Integrated Systems of Weed Management in Organic Transplanted Vidalia® Sweet Onion Production

Field experiments were conducted from 2008 through 2010 near Lyons, GA, to develop integrated weed management systems for organic Vidalia® sweet onion (Allium cepa) production. Treatments were a factorial arrangement of summer solarization, cultivation with a tine weeder, and a clove oil herbicide. Plots were solarized with clear plastic mulch during the summer fallow period before transplanting onion. Cultivation treatments were twice at 2-week intervals, four times at 2-week intervals, and a noncultivated control. Herbicide treatments were clove oil plus vinegar, clove oil plus an emulsified petroleum oil (EPO) insecticide used as an adjuvant, and a nontreated control. ‘Savannah Sweet’ onions were transplanted in early-December each year, with cultivation and herbicide applications events occurring the following January and February. Onions were harvested the following spring. In addition to yield measurement, a subsample of harvested onion was stored in a controlled atmospheric (CA) storage facility to evaluate treatment effects on diseases of stored onion. Summer fallow solarization did not control the cool-season weeds present in these trials. Cultivating transplanted onion with a tine weeder effectively managed cutleaf eveningprimrose (Oenothera laciniata) and swinecress (Coronopus didymus) and improved onion yields in 2 of 3 years. There was little difference in overall performance between two cultivations and four cultivations with the tine weeder. The 1 year of marginal weed control with the tine weeder was due to persistently wet soils during winter months that inhibited optimum performance of the implement. Clove oil, combined with vinegar or an EPO insecticide, provided marginal weed control and had no effect on onion yield. Diseases of stored onion were unaffected by any of the treatment combinations, although overall incidence of diseases of stored onion was higher in 2010 compared with other years. This corresponds with the 1 year of marginal weed control with the tine weeder, suggesting that the presence of weeds may be a factor related to disease incidence during storage.

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Integrated Weed Management Using Planting Pattern, Cultivar, and Herbicide in Dry-Seeded Rice in Northwest India

Weed Science ◽

10.1614/ws-d-13-00115.1 ◽

2014 ◽

Vol 62 (2) ◽

pp. 350-359 ◽

Cited By ~ 11

Author(s):

Gulshan Mahajan ◽

Vikas Poonia ◽

Bhagirath S. Chauhan

Keyword(s):

Grain Yield ◽

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Weed Suppression ◽

Integrated Weed Management ◽

Rice Grain ◽

Planting Pattern ◽

Weed Biomass ◽

Northwest India

Field experiments were conducted in Punjab, India, in 2011 and 2012 to study the integrated effect of planting pattern [uniform rows (20-cm spacing) and paired rows (15-, 25-, and 15-cm spacing)], cultivars (PR-115 and IET-21214), and weed control treatments (nontreated control, pendimethalin 750 g ai ha−1, bispyribac-sodium 25 g ai ha−1, and pendimethalin 750 g ha−1 followed by bispyribac-sodium 25 g ha−1) on weed suppression and rice grain yield in dry-seeded rice. In the nontreated control, IET-21214 had higher grain yield than PR-115 in both planting patterns. However, such differences were not observed within the herbicide treatment. IET-21214 in paired rows, even in nontreated control, provided grain yield (4.7 t ha−1) similar to that in uniform rows coupled with the sole application of pendimethalin (4.3 t ha−1) and bispyribac-sodium (5.0 t ha−1). In uniform rows, sequential application of pendimethalin (PRE) and bispyribac-sodium (POST) provided the highest grain yield among all the weed control treatments and this treatment produced grain yield of 5.9 and 6.1 t ha−1 for PR-115 and IET-21214, respectively. Similarly, in paired rows, PR-115 in paired rows treated with sequential application of pendimethalin and bispyribac-sodium had highest grain yield (6.1 t ha−1) among all the weed control treatments. However, IET-21214 with the sole application of bispyribac-sodium produced grain yield similar to the sequential application of pendimethalin and bispyribac-sodium. At 30 days after sowing, PR-115 in paired rows coupled with pendimethalin application accrued weed biomass (10.7 g m−2) similar to the sequential application of pendimethalin and bispyribac-sodium coupled with uniform rows (8.1 g m−2). Similarly, IET-21214 with bispyribac-sodium application provided weed control similar to the sequential application of pendimethalin and bispyribac-sodium. Our study implied that grain yield of some cultivars could be improved by exploring their competitiveness through paired-row planting patterns with less use of herbicides.

