Effect of Sprayer Output Volume and Adjuvants on Efficacy of Clove Oil for Weed Control in Organic Vidalia® Sweet Onion

Timely cultivation with a tine weeder and hand weeding are the primary tools for successful weed control in organic sweet onion (Allium cepa), but conditions frequently arise that delay the initial cultivation. Weeds that emerge during the delay are not effectively controlled by cultivation and herbicides derived from natural products may have a role to control the emerged weeds. It has been reported that clove oil herbicide was more effective when sprayers were calibrated for higher output (>50 gal/acre) compared with sprayers calibrated at ≈25 gal/acre. However, when clove oil was applied at the recommended rate of 10% by volume, herbicide cost was doubled when sprayer output volume was doubled. It was theorized that herbicide adjuvants might improve clove oil efficacy and reduce weed control cost by not needing to increase sprayer output volume. Trials were conducted from 2010 to 2012 to evaluate all possible combinations of two sprayer output volumes and five herbicide adjuvants used with clove oil (10% by volume) for cool season weed control. Sprayer output volumes evaluated were 25 and 50 gal/acre, using spray tips of differing orifice size. Adjuvants evaluated were a material composed of saponins, citric acid plus garlic extract, an emulsified petroleum oil (EPO) insecticide, a conventional petroleum oil adjuvant (POA), no adjuvant used with clove oil, and a nontreated control. Weed control was not consistently improved by applying clove oil (10% by volume) with a sprayer calibrated at 50 gal/acre compared with sprayer calibrated at 25 gal/acre. Improvements in weed control that were occasionally seen did not affect onion yield. Adjuvants provided minimal improvement in weed control from clove oil and did not consistently improve onion yield. Based on these results, clove oil does not provide suitable levels of weed control in organic Vidalia® sweet onion production to justify the expense.

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Efficacy Comparison of Some New Natural-Product Herbicides for Weed Control at Two Growth Stages

Weed Technology ◽

10.1614/wt-08-185.1 ◽

2009 ◽

Vol 23 (3) ◽

pp. 431-437 ◽

Cited By ~ 24

Author(s):

Hussein F. H. Abouziena ◽

Ahmad A. M. Omar ◽

Shiv D. Sharma ◽

Megh Singh

Keyword(s):

Acetic Acid ◽

Citric Acid ◽

Natural Product ◽

Weed Control ◽

Growth Stages ◽

Clove Oil ◽

Yellow Nutsedge ◽

Natural Herbicides ◽

Redroot Pigweed ◽

Wild Mustard

There is an urgent need to accelerate the development and implementation of effective organic-compliant herbicides that are environmentally safe and that help the producer meet increasing consumer demand for organic products. Therefore, greenhouse experiments were conducted to evaluate the effectiveness of acetic acid (5%), acetic acid (30%), citric acid (10%), citric acid (5%) + garlic (0.2%), citric acid (10%) + garlic (0.2%), clove oil (45.6%), and corn gluten meal (CGM) compounds as natural-product herbicides for weed control. The herbicides were applied to the broadleaf weeds stranglervine, wild mustard, black nightshade, sicklepod, velvetleaf, and redroot pigweed and to narrowleaf weeds crowfootgrass, Johnsongrass, annual ryegrass, goosegrass, green foxtail, and yellow nutsedge. The herbicides were applied POST at two weed growth stages, namely, two to four and four to six true-leaf stages. CGM was applied PPI in two soil types. Citric acid (5%) + garlic (0.2%) had the greatest control (98%) of younger broadleaf weeds, followed by acetic acid (30%) > CGM > citric acid (10%) > acetic acid (5%) > citric acid (10%) + garlic (0.2%), and clove oil. Wild mustard was most sensitive to these herbicides, whereas redroot pigweed was the least sensitive. Herbicides did not control narrowleaf weeds except for acetic acid (30%) when applied early POST (EPOST) and CGM. Acetic acid (30%) was phytotoxic to all broadleaf weeds and most narrowleaf weeds when applied EPOST. Delayed application until the four- to six-leaf stage significantly reduced efficacy; acetic acid was less sensitive to growth stage than other herbicides. These results will help to determine effective natural herbicides for controlling weeds in organic farming.

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Cool-Season Weed Control Using Ammonium Nonanoate and Cultivation in Organic Vidalia® Sweet Onion Production

Weed Technology ◽

10.1017/wet.2017.91 ◽

2017 ◽

Vol 32 (1) ◽

pp. 90-94

Author(s):

W. Carroll Johnson ◽

Xuelin Luo

Keyword(s):

Weed Control ◽

Cropping Systems ◽

Clove Oil ◽

Cool Season ◽

Control Cool ◽

Evening Primrose ◽

Statistical Interactions ◽

Degree Of Control ◽

Certified Organic ◽

Main Effects

AbstractAmmonium nonanoate is registered for weed control in certified organic cropping systems and may be useful to control cool-season weeds in organic Vidalia® sweet onion production. Ammonium nonanoate combined with tine-weeder cultivation was evaluated for weed control in organic onion in Georgia. There were no statistical interactions between main effects of herbicides and cultivation with a tine weeder for cool-season weed control and onion yield, indicating that ammonium nonanoate does not improve weed control compared with cultivation. Ammonium nonanoate at 4% and 6% did not adequately control weeds and onion yields were reduced. Ammonium nonanoate at 8% and 10% controlled cutleaf evening-primrose and lesser swinecress equal to the standard of d-limonene (14%), but the degree of control did not consistently protect onion yields from losses due to weeds. These results are in agreement with previous studies using clove oil and pelargonic acid. There is no advantage to using ammonium nonanoate for cool-season weed control in organic Vidalia® sweet onion production.

