Growth Stage of Alopecurus myosuroides Huds. Determines the Efficacy of Pinoxaden

Alopecurus myosuroides Huds. is an important pinoxaden-resistant grass weed in many countries of Europe. Recently, the low efficacy of pinoxaden was reported in winter cereals in Croatia, but a preliminary dose–response trial showed no herbicide resistance for the investigated weed population. Therefore, a two-year experiment was conducted under greenhouse conditions to determine the efficacy of various pinoxaden doses (20, 40 and 80 g a.i. ha−1) on weed visual injuries and biomass reduction after herbicide application at different growth stages. As expected, the maximum weed biomass reduction (97.3%) was achieved by applying the highest dose (80 g a.i. ha−1) at the earliest growth stage (ZCK 12–14). A pinoxaden dose of 20 g a.i. ha−1 resulted in satisfactory weed biomass reduction (88.9%) only when applied at ZCK 12–14. The recommended dose (40 g a.i. ha−1) also provided sufficient weed control up to the growth stage ZCK 21–25. Slightly delayed (ZCK 31–32) application of the recommended dose brought about a low weed biomass reduction (60.1%). Double than the recommended dose also failed to provide satisfactory weed control at the advanced weed growth stages (ZCK 31–32 and ZCK 37–39). Thus, reported low efficacy of pinoxaden is most likely because of delayed herbicide application when A. myosuroides is overgrown.

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Propelled abrasive grit applications for weed management in transitional corn grain production

Renewable Agriculture and Food Systems ◽

10.1017/s174217051700031x ◽

2017 ◽

Vol 34 (1) ◽

pp. 33-40 ◽

Cited By ~ 6

Author(s):

Mauricio Erazo-Barradas ◽

Claire N. Friedrichsen ◽

Frank Forcella ◽

Dan Humburg ◽

Sharon A. Clay

Keyword(s):

Weed Control ◽

Weed Management ◽

Developmental Stages ◽

Production Systems ◽

Growth Stages ◽

Corn Yield ◽

Weed Biomass ◽

Organic Systems ◽

Weed Growth ◽

Flame Weeding

AbstractWeed control is challenging to farmers who are transitioning from production systems that use synthetic herbicides to organic systems. A 2-year field study examined air-propelled corncob grit abrasion for in-row weed control efficacy and effect on corn yield. Grit was applied based on corn vegetative developmental stages with one (V1, V3 or V5), two (V1 + V3, V1 + V5, or V3 + V5), or three (V1 + V3 + V5) applications. Flame-weeding or cultivation was used after the V5 application for between-row weed control. Grit applications decreased in-row weed densities by about 60% (α = 0.05) and biomass up to 95% (α = 0.001). Between-row treatments provided similar control, and reduced weed biomass by 55% in 2013 (α = 0.01) and 86% (α = 0.001) in 2014. In-row grit treatments increased corn yield up to 44%, and yield was more influenced by in-row weeds than between row weeds. These results indicate that abrasive corncob grit for in-row weed control, supplemented with cultivation or flaming, can reduce weed biomass substantially and help maintain corn yield. However, timing and frequency of grit application need further refinement based on weed growth as influenced by climate, as treatments at similar corn growth stages did not consistently provide adequate weed control between years.

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Late-Season Weed Control in Glyphosate-Resistant Sugarbeet

Weed Technology ◽

10.1614/wt-d-10-00057.1 ◽

2011 ◽

Vol 25 (3) ◽

pp. 350-355 ◽

Cited By ~ 3

Author(s):

Robert G. Wilson ◽

Gustavo M. Sbatella

Keyword(s):

Weed Control ◽

Growth Stage ◽

Leaf Growth ◽

Field Trials ◽

Weed Suppression ◽

Growth Stages ◽

Weed Density ◽

Late Season ◽

True Leaf ◽

Weed Growth

Field trials were conducted from 2006 through 2008 to determine the influence of ethofumesate applied at planting followed by dimethenamid-p ors-metolachlor applied to emerged sugarbeet for late-season weed control in glyphosate-resistant sugarbeet. The entire plot area was kept weed-free until mid-June by applying glyphosate at the four- and eight-true-leaf sugarbeet growth stages. Glyphosate was not applied from mid-June until late-July to allow weed growth as a measure of the residual benefit from ethofumesate, dimethenamid-p, ands-metolachlor applied earlier in the growing season. Dimethenamid-p was not as effective ass-metolachlor in reducing weed density in mid-July. Late-season weed suppression from boths-metolachlor and dimethenamid-p benefitted from ethofumesate applied at planting. Dimethenamid-p applied when sugarbeet reached the six-true-leaf growth stage reduced weed density and sugarbeet injury more than earlier applications. The lowest weed density in mid-July was achieved whens-metolachlor was applied at the six- to eight-true-leaf sugarbeet growth stage compared to earlier growth stages. A planting time application of ethofumesate followed by two glyphosate applications pluss-metolachlor at the eight-true-leaf sugarbeet growth stage provided 89% more weed control in mid-July than glyphosate alone. Suppressing late-season weed development increased sugarbeet root yield 15% compared with areas not receiving ethofumesate ands-metolachlor.