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Tank Mix of Saflufenacil with Glyphosate and Pendimethalin for Broad-spectrum Weed Control in Florida Citrus

HortTechnology ◽

10.21273/horttech.21.5.606 ◽

2011 ◽

Vol 21 (5) ◽

pp. 606-615 ◽

Cited By ~ 6

Author(s):

Megh Singh ◽

Mayank Malik ◽

Analiza H.M. Ramirez ◽

Amit J. Jhala

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Management Program ◽

Integrated Weed Management ◽

Control Efficacy ◽

Citrus Production ◽

Herbicide Mixture ◽

Florida Citrus ◽

Citrus Trees

Citrus (Citrus spp.) is one of the most important crops in Florida agriculture. Weed control is a major component in citrus production practices. If not controlled, weeds may compete with citrus trees for nutrients, water, and light and may also increase pest problems. Herbicides are an important component of integrated weed management program in citrus. Saflufenacil, a new herbicide registered for broadleaf weed control in citrus, can be applied alone or in a tank mix with other herbicides to improve weed control efficacy. A total of six field experiments were conducted in 2008 and 2009 to evaluate the efficacy of saflufenacil applied alone or in a tank mix with glyphosate and pendimethalin for weed control. In addition, experiments were also conducted to evaluate phytotoxicity of saflufenacil applied at different rates and time intervals in citrus. The results suggested that saflufenacil applied alone was usually effective for early season broadleaf weed control; however, weed control efficacy reduced beyond 30 days after treatment (DAT) compared with a tank mix of saflufenacil, glyphosate, and pendimethalin. For example, control of weeds was ≤70% when saflufenacil or glyphosate applied alone compared with tank mix treatments at 60 and 90 DAT. Addition of pendimethalin as a tank mix partner usually resulted in better residual weed control compared with a tank mix of saflufenacil and glyphosate, and this herbicide mixture was comparable with grower's adopted standard treatment of a tank mix of glyphosate, norflurazon, and diuron and several other tank mix treatments. Saflufenacil applied once in a season at different rates or even in sequential applications did not injure citrus trees when applied according to label directions. It is concluded that with its novel mode of action, saflufenacil tank mixed with glyphosate and pendimethalin would provide citrus growers with another chemical tool to control broadleaf and grass weeds.

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Economics of integrated weed management in herbicide-resistant canola

Weed Science ◽

10.1614/ws-05-050r1.1 ◽

2006 ◽

Vol 54 (1) ◽

pp. 138-147 ◽

Cited By ~ 12

Author(s):

Bharat M. Upadhyay ◽

Elwin G. Smith ◽

G. W. Clayton ◽

K. N. Harker ◽

R. E. Blackshaw

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Production Systems ◽

Statistical Significance ◽

Integrated Weed Management ◽

Seeding Rate ◽

Herbicide Resistant ◽

Leaf Stage ◽

Weed Removal

Integrated weed management (IWM) decision strategies in herbicide-resistant canola-production systems were assessed for net returns and relative risk. Data from two field experiments conducted during 1998 to 2000 at two locations in Alberta, Canada, were evaluated. A herbicide-based experiment included combinations of herbicide system (glufosinate-, glyphosate-, and imazethapyr-resistant canola varieties), herbicide rate (50 and 100% of recommended dose), and time of weed removal (two-, four-, and six-leaf stages of canola). A seed-based experiment included canola variety (hybrid and open-pollinated), seeding rate (100, 150, and 200 seeds m−2), and time of weed removal (two-, four-, and six-leaf stages of canola). For the herbicide-based experiment, strategies with glyphosate were profitable at Lacombe, but both imazethapyr and glyphosate strategies were profitable at Lethbridge. Weed control at the four-leaf stage was at least as profitable as the two-leaf stage at both sites. For the seed-based experiment, the hybrid was more profitable than the open-pollinated cultivar, seed rates of 100 and 150 seeds m−2were more profitable than 200 seeds m−2, and weed control at the two- and four-leaf stages was more profitable than at the six-leaf stage. When risk of returns and statistical significance was considered, several strategies were included in the risk-efficient set for risk-averse and risk-neutral attitudes at each location. However, the glyphosate-resistant cultivar, the 50% herbicide rate, and weed control at four-leaf stage were more frequent in the risk-efficient IWM strategy set. The open-pollinated cultivar, 200 seeds m−2rate, and weed control at the six-leaf stage were less frequent in the set. The risk-efficient sets of IWM strategies were consistent across a range of canola prices.