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Integrated weed management in transplanted rice: Options for addressing labor constraints and improving farmers’ income in Bangladesh

Weed Technology ◽

10.1017/wet.2021.50 ◽

2021 ◽

pp. 1-34

Author(s):

Sharif Ahmed ◽

Virender Kumar ◽

Murshedul Alam ◽

Mahbubur Rahman Dewan ◽

Khairul Alam Bhuiyan ◽

...

Keyword(s):

Grain Yield ◽

Weed Control ◽

Weed Management ◽

Cost Effective ◽

Integrated Weed Management ◽

Control Cost ◽

Control Practice ◽

Net Returns ◽

Transplanted Rice ◽

Hand Weeding

Abstract In Bangladesh, weeds in transplanted rice are largely controlled by labor-intensive and costly manual weeding, resulting in inadequate and untimely weed control. Labor scarcity coupled with intensive rice production has triggered increased use of herbicides. These factors warrant a cost-effective and strategic integrated weed management (IWM) approaches. On-farm trials with transplanted rice were conducted during monsoon (‘Aman’) season in 2016 and 2017 and winter (‘Boro’) season in 2016 to 2017 in agroecological zones 11 and 12 with ten treatments - seven herbicide-based IWM options, one mechanical weed control-based option, and two checks – farmers’ current weed control practice and weed-free, to assess effects on weed control, grain yield, labor use, and profitability. Compared to farmers’ practice, herbicide-based IWM options with mefenacet+bensulfuron-methyl as preemergence (PRE) followed by (fb) either bispyribac-sodium or penoxsulam as postemergence (POST) fb one hand-weeding (HW) were most profitable alternatives, with reductions in labor requirement by 11 to 25 persons-day ha−1 and total weed control cost by USD 44 to 94 ha−1, resulting in net returns increases by USD 54 to 77 ha−1 without compromising on grain yield. In contrast, IWM options with bispyrbac-sodium or penoxsulam as POST application fb one HW reduced yields by 12 to 13% and profits by USD 71 to 190 ha−1. Non-chemical option with mechanical weeding fb one HW performed similarly to farmers’ practice on yield and profitability. We suggest additional research to develop feasible herbicide-free approaches to weed management in transplanted rice that can offer competitive advantages to current practices.

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Pelargonic Acid for Weed Control in Organic Vidalia® Sweet Onion Production

HortTechnology ◽

10.21273/horttech.24.6.696 ◽

2014 ◽

Vol 24 (6) ◽

pp. 696-701 ◽

Cited By ~ 2

Author(s):

Wiley Carroll Johnson ◽

Jerry W. Davis

Keyword(s):

Weed Control ◽

Winter Season ◽

Field Trials ◽

Pelargonic Acid ◽

Yield Response ◽

Clove Oil ◽

Cool Season ◽

Control Efficacy ◽

Natural Sources ◽

Main Effects

Cultivation using a tine weeder is a proven means to manage weeds in organic Vidalia® sweet onion (Allium cepa) production. If the initial cultivation is delayed, emerged weeds are not controlled. In these cases, herbicides derived from natural products could be used to control the emerged weeds before the initial cultivation. Clove oil has been evaluated for this use, but cool-season weed control is inconsistent during the winter season when Vidalia® sweet onion are grown. Pelargonic acid is a herbicide that can be derived from natural sources or synthesized. Field trials were conducted from 2011 through 2013 to determine the efficacy of pelargonic acid for cool-season weed control in organic Vidalia® sweet onion. All possible combinations of four herbicides and three cultivation regimes using a tine weeder were evaluated. Herbicides evaluated were pelargonic acid (3% and 5% by vol.), clove oil [10% by vol. (2011 and 2012)], d-limonene [14% (2013 only)], and a nontreated control. Cultivation regimes were twice (2×) and four times (4×) at 2-week intervals, and a noncultivated control. Main effects of cultivation and herbicides were independent for all parameters, with no improvement when used in combination. Cultivation 2× and 4× controlled cool-season weeds and improved onion yields, which is consistent with previous research. Pelargonic acid (5%) controlled weeds similar to clove oil (2011 and 2012) and d-limonene (2013), with cool-season weed control efficacy being inconsistent among all herbicides. Onion yield response to weed control from any of the herbicides, including pelargonic acid, also was inconsistent. In organic onion production, inconsistent cool-season performance using pelargonic acid is similar to other herbicides derived from natural sources.