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Growth and Phenology of Vulpia Myuros in Comparison with Apera Spica-Venti, Alopecurus Myosuroides and Lolium Multiflorum in Monoculture and in Winter Wheat

Plants ◽

10.3390/plants9111495 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1495

Author(s):

Muhammad Javaid Akhter ◽

Bo Melander ◽

Solvejg Kopp Mathiassen ◽

Rodrigo Labouriau ◽

Svend Vendelbo Nielsen ◽

...

Keyword(s):

Winter Wheat ◽

Weed Management ◽

Lolium Multiflorum ◽

Management Strategies ◽

Integrated Weed Management ◽

Growth Stages ◽

Neighborhood Design ◽

Alopecurus Myosuroides ◽

Winter Cereals ◽

Arable Weed

Vulpia myuros has become an increasing weed problem in winter cereals in Northern Europe. However, the information about V. myuros and its behavior as an arable weed is limited. Field and greenhouse experiments were conducted in 2017/18 and 2018/19, at the Department of Agroecology in Flakkebjerg, Denmark to investigate the emergence, phenological development and growth characteristics of V. myuros in monoculture and in mixture with winter wheat, in comparison to Apera spica-venti, Alopecurus myosuroides and Lolium multiflorum. V. myuros emerged earlier than A. myosuroides and A. spica-venti but later than L. multiflorum. Significant differences in phenological development were recorded among the species. Overall phenology of V. myuros was more similar to that of L. multiflorum than to A. myosuroides and A. spica-venti. V. myuros started seed shedding earlier than A. spica-venti and L. multiflorum but later than A. myosuroides. V. myuros was more sensitive to winter wheat competition in terms of biomass production and fecundity than the other species. Using a target-neighborhood design, responses of V. myuros and A. spica-venti to the increasing density of winter wheat were quantified. At early growth stages “BBCH 26–29”, V. myuros was suppressed less than A. spica-venti by winter wheat, while opposite responses were seen at later growth stages “BBCH 39–47” and “BBCH 81–90”. No significant differences in fecundity characteristics were observed between the two species in response to increasing winter wheat density. The information on the behavior of V. myuros gathered by the current study can support the development of effective integrated weed management strategies for V. myuros.

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Hormesis with glyphosate depends on coffee growth stage

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652013005000027 ◽

2013 ◽

Vol 85 (2) ◽

pp. 813-822 ◽

Cited By ~ 25

Author(s):

LEONARDO B. DE CARVALHO ◽

PEDRO L.C.A. ALVES ◽

STEPHEN O. DUKE

Keyword(s):

Plant Growth ◽

Weed Management ◽

Growth Stage ◽

Growth Stages ◽

Coffee Plant ◽

Herbicide Application ◽

Coffee Plantations ◽

Plant Growth Stages ◽

Coffee Plants ◽

Almost All

Weed management systems in almost all Brazilian coffee plantations allow herbicide spray to drift on crop plants. In order to evaluate if there is any effect of the most commonly used herbicide in coffee production, glyphosate, on coffee plants, a range of glyphosate doses were applied directly on coffee plants at two distinct plant growth stages. Although growth of both young and old plants was reduced at higher glyphosate doses, low doses caused no effects on growth characteristics of young plants and stimulated growth of older plants. Therefore, hormesis with glyphosate is dependent on coffee plant growth stage at the time of herbicide application.

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The critical weed-free period in glyphosate-resistant soybean in Ontario is similar to previous estimates using glyphosate-susceptible soybean

Canadian Journal of Plant Science ◽

10.1139/cjps-2018-0049 ◽

2019 ◽

Vol 99 (4) ◽

pp. 437-443

Author(s):

Nader Soltani ◽

Robert E. Nurse ◽

Amit J. Jhala ◽

Peter H. Sikkema

Keyword(s):

