Sensitivity of lettuce cultivar Lucy Brown to pre-planting herbicide application

ABSTRACT Due to the low availability of herbicide active ingredients, the chemical weed management in lettuce crop is a challenge. The aim of this study was to evaluate the sensitivity of lettuce to the pre-planting application of the herbicides flumioxazin and trifluralin alone or in tank-mixture in lettuce, Lucy Brown cultivar. Two experiments were conducted. In experiment A, the soil was tilled before the herbicide application and it was tilled again before seedling transplanting. In experiment B, the soil was tilled just once before the herbicide application. The experimental design was in randomized blocks in a factorial scheme (3x3) +1 (2 factors with 3 levels and an additional control) with 4 replicates. We applied flumioxazin (120 g ha-1), trifluralin (450 g ha-1) and flumioxazin + trifluralin (120 + 450 g ha-1) in three different seasons before transplanting (0, 7 and 14 days). Lettuce productivity after trifluralin application (48.4 t ha-1) was higher than after flumioxazin application (16.8 t ha-1) in experiment A. In experiment B, flumioxazin decreased the number of lettuce leaves (25.6) at 14 DAT; no differences in lettuce productivity were verified, though. The herbicide trifluralin caused lower levels of phytotoxicity and was the most selective between the treatments when applied in the three seasons in both experiments.

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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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Weed management practices in glyphosate-tolerant and conventional cotton fields in Australia

Australian Journal of Experimental Agriculture ◽

10.1071/ea05163 ◽

2006 ◽

Vol 46 (9) ◽

pp. 1177 ◽

Cited By ~ 9

Author(s):

J. A. Werth ◽

C. Preston ◽

G. N. Roberts ◽

I. N. Taylor

Keyword(s):

Weed Control ◽

Weed Management ◽

Management Practices ◽

Herbicide Application ◽

Resistance Development ◽

Roundup Ready ◽

Use Patterns ◽

Management Techniques ◽

Cotton Fields ◽

Herbicide Use

Forty growers in 4 major cotton-growing regions in Australia were surveyed in 2003 to investigate how the adoption of glyphosate-tolerant cotton (Roundup Ready) had influenced herbicide use, weed management techniques, and whether changes to the weed spectrum could be identified. The 10 most common weeds reported on cotton fields were the same in glyphosate-tolerant and conventional fields in this survey. Herbicide use patterns were altered by the adoption of glyphosate-tolerant cotton with up to 6 times more glyphosate usage, but 21% fewer growers applying pre-emergence herbicides in glyphosate-tolerant fields. Other weed control practices such as the use of post-emergence herbicides, inter-row cultivation and hand hoeing were only reduced marginally. However, growers indicated that management practices are likely to change over time, especially with the introduction of enhanced glyphosate tolerance technology (Roundup Ready Flex), and anticipate a 32% decrease in the number of growers using alternative weed management practices. To date, management practices other than glyphosate use have not changed markedly in glyphosate-tolerant cotton indicating a conservative approach by growers adopting this technology and reflecting the narrow window of herbicide application. The range of weed control options still being employed in glyphosate-tolerant cotton would not increase the risk of glyphosate resistance development.

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Optimizing the Application Time of Pre-emergence Herbicide Pendimethalin and Oxyfluorfen Application for Effective Weed Management in Irrigated Blackgram (Vigna mungo L.) and Its Residue Persistence

Legume Research - An International Journal ◽

10.18805/lr-4478 ◽

2021 ◽

Author(s):

S. Selvakumar ◽

R. Ajaykumar ◽

A. Ammaiyappan

Keyword(s):