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

HortTechnology ◽

10.21273/horttech.22.1.64 ◽

2012 ◽

Vol 22 (1) ◽

pp. 64-69 ◽

Cited By ~ 3

Author(s):

W. Carroll Johnson ◽

David B. Langston ◽

Daniel D. MacLean ◽

F. Hunt Sanders ◽

Reid L. Torrance ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Disease Incidence ◽

Integrated Weed Management ◽

Clove Oil ◽

Plastic Mulch ◽

Cool Season ◽

Clear Plastic ◽

Summer Fallow

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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Effects of glyphosate-based herbicides and their active ingredients on earthworms, water infiltration and glyphosate leaching are influenced by soil properties

Environmental Sciences Europe ◽

10.1186/s12302-021-00492-0 ◽

2021 ◽

Vol 33 (1) ◽

Author(s):

Johann G. Zaller ◽

Maureen Weber ◽

Michael Maderthaner ◽

Edith Gruber ◽

Eszter Takács ◽

...

Keyword(s):

Organic Matter ◽

Soil Properties ◽

Weed Control ◽

Amaranthus Retroflexus ◽

Water Infiltration ◽

Soil Conditions ◽

Soil Functions ◽

Active Ingredients ◽

Hand Weeding ◽

Earthworm Activity

Abstract Background Glyphosate-based herbicides (GBHs) are among the most often used pesticides. The hundreds of GBHs used worldwide consist of the active ingredient (AI) glyphosate in form of different salts, possibly other AIs, and various mostly undisclosed co-formulants. Pesticide risk assessments are commonly performed using single AIs or GBHs at standard soil conditions without vegetation. In a greenhouse experiment, we established a weed population with common amaranth (Amaranthus retroflexus) to examine the effects of three GBHs (Roundup LB Plus, Roundup PowerFlex, Touchdown Quattro) and their corresponding AIs (salts of glyphosate isopropylammonium, potassium, diammonium) on the activity and physiological biomarkers (glutathione S-transferase, GST; acetylcholine esterase, AChE) of an ecologically relevant earthworm species (Lumbricus terrestris). GBHs and AIs were applied at recommended doses; hand weeding served as control. Experiments were established with two soil types differing in organic matter content (SOM; 3.0% vs. 4.1%) and other properties. Results Earthworm activity (casting and movement activity) decreased after application of glyphosate formulations or active ingredients compared to hand weeding. We found no consistent pattern that formulations had either higher or lower effects on earthworm activity than their active ingredients; rather, differences were substance-specific. Earthworm activity was little affected by soil organic matter levels. Biomarkers remained unaffected by weed control types; GST but not AChE was decreased under high SOM. Water infiltration after a simulated heavy rainfall was interactively affected by weed control types and SOM. Leachate amount was higher after application of formulations than active ingredients and was higher under low SOM. Glyphosate concentrations in soil and leachate were strongly affected by application of formulations or active ingredients and varied with SOM (significant weed control type x SOM interaction). Conclusions We found that both commercial formulations and pure active ingredients can influence earthworms with consequences on important soil functions. Glyphosate products showed increased, reduced or similar effects than pure glyphosate on particular soil functions; soil properties can substantially alter this. Especially at lower SOM, heavy rainfalls could lead to more glyphosate leaching into water bodies. A full disclosure of co-formulants would be necessary to further decipher their specific contributions to these inconsistent effects.

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Weed control in soybean (Glycine max L.) through resource management strategies and its influence on yield and nutrient uptake

Journal of Applied and Natural Science ◽

10.31018/jans.v9i1.1226 ◽

2017 ◽

Vol 9 (1) ◽

pp. 539-543

Author(s):

Aradhana Bali ◽

B. R. Bazaya ◽

Sandeep Rawal

Keyword(s):

Resource Management ◽

Nutrient Uptake ◽

Weed Control ◽

Weed Management ◽

Management Strategies ◽

Climatic Conditions ◽

Glycine Max L ◽

Effect On Yield ◽

Hand Weeding ◽

Quizalofop Ethyl

A field experiment was conducted during kharif season of 2011 at Research Farm, Sher-e-Kashmir University of Agricultural Sciences and Technology, Chatha, Jammu to evaluate the effect of weed management prac-tices on yield and nutrient uptake of soybean utilizing different resource management strategies. The lowest weed density and dry matter of weeds was recorded with hand weeding at 15 and 35 days after sowing (DAS) which was equally effective as imazethapyr @ 75 g ha -1 (PoE) fb hoeing at 35 DAS and quizalofop-ethyl @ 40 g ha-1 (PoE) fb hoeing at 35 DAS. All weed control treatments had significant effect on yield and nutrient up-take of soybean. Among the different weed control treatments, lowest N, P and K uptake by weeds were recorded in hand-weeding (15 and 35 DAS) which was statistically at par with imazethapyr @ 75 g ha -1 fb hoeing at 35 DAS. The maximum uptake