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Integrated Management of Weeds in Direct-Seeded Rice in Cambodia

Agronomy ◽

10.3390/agronomy10101557 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1557

Author(s):

Robert Martin ◽

Bunna Som ◽

Joel Janiya ◽

Ratha Rien ◽

Sophea Yous ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Rice Field ◽

Field Experiments ◽

Integrated Management ◽

Weed Suppression ◽

Crop Damage ◽

Integrated Weed Management ◽

Crop Tolerance ◽

Direct Seeded

The objective of this work was to determine the value of improved establishment methods and herbicide applications as alternatives to high seeding rates to improve weed suppression in rice. Field experiments were carried out in 2010 and 2011 to determine optimal seeding rates and seeding methods with and without weed competition in wet-seeded rice. Under wet seeding conditions, drum seeding at 80 kg ha−1 was the most profitable treatment for both weed-free and unweeded rice. Although pre-emergence herbicides are beginning to be adopted in wet-seeded rice, they are seldom used in dry direct-seeded rice in Cambodia. Experiments were carried out in 2018 and 2019 to test crop tolerance and the efficacy of butachlor, oxadiazon, pendimethalin and pretilachlor applied post-sowing and pre-emergence to dry direct-seeded rice. Oxadiazon and butachlor, with the option for a post-emergence herbicide, provided effective weed control and a high grain yield in dry direct-seeded rice. Pretilachlor did not effectively control weeds under dry seeding conditions. Although pendimethalin exhibited good weed control, crop damage was a risk in poorly prepared seedbeds which typify Cambodian rice systems. With an effective integrated weed management strategy, it might be possible to safely reduce seeding rates below 80 kg ha−1 using drum or drill seeding machines.

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Bell Pepper and Weed Response to Dimethyl Disulfide plus Chloropicrin and Herbicide Systems

Weed Technology ◽

10.1017/wet.2017.74 ◽

2017 ◽

Vol 31 (5) ◽

pp. 694-700 ◽

Cited By ~ 6

Author(s):

Peter M. Eure ◽

A. Stanley Culpepper

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Dimethyl Disulfide ◽

Palmer Amaranth ◽

Bell Pepper ◽

Management Systems ◽

Plastic Mulch ◽

Yellow Nutsedge ◽

Phase Out

Bell pepper producers are faced with the challenge of controlling weeds following the phase-out of methyl bromide (MBr). Numerous attempts have been made to find a single fumigant or herbicide to control a broad spectrum of weeds. Adequate weed control in bell pepper will likely require weed management systems utilizing both fumigant and herbicide options. A weed management system including the fumigant dimethyl disulfide (DMDS) plus chloropicrin (Pic) plus the herbicide napropamide prior to transplant followed byS-metolachlor POST may be necessary to replace MBr. Field experiments were conducted during 2010 and 2011 near Ty Ty, Georgia to determine bell pepper and weed response to DMDS plus Pic or in systems with napropamide and/orS-metolachlor. Bell pepper were not significantly injured by DMDS plus Pic or napropamide. Injury caused byS-metolachlor was transient and plants fully recovered by 4 weeks after treatment (WAT). Yellow nutsedge control 6 WAT using DMDS plus Pic applied at 468 or 560 L ha−1controlled yellow nutsedge 91 to 95%. Large crabgrass control 6 WAT was 92 to 100% when DMDS plus Pic was applied at 468 or 560 L ha−1with or without a(n) herbicide (S-metolachlor or napropamide). Palmer Amaranth control prior to harvest was 21, 64, and 85% using DMDS plus Pic at 374, 468, or 560 L ha−1, respectively. DMDS plus Pic applied at 468 or 560 L ha-1with napropamide followed byS-metolachlor POST gave 95 to 99% control of Palmer amaranth 6 WAT. Consistent weed control and optimum yields were obtained when DMDS plus Pic was used at 468 L ha−1plus napropamide beneath plastic mulch followed byS-metolachlor POST.