Field Experiment ◽

Weed Control ◽

Weed Management ◽

Block Design ◽

Vigna Mungo ◽

Application Time ◽

Herbicide Application ◽

Control Efficiency ◽

Randomized Block Design ◽

Weed Control Efficiency

Background: Time of pre-emergence herbicide application is an important factor that decides the efficiency of herbicide. If the pre-emergence herbicide is not applied at appropriate time, it may cause ineffective weed control or toxicity to crops. With this background, a field experiment was conducted at TNAU, Madurai to optimize the time of pre-emergence herbicides namely pendimethalin and oxyfluorfen application for effective weed management in irrigated blackgram. Methods: The experiment was laid out in randomized block design with three replication. Treatments were application of pendimethalin at 0.75 kg ha-1 and oxyfluorfen at 0.2 kg ha-1 on 1, 2, 3, 4 days after sowing, weed free check and unweeded check. Result: Results of the study revealed that oxyfluorfen gave maximum weed control efficiency as compared to pendimethalin, but toxicity to the crop was observed when oxyfluorfen was sprayed after 2 days of sowing. Yield and economics were achieved higher with application of 0.75 kg ha-1 of pendimethalin at 2 DAS, which was on par with application of 0.2 kg ha-1 of oxyfluorfen at 1 DAS due to lesser toxicity. Application of 0.75 kg ha-1 of pendimethalin and 0.2 kg ha-1 of oxyfluorfen didn’t leave any herbicide residue after harvest. Hence, application of 0.75 kg ha-1 of pendimethalin at 2 DAS and 0.2 kg ha-1 of oxyfluorfen at 1 DAS can be recommended for effective weed management in irrigated balckgram.

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Impact of site-specific weed management on herbicide savings and winter wheat yield

Plant Soil and Environment ◽

10.17221/599/2012-pse ◽

2013 ◽

Vol 59 (No. 3) ◽

pp. 101-107 ◽

Cited By ~ 12

Author(s):

P. Hamouz ◽

K. Hamouzová ◽

J. Holec ◽

L. Tyšer

Keyword(s):

Winter Wheat ◽

Weed Management ◽

Wheat Yield ◽

The Other ◽

Herbicide Application ◽

Site Specific ◽

Treatment Thresholds ◽

Patch Spraying ◽

Winter Wheat Yield ◽

Weed Infestation

An aggregated distribution pattern of weed populations provides opportunity to reduce the herbicide application if site-specific weed management is adopted. This work is focused on the practical testing of site-specific weed management in a winter wheat and the optimisation of the control thresholds. Patch spraying was applied to an experimental field in Central Bohemia. Total numbers of 512 application cells were arranged into 16 blocks, which allowed the randomisation of four treatments in four replications. Treatment 1 represented blanket spraying and the other treatments differed by the herbicide application thresholds. The weed infestation was estimated immediately before the post-emergence herbicide application. Treatment maps for every weed group were created based on the weed abundance data and relevant treatment thresholds. The herbicides were applied using a sprayer equipped with boom section control. The herbicide savings were calculated for every treatment and the differences in the grain yield between the treatments were tested using the analysis of variance. The site-specific applications provided herbicide savings ranging from 15.6% to 100% according to the herbicide and application threshold used. The differences in yield between the treatments were not statistically significant (P = 0.81). Thus, the yield was not lowered by site-specific weed management.

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Growth ofKochia scoparia, Salsola iberica, andTriticum aestivumvaries with temperature

Weed Science ◽

10.1017/s0043174500092043 ◽

1999 ◽

Vol 47 (4) ◽

pp. 435-439 ◽

Cited By ~ 3

Author(s):

Cathy A. Nord ◽

Calvin G. Messersmith ◽

John D. Nalewaja

Keyword(s):

