (Echinochloa crus-galli) to Rice Interference

Weed Science ◽

10.1614/ws-d-09-00050.1 ◽

2010 ◽

Vol 58 (3) ◽

pp. 204-208 ◽

Cited By ~ 25

Author(s):

Bhagirath S. Chauhan ◽

David E. Johnson

Keyword(s):

Weed Management ◽

Management Practices ◽

Stem Elongation ◽

Weight Ratio ◽

Stem Length ◽

Integrated Weed Management ◽

Shoot Biomass ◽

Weed Species ◽

Complete Control ◽

Crop Density

Rice flatsedge and barnyardgrass are widespread and competitive weeds in direct-seeded rice. Developing integrated weed management strategies that elevate suppression of weeds by rice through crop density, nutrition, and cultivar choice requires better understanding of the extent to which rice interferes with the growth of these weeds and how these species respond to resource limitation with crop interference. Rice interference reduced the height of barnyardgrass but did not affect height of rice flatsedge. These weed species were able to grow taller than rice and thus avoided being shaded. Increased specific stem length under crop interference may demonstrate a strategy of stem elongation to allow the top portion of the weeds to be kept out of shade. Rice interference reduced inflorescence and shoot biomass of both weed species. Barnyardgrass showed the ability to reduce the effects of rice interference by increasing leaf weight ratio. The present study shows that crop interference alone may reduce weed growth but may not give complete control of these weed species. This highlights the need for the integration of management practices to achieve control of these weed species.

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An Industry Perspective on Herbicide-Tolerant Crops

Weed Technology ◽

10.1017/s0890037x00035971 ◽

1992 ◽

Vol 6 (3) ◽

pp. 653-656 ◽

Cited By ~ 4

Author(s):

Robert T. Giaquinta

Keyword(s):

Weed Management ◽

Crop Production ◽

Management Practices ◽

Management Program ◽

Integrated Weed Management ◽

Societal Issues ◽

Herbicide Tolerant

Technology is now available to create herbicide-tolerant crops. This technology, when combined with environmentally and toxicologically sound herbicides and when used wisely in an integrated weed management program, can contribute positively to crop production. However, it is unlikely that herbicide-tolerant crops will revolutionize weed management. Instead, they will complement existing weed management practices and provide additional options to growers. Adoption and success of herbicide-tolerant crops will be dependent on several technical, environmental, business, economic, and societal issues. Industries that are developing herbicide-tolerant crops need to openly communicate and discuss both the value that their technology brings to agriculture and society and the strategies for ensuring its responsible use.

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Management of Pigweed (Amaranthusspp.) in Glufosinate-Resistant Soybean in the Midwest and Mid-South

Weed Technology ◽

10.1614/wt-d-15-00076.1 ◽

2016 ◽

Vol 30 (2) ◽

pp. 355-365 ◽

Cited By ~ 14

Author(s):

Thomas R. Butts ◽

Jason K. Norsworthy ◽

Greg R. Kruger ◽

Lowell D. Sandell ◽

Bryan G. Young ◽

...

Keyword(s):

Grain Yield ◽

Weed Management ◽

Production Systems ◽

Management Strategies ◽

Integrated Weed Management ◽

Weed Species ◽

Seeding Rate ◽

Row Width ◽

Narrow Row ◽

Sites Of Action

Pigweeds are among the most abundant and troublesome weed species across Midwest and mid-South soybean production systems because of their prolific growth characteristics and ability to rapidly evolve resistance to several herbicide sites of action. This has renewed interest in diversifying weed management strategies by implementing integrated weed management (IWM) programs to efficiently manage weeds, increase soybean light interception, and increase grain yield. Field studies were conducted across 16 site-years to determine the effectiveness of soybean row width, seeding rate, and herbicide strategy as components of IWM in glufosinate-resistant soybean. Sites were grouped according to optimum adaptation zones for soybean maturity groups (MGs). Across all MG regions, pigweed density and height at the POST herbicide timing, and end-of-season pigweed density, height, and fecundity were reduced in IWM programs using a PRE followed by (fb) POST herbicide strategy. Furthermore, a PRE fb POST herbicide strategy treatment increased soybean cumulative intercepted photosynthetically active radiation (CIPAR) and subsequently, soybean grain yield across all MG regions. Soybean row width and seeding rate manipulation effects were highly variable. Narrow row width (≤ 38 cm) and a high seeding rate (470,000 seeds ha−1) reduced end-of-season height and fecundity variably across MG regions compared with wide row width (≥ 76 cm) and moderate to low (322,000 to 173,000 seeds ha−1) seeding rates. However, narrow row widths and high seeding rates did not reduce pigweed density at the POST herbicide application timing or at soybean harvest. Across all MG regions, soybean CIPAR increased as soybean row width decreased and seeding rate increased; however, row width and seeding rate had variable effects on soybean yield. Furthermore, soybean CIPAR was not associated with end-of-season pigweed growth and fecundity. A PRE fb POST herbicide strategy was a necessary component for an IWM program as it simultaneously managed pigweeds, increased soybean CIPAR, and increased grain yield.

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Integrated weed management practices and sustainable food production among farmers in Kwara State, Nigeria

Open Agriculture ◽

10.1515/opag-2021-0221 ◽

2021 ◽

Vol 6 (1) ◽

pp. 124-134

Author(s):

Emmanuel Oyamedan Imoloame ◽

Ibrahim Folorunsho Ayanda ◽

Olayinka Jelili Yusuf

Keyword(s):

Weed Management ◽

Food Production ◽

Management Practices ◽

Sampling Technique ◽

Structured Interview ◽

Integrated Weed Management ◽

Sustainable Food ◽

Arable Crops ◽

Multi Stage ◽

Self Sufficiency

Abstract A survey was conducted in the Kwara State of Nigeria to study the integrated weed management (IWM) practices by farmers. This was in view of the poor weed management practices adopted by farmers, which is a major factor responsible for low yields of many arable crops in Kwara State. A multi-stage sampling technique was used to select a sample size of 480 respondents, and a structured interview schedule was used to elicit information from them. Data obtained were analyzed using descriptive statistics. Factor analysis was also carried out to examine the perception of farmers’ benefits of IWM. Results showed that the majority of farmers (29.4%) were youths, married (89.1%), and involved in medium-scale farming (47.2%). Furthermore, 50.8% of the farmers had primary or secondary education. Although farmers use different weed control methods, more than half of them (54.7%) use herbicides. Most farmers (92.6%) are engaged in the use of IWM, However, 73.5% of them use a combination of herbicides and hoe weeding. Although not properly practiced, farmers perceived IWM as having socio-environmental (29.229%) and techno-efficacious (23.495%) benefits over either hoe weeding or herbicides used alone. The findings suggest a need to train farmers on all aspects of IWM to achieve self-sufficiency in food production in Kwara State.

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