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Effect of integrated weed management and nitrogen fertilization on the performance of rice under flood-prone lowland conditions

The Journal of Agricultural Science ◽

10.1017/s0021859697004887 ◽

1997 ◽

Vol 129 (4) ◽

pp. 409-418 ◽

Cited By ~ 9

Author(s):

A. R. SHARMA

Keyword(s):

Grain Yield ◽

Weed Control ◽

Water Depth ◽

Weed Management ◽

Field Experiments ◽

Conventional Tillage ◽

N Fertilizer ◽

Integrated Weed Management ◽

Growth Stages ◽

Crop Cultivation

Field experiments were conducted at Cuttack, India during 1991–94 to study the effect of tillage, methods of crop establishment and weed control at varying levels of N fertilizer on the performance of rice under flood-prone lowland conditions (0·60 cm water depth). The loss in grain yield of direct-sown rice caused by unchecked weed growth ranged from 18·2 to 59·2% in the different years, and was greater when N fertilizer was applied and when the conventional practice of ploughing the fields just before sowing was followed. Increasing the number of tillage operations before sowing improved the crop stand, reduced weed infestation and, thereby, increased the yield significantly compared with that achieved by conventional tillage. Summer ploughing rather than conventional tillage decreased weed dry weight at harvest by 15·8–53·2% and increased grain yield by 47·4–56·3%. A pre-emergence application of thiobencarb at 2·0 kg/ha, hand weeding once at 20 days of growth and post-establishment inter-crop cultivation at 37–42 days provided effective weed control and increased yield by 32·7–34·7, 36·7 and 28·7–83·9%, respectively. The efficiency of weed control and the resulting increase in rice yield were comparatively greater under puddling than with inter-crop cultivation and herbicide application. The loss in yield due to weeds was negligible when the crop was transplanted due to the incorporation of weeds during puddling and a greater water depth in the later growth stages. Therefore, the grain yield of rice was highest with transplanting followed closely by the direct-sown crop with post-establishment inter-crop cultivation. The response of direct-sown rice to N fertilization up to 60 kg N/ha decreased with fewer ploughings when no weed control measures were adopted. However, the grain yield increased significantly with N application up to 40 kg N/ha when weeds were controlled by cultural or chemical methods. The results suggested that an integrated weed management strategy involving summer ploughing, thiobencarb application and inter-crop cultivation is essential for effective weed control in direct-sown, flood-prone, lowland rice, in order to ensure higher N-use efficiency and crop productivity.

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Allyl Isothiocyanate as a Methyl Bromide Alternative for Weed Management in Polyethylene-Mulched Tomato

Weed Technology ◽

10.1614/wt-d-11-00152.1 ◽

2012 ◽

Vol 26 (3) ◽

pp. 449-454 ◽

Cited By ~ 8

Author(s):

Sanjeev K. Bangarwa ◽

Jason K. Norsworthy ◽

Edward E. Gbur

Keyword(s):

Weed Control ◽

Methyl Bromide ◽

Weed Management ◽

Field Experiments ◽

Allyl Isothiocyanate ◽

The United States ◽

Plastic Mulch ◽

Marketable Yield ◽

Tomato Production ◽

Tomato Yield

Methyl bromide has been widely used for weed control in polyethylene-mulched tomato production. With the phaseout of methyl bromide in the United States, an effective alternative is needed. Field experiments were conducted in 2007 and 2009 to determine if allyl isothiocyanate (ITC) would provide substantive weed control in tomato along with crop tolerance under low-density polyethylene (LDPE) and virtually impermeable film (VIF) mulch. Treatment factors included two mulch types (LDPE and VIF) and six rates of allyl ITC (0, 15, 75, 150, 750, 1,500 kg ha−1). A standard treatment of methyl bromide : chloropicrin (67 : 33%) at 390 kg ha−1under LDPE mulch was also established. Allyl ITC was broadcast applied and incorporated in soil before forming raised beds and laying plastic mulch. Tomatoes were transplanted 3 wk after applying allyl ITC or methyl bromide treatments. Tomato injury was ≤ 8% in all treatments at 2 wk after transplanting (WATP). Allyl ITC at 913 (± 191) kg ha−1was required to control yellow nutsedge, Palmer amaranth, and large crabgrass equivalent to methyl bromide at 6 WATP and maintain marketable tomato yield equivalent to methyl bromide treatment. VIF mulch was not effective in increasing weed control or improving the marketable yield of tomato over LDPE mulch. This research demonstrates that allyl ITC under an LDPE mulch can have a practical application for weed control in polyethylene-mulched tomato in the absence of methyl bromide.