Weed Management ◽

Growth Response ◽

Management Practices ◽

Fresh Weight ◽

Herbicide Application ◽

Kochia Scoparia ◽

Optimum Time ◽

Influence Of Temperature On ◽

Response To Temperature ◽

Salsola Iberica

Information on the influence of temperature on growth of springTriticum aestivumL. (wheat) relative toKochia scoparia(L.) Schrad. (kochia) andSalsola ibericaSennen and Pau (Russian thistle) could lead to more efficient weed management practices. An experiment was conducted to determine the growth of springT. aestivum, K. scoparia, andS. ibericaat 15, 23, and 30 C in growth chambers. Fresh weight at 15 C was greater for springT. aestivumthan forK. scopariaandS. iberica.Conversely, fresh weights at 23 or 30 C were greater forK. scopariaandS. ibericathan for springT. aestivum.Growth response to temperature is consistent with the physiological characteristics for photosynthesis of springT. aestivum, a C3plant, andK. scopariaandS. iberica, which are C4plants. The results indicate that cool temperatures that usually occur for early-seeded springT. aestivumwould give springT. aestivumthe competitive advantage overK. scopariaorS. iberica.Additionally, growing degree day (GDD) equations for height development ofK. scopariaandS. ibericawere determined and could be used to determine the optimum time for postemergence herbicide application.

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Weeds and yields of spring cereals as influenced by stubble-cultivation and reduced doses of herbicides in five long-term trials

The Journal of Agricultural Science ◽

10.1017/s0021859699007662 ◽

2000 ◽

Vol 134 (3) ◽

pp. 237-244 ◽

Cited By ~ 8

Author(s):

U. BOSTRÖM ◽

M. HANSSON ◽

H. FOGELFORS

Keyword(s):

Weed Management ◽

Plant Density ◽

Crop Yields ◽

Field Trials ◽

Herbicide Application ◽

Weed Species ◽

Full Dose ◽

Spring Cereals ◽

One Year

The influence of herbicides at reduced rates and repeated stubble-cultivation on weeds and crop yields was estimated in five field trials with spring-sown cereals situated in the south of Sweden during the autumn of 1989 until the spring of 1997. Stubble-cultivation was accomplished during 1989–1996, while herbicides were applied at 0, 1/8, 1/4 or 1/2 of full dose during 1990–1996.In the spring of 1997, i.e. after 7 years without herbicide application, seedling densities 3 weeks after weed emergence were 68–340/m2 at three sites and 535–610/m2 at two sites when averaged over tillage treatments.Averaged over herbicide doses, stubble-cultivation reduced the plant density of annual broad- leaved weeds by 6–32% at three sites and increased the density by 25% at one site. At the remaining site, the density was not significantly influenced. Stubble-cultivation reduced the populations of two perennial and seven annual weed species, while one species was stimulated and nine species showed null, or inconsistent, responses. In the spring of 1997, i.e. one year after the last herbicide application, the densities of weed seedlings in 1/8, 1/4 and 1/2-doses were 34, 46 and 56% lower, respectively, than in the untreated controls.Stubble-cultivation increased crop yields at four sites by 200 kg/ha as a mean over herbicide doses. At these four sites, averaged over 1993–1995, herbicides increased yields in plots that were not stubble-cultivated by 7, 8 and 10% in the 1/8, 1/4 and 1/2 of a full dose, respectively, relative to the untreated control. In 1996, herbicides increased yields at only two sites.It is concluded that a fruitful way for weed management with a low input of agrochemicals is to combine the use of herbicides at reduced rates with repeated stubble-cultivation.

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Quantifying Water Quality Improvements through Use of Precision Herbicide Application Technologies in a Dry-Tropical, Furrow-Irrigated Cropping System

Water ◽

10.3390/w11112326 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2326

Author(s):

Aaron M. Davis ◽

Catherine Neelamraju

Keyword(s):