Growth Stage ◽

Field Experiments ◽

Yield Loss ◽

Growth Stages ◽

Weed Species ◽

Weed Biomass ◽

Weed Density ◽

Weed Interference ◽

Beginning Of Flowering ◽

Minimal Reduction

A study consisting of 13 field experiments was conducted during 2014–2016 in southwestern Ontario and southcentral Nebraska (Clay Center) to determine the effect of late-emerging weeds on the yield of glyphosate-resistant soybean. Soybean was maintained weed-free with glyphosate (900 g ae ha−1) up to the VC (cotyledon), V1 (first trifoliate), V2 (second trifoliate), V3 (third trifoliate), V4 (fourth trifoliate), and R1 (beginning of flowering) growth stages, after which weeds were allowed to naturally infest the soybean plots. The total weed density was reduced to 24%, 63%, 67%, 72%, 76%, and 92% in Environment 1 (Exeter, Harrow, and Ridgetown) when soybean was maintained weed-free up to the VC, V1, V2, V3, V4, and R1 soybean growth stages, respectively. The total weed biomass was reduced by 33%, 82%, 95%, 97%, 97%, and 100% in Environment 1 (Exeter, Harrow, and Ridgetown) and 28%, 100%, 100%, 100%, 100%, and 100% in Environment 2 (Clay Center) when soybean was maintained weed-free up to the VC, V1, V2, V3, V4, and R1 stages, respectively. The critical weed-free periods for a 2.5%, 5%, and 10% yield loss in soybean were the V1–V2, VC–V1, and VC–V1 soybean stages in Environment 1 (Exeter, Harrow, and Ridgetown) and V2–V3, V2–V3, and V1–V2 soybean stages in Environment 2 (Clay Center), respectively. For the weed species evaluated, there was a minimal reduction in weed biomass (5% or less) when soybean was maintained weed-free beyond the V3 soybean growth stage. These results shows that soybean must be maintained weed-free up to the V3 growth stage to minimize yield loss due to weed interference.

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Winter Wheat (Triticum aestivum) Growth Stage Effect on Paraquat Bioactivity

Weed Technology ◽

10.1017/s0890037x00028396 ◽

1991 ◽

Vol 5 (2) ◽

pp. 439-441

Author(s):

Randy L. Anderson ◽

David C. Nielsen

Keyword(s):

Triticum Aestivum ◽

Winter Wheat ◽

Growth Stage ◽

Time Of Day ◽

Growth Stages ◽

Leaf Stage ◽

Time Of Application ◽

Biomass Reduction

Paraquat was applied at 0.28 and 0.56 kg ai ha-1to winter wheat at five growth stages at 0800, 1300, and 1600 hr to determine whether growth stage or time of application influenced winter wheat response to paraquat. Paraquat bioactivity was affected by growth stage. Biomass reduction by paraquat was 84% when winter wheat was in the 1 to 3 leaf stage, but only 68% when application was delayed until tillering. Paraquat bioactivity continued to decrease at later growth stages. The time of day when paraquat was applied did not affect its bioactivity on winter wheat.

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Format of a Weed Control Database

Weed Technology ◽

10.1017/s0890037x00033571 ◽

1991 ◽

Vol 5 (1) ◽

pp. 221-228 ◽

Cited By ~ 1

Author(s):

George W. Mueller-Warrant

Keyword(s):

Weed Control ◽

Growth Stage ◽

Information Access ◽

Database Systems ◽

Original Data ◽

Relevant Information ◽

Growth Stages ◽

Complete Control ◽

Large Numbers ◽

Effect Level

Access to detailed descriptions of the effects of applying specific rates of herbicides to crops and weeds in various growth stages is hampered by the format in which the relevant information is stored. Compared to traditional formats of journal articles and herbicide registration labels, computer database systems could easily cross-reference data from large numbers of experiments and answer specific questions concerning herbicide performance under particular conditions. Availability of this type of information could have far-reaching consequences for herbicide users, consultants, researchers, and regulators. A preliminary format for storing weed control information in IBM-PC compatible computers was developed, including procedures to enter data and retrieve information. Weed control efficacy or crop injury data for all rates of a herbicide or tank-mixture applied at a specific growth stage in a single test are used to generate dose/response equations by means of regression analysis routines. The best fitting of these equations is then used to estimate herbicide rates that would provide ten categories of control, ranging from a “no observable effect level” (NOEL) up to complete control. Rates are estimated only for those categories either within or bordering the range of the observed data, the remaining categories are empty. The estimated rates are stored in the database, along with the original data and other qualifying information. Access to information is organized around searches for a single herbicide, plant species, or pair of species. Search output is presented in a tabular format listing species, growth stage, herbicide name, and herbicide rates for the ten categories: NOEL, 10, 30, 50, 70, 83, 90, 95, 98, and 100% control or injury.