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Assessment of weed and crop fitness in cover crop residues for integrated weed management

Weed Science ◽

10.1017/s0043174500091153 ◽

1998 ◽

Vol 46 (5) ◽

pp. 595-603 ◽

Cited By ~ 52

Author(s):

Martin M. Williams ◽

David A. Mortensen ◽

John W. Doran

Keyword(s):

Weed Control ◽

Weed Management ◽

Cover Crop ◽

Field Experiments ◽

Crop Residues ◽

Seedling Emergence ◽

Integrated Weed Management ◽

Weed Species ◽

Weed Growth ◽

Canopy Volume

Cover crop residues are not widely used for weed control because, as a stand-alone tactic, they do not effectively suppress all weeds and their duration of weed control is too short. Field experiments were conducted in 1995 and 1996, under both irrigated and rainfed conditions, to quantifyAmaranthusspp.,Setariaspp., and soybean emergence and growth in residues of fall-planted, spring-killed barley, rye, triticale, wheat, and hairy vetch. For both weed species, seedling emergence was reduced 3 wk after soybean planting by rye and wheat residues (≥ 2, 170 kg ha−1) in 1996. In 1996,Amaranthusspp. canopy volume was reduced 38 to 71% by residues 3 wk after planting. Likewise,Setariaspp. canopy biomass was reduced 37 to 97% in residues 5 wk after planting over both years. The response comparison index was used to identify frequency by which weed growth was placed at a disadvantage relative to soybean growth.Amaranthusspp. andSetariaspp. growth suppressions 3 to 5 wk after planting indicate potential times for intervention with other integrated weed management tactics such as reduced postemergence herbicide rates and interrow cultivation.

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Economic analysis of integrated weed management in field bean (Phaseolus vulgaris L.)

Plant Soil and Environment ◽

10.17221/4111-pse ◽

2011 ◽

Vol 49 (No. 4) ◽

pp. 183-189 ◽

Cited By ~ 1

Author(s):

E. Štefanić ◽

ŠtefanićI ◽

A.J. Murdoch

Keyword(s):

Weed Control ◽

Weed Management ◽

Management Practices ◽

Field Experiments ◽

Integrated Weed Management ◽

Field Bean ◽

Herbicide Application ◽

The North ◽

Late Emergence ◽

Residual Herbicide

Field experiments were conducted in field bean in the north-eastern part of theRepublicofCroatiato compare weed control and crop response under different management practices within the critical period of field bean production. The practices consisted in broadcast application of labelled rate of preemergence herbicide (pre) and postemergence herbicide application: (post) broadcast, band application over the rows, and band application combined with mechanical cultivation using of different herbicide doses recommended by the manufacturer (2×, 1×, 1/2×, 1/4×, 1/8×). In 1999, weed control with pre application of pendimethalin was superior to post bentazone application due to late emergence of weeds and lack of residual herbicide control. In 2000 bentazone combined with cycloxydim controlled weeds in field bean better than pre herbicide application. Based on the results of this research, single pre or post application of herbicide did not control a broad spectrum of weeds and did not provide the commercially acceptable full season control. Reduced rates of herbicide are not advisable under high weed pressure.

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Interaction of Preventive, Cultural, and Direct Methods for Integrated Weed Management in Winter Wheat

Agronomy ◽

10.3390/agronomy9090564 ◽

2019 ◽

Vol 9 (9) ◽

pp. 564 ◽

Cited By ~ 2

Author(s):

Alexander Menegat ◽

Anders T. S. Nilsson

Keyword(s):

Winter Wheat ◽

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Integrated Weed Management ◽

Wheat Seed ◽

Control Efficacy ◽

Seed Rate ◽

Alopecurus Myosuroides ◽

Seedbed Preparation

Crop rotations dominated by winter annual crops and relying on the use of herbicides to control weeds have resulted in weed communities dominated by a few highly specialized species such as Alopecurus myosuroides. Integrated weed management (IWM) represents a sensible strategy to target such difficult weeds, through a combination of preventive, cultural, and direct means. In six field trials over three years, we tested the effect of stale seedbed preparation, winter wheat seed rate, and chemical weed control strategy on Alopecurus myosuroides control efficacy and variability in efficacy. The field experiments were carried out under reduced tillage practice and without pre-sowing use of glyphosate. Stale seedbed preparation alone reduced A. myosuroides infestation level by 25% on average. No clear effect was found of increasing winter wheat seed rate from 300 to 400 seeds m−2. A combination of stale seedbed preparation and herbicide treatment in autumn and spring was found to be synergistic, improving weed control efficacy significantly and moreover reducing the variability in control efficacy and hence the risk for weed control failure.

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