Water Quality ◽

Weed Management ◽

Cropping System ◽

Farming System ◽

Freshwater Ecosystems ◽

Practice Change ◽

Quality Improvements ◽

Herbicide Application ◽

Relative Risks ◽

System Use

This study compared water quality effects of using precision herbicide application technologies and traditional spraying approaches across several regulated ‘priority’ and alternative pre- and post-emergent herbicides in a northern Australian cane farming system. Use of herbicide banding spray technologies resulted in pre-emergent herbicide load reductions, extending substantially beyond simple proportionate decreases in the amount of herbicide ingredient applied to paddocks. Aquatic risk assessment from resultant chemical mixtures leaving paddocks, and upscaled to local catchment concentrations, highlighted that precision application technologies could markedly reduce the ecological risk of pre-emergent herbicides. These risk reductions were, however, often complicated by the additional toxicity of post-emergent herbicides in mixtures, some associated with the adoption of band-spraying weed treatments. While the currently regulated priority herbicide, diuron, posed the greatest risk to the environment, alternative herbicides could still pose significant environmental risks, although these relative risks were lower at more ecologically relevant concentrations, typically found in the local freshwater ecosystems. Results underline the need for a carefully considered approach to integrating alternative herbicides and precision application technologies into improved weed management by irrigating cane farmers. Recent government changes to the appraisal of water quality improvement progress, from load-based to ecosystem-based targets, involving a much broader suite of herbicides, also appear likely to complicate assessment of the environmental impacts of practice change adoption for the industry.

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Effect of Temperature on Clopyralid Safety in Strawberry

Weed Technology ◽

10.1017/wet.2017.119 ◽

2018 ◽

Vol 32 (3) ◽

pp. 347-351 ◽

Cited By ~ 5

Author(s):

Shaun M. Sharpe ◽

Nathan S. Boyd ◽

Peter J. Dittmar ◽

Greg E. MacDonald ◽

Rebecca L. Darnell

Keyword(s):

Weed Management ◽

Growth Chamber ◽

Effect Of Temperature ◽

Herbicide Application ◽

Horticultural Crop ◽

Randomized Design ◽

Completely Randomized Design ◽

Pre Treatment ◽

Hand Weeding ◽

Growing Conditions

AbstractStrawberry is an important horticultural crop in Florida. The long growing season and escapes from fumigation and PRE herbicides necessitate POST weed management to maximize harvest potential and efficiency. Alternatives to hand-weeding are desirable, but clopyralid is the only broadleaf herbicide registered for use. Weed control may be improved by early-season clopyralid applications, but at risk of high temperature and increased strawberry injury. The effect of temperature on clopyralid safety on strawberry is unknown. We undertook a growth chamber experiment using a completely randomized design to determine crop safety under various temperature conditions across acclimation, herbicide application, and post-application periods. There was no effect of clopyralid on the number of strawberry leaves across all temperatures. Damage to the strawberry manifested as leaf malformations. Acclimation temperatures affected clopyralid-associated injury (p=0.0309), with increased leaf malformations at higher temperatures (27 C) compared to lower (18 C) temperatures. Pre-treatment temperatures did not affect clopyralid injury. Post-application temperature also affected clopyralid injury (p=0.0161), with increased leaf malformations at higher temperatures compared to lower ones. Clopyralid application did not reduce flowering or biomass production in the growth chamber. If leaf malformations are to be avoided, consideration to growing conditions prior to application is advisable, especially if applying clopyralid early in the season.

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Effect of tillage on timing ofSetariaspp. emergence and growth

Weed Science ◽

10.1017/s0043174500092274 ◽

1999 ◽

Vol 47 (5) ◽

pp. 563-570 ◽

Cited By ~ 6

Author(s):

Lizabeth A. B. Stahl ◽

Gregg A. Johnson ◽

Ronald L. Wyse ◽

Douglas D. Buhler ◽

Jeffrey L. Gunsolus

Keyword(s):