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Weed Control Efficacy and Pinto Bean (Phaseolus vulgaris) Tolerance to Early Season Mechanical Weeding

Weed Technology ◽

10.1017/s0890037x00023800 ◽

1995 ◽

Vol 9 (3) ◽

pp. 531-534 ◽

Cited By ~ 8

Author(s):

Mark J. Vangessel ◽

Lori J. Wiles ◽

Edward E. Schweizer ◽

Phil Westra

Keyword(s):

Phaseolus Vulgaris ◽

Weed Control ◽

Weed Management ◽

Seed Weight ◽

Growth Stage ◽

Integrated Approach ◽

Growth Stages ◽

Weed Species ◽

Control Efficacy ◽

Pinto Bean

An integrated approach to weed management in pinto bean is needed since available herbicides seldom adequately control all weed species present in a field. A two-year study was conducted to assess weed control efficacy and pinto bean tolerance to mechanical weeding from a rotary hoe or flex-tine harrow at crook, unifoliolate, and trifoliolate stages of bean development. Weed control was similar for both implements and all timings in 1993. In 1994, mechanical weeding at trifoliolate and both crook and trifoliolate stages controlled more weeds than at other growth stages, regardless of type of implement. Using the flex-tine harrow reduced pinto bean stand, but results based on growth stage were not consistent each year. Damage to pinto bean hypocotyls and stems was observed with the flex-tine harrow used at both crook and trifoliolate stages in 1994. Rotary hoeing did not reduce pinto bean stand or cause injury. Yield and seed weight did not differ among treatments in either year.

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Weed management options in transgenic stacked and non transgenic maize (Zea mays) hybrids-A review

Agricultural Reviews ◽

10.18805/ag.r-1671 ◽

2017 ◽

Vol 38 (04) ◽

Cited By ~ 1

Author(s):

K. Sivagamy ◽

C. Chinnusamy ◽

P. Parasuraman

Keyword(s):

Weed Control ◽

Weed Management ◽

Crop Growth ◽

Control Programme ◽

Growth And Yield ◽

Growth Stages ◽

Management Options ◽

Maize Crop ◽

Weed Growth ◽

Vigorous Growth

Weeds are generally hardy species having fast growth, deep root system and capable of competing very efficiently with cultivated crops for the available resources and adversely affect the crop growth and yield. Weed management systems that rely on post emergence control assume that crops can tolerate competition for certain periods of time without suffering yield losses. Initial slow growth particularly at early crop growth stages and wider plant spacing of maize crop encourages fast and vigorous growth of weeds. It is of paramount importance that, competition from weeds must be minimized to achieve optimum yield. Among the different weed control methods, chemical method bears many advantages in suppressing weed growth and to get healthy and vigorous crop stand. Non-selective herbicide molecules with a variety of mode of action were discovered, developed and marketed for successful weed control programme.

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An Evaluation of Two Novel Cultivation Tools

Weed Technology ◽

10.1614/wt-d-11-00024.1 ◽

2012 ◽

Vol 26 (2) ◽

pp. 316-325 ◽

Cited By ~ 4

Author(s):

Glenn J. Evans ◽

Robin R. Bellinder ◽

Russell R. Hahn

Keyword(s):

Weed Control ◽

Weed Management ◽

Environmental Data ◽

Yield Response ◽

Growth Stages ◽

Operational Parameters ◽

Crop Response ◽

Weed Growth ◽

Operational Variables ◽

Organic Weed Management

Cultivation is a critical component of organic weed management and has relevance in conventional farming. Limitations with current cultivation tools include high costs, limited efficacy, and marginal applicability across a range of crops, soil types, soil moisture conditions, and weed growth stages. The objectives of this research were to compare the weed control potential of two novel tools, a block cultivator and a stirrup cultivator, with that of a conventional S-tine cultivator, and to evaluate crop response when each tool was used in pepper and broccoli. Block and stirrup cultivators were mounted on a toolbar with an S-tine sweep. In 2008, the tripart cultivator was tested in 20 independently replicated noncrop field events. Weed survival and reemergence data were collected from the cultivated area of each of the three tools. Environmental data were also collected. A multivariable model was created to assess the importance of cultivator design and environmental and operational variables on postcultivation weed survival. Additional trials in 2009 evaluated the yield response of pepper and broccoli to interrow cultivations with each tool. Cultivator design significantly influenced postcultivation weed survival (P < 0.0001). When weed survival was viewed collectively across all 20 cultivations, both novel cultivators significantly increased control. Relative to the S-tine sweep, the stirrup cultivator reduced weed survival by about one-third and the block cultivator reduced weed survival by greater than two-thirds. Of the 11 individually assessed environmental and operational parameters, 7 had significant implications for weed control with the sweep; 5 impacted control with the stirrup cultivator, and only 1 (surface weed cover at the time of cultivation) influenced control with the block cultivator. Crop response to each cultivator was identical. The block cultivator, because of its increased effectiveness and operational flexibility, has the potential to improve interrow mechanical weed management.

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