Seed Production ◽

Weed Management ◽

Cropping Systems ◽

Field Research ◽

Herbicide Application ◽

Tillage Systems ◽

Early Application ◽

Setaria Faberi ◽

Tillage System ◽

Soil Seedbank

Weed management can be a significant challenge in cropping systems, partly because the effects of tillage systems on weed seedbank and seedling population dynamics are not well understood. Field research was conducted from 1994 to 1996 in established tillage plots consisting of moldboard plow (MP), chisel plow (CP), and no-tillage (NT). The objectives were to determine the effects of long-term tillage systems on the timing and duration ofSetariaspp. emergence and percentage cumulative emergence from the soil seedbank and to investigate the effect of tillage onSetariaspp. density and seed production following glyphosate application atSetariaspp. heights of 5, 10, and 15 cm. NT contained a greater number ofSetariaspp. seed in the 0- to 1-, 1- to 3-, and 3- to 6-cm depths than MP or CP systems. There was little difference between the three tillage systems at depths greater than 6 cm.Setariaspp. emergence was greater in NT than in MP or CP in 1994 and 1996 and greater than in MP in 1995. There was a substantial increase inSetariaspp. emergence in NT between 3 and 4 weeks after planting (WAP) in 1994 and between 5 and 6 WAP in 1995 and 1996. Significant emergence did not occur past 5 to 6 WAP in 1994 and 1995 but continued over a longer period of time in 1996.Setariaspp. plants consistently reached targeted herbicide application heights 4 to 9 d earlier in NT than in CP and MP. In 1994, finalSetariaspp. density was greater in NT compared to CP and MP at the 5- and 10-cm herbicide application timings. When glyphosate was applied to 15-cm-tallSetaria, very few weeds were present following application across all tillage systems. In 1995, NT resulted in greaterSetariaspp. density than MP or CP across all application timings. There was no difference in finalSetariaspp. density between MP and CP across all glyphosate timings in 1994 and 1995. Seed production was negligible in MP and CP, regardless of glyphosate timing. In NT, however, significant seed production occurred, especially with early application. Results indicate that the effectiveness of nonresidual herbicides forSetaria faberiHerrm. control is influenced by tillage system and the timing of application.

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African star grass response to postemergence herbicides

Ciência e Agrotecnologia ◽

10.1590/1413-7054201943026918 ◽

2019 ◽

Vol 43 ◽

Cited By ~ 1

Author(s):

Alexandre Magno Brighenti ◽

Flávio Rodrigo Gandolfi Benites ◽

Fausto Souza Sobrinho

Keyword(s):

Nonionic Surfactant ◽

Weed Management ◽

Dry Matter ◽

Field Experiments ◽

Crop Management ◽

Mineral Oil ◽

Dry Matter Yield ◽

Herbicide Application ◽

Cynodon Nlemfuensis ◽

Postemergence Herbicides

ABSTRACT Cynodon nlemfuensis Vanderyst, commonly called African star grass, is excellent forage in pasture formation and herd feeding. However, little information is available regarding weed management in areas of star grasses. Two field experiments were carried out in 2017 and 2018 to evaluate the response of African star grass to postemergence herbicides. The treatments applied were as follows: 2,4-D (1,340.0 g ae ha-1); 2,4-D + picloram (720.0 +192.0 g ae ha-1 + 0.3% v/v nonionic surfactant); fluroxypyr + picloram (80.0 + 80.0 g ae ha-1 + 0.3% v/v mineral oil); fluroxypyr + aminopyralid (160.0 + 80.0 g ae ha-1 + 0.3% v/v mineral oil); fluroxypyr + triclopyr (320.0 + 960.0 g ae ha-1 + 0.3% v/v mineral oil); bentazon (720.0 g ai ha-1 + 0.5% v/v mineral oil); imazapyr (25.0 g ai ha-1); monosodium methyl arsenate (MSMA) (1,440.0 g ai ha-1 + 0.1% v/v nonionic surfactant); atrazine + S-metolachlor (1,480.0 + 1,160.0 g ai ha-1); atrazine + tembotrione (1,000.0 + 100.8 g ai ha-1 + 0.3% v/v mineral oil) and a control without herbicide application. The most phytotoxic treatments for the African star grass plants were fluroxypyr + amininopyralid, fluroxypyr + triclopyr and atrazine + tembotrione. The dry matter yield of star grass plants was not reduced by the applications of 2,4-D, 2,4-D + picloram, bentazon, imazapyr, MSMA and atrazine + S-metolachlor. These herbicides can be considered potential practices in African star grass crop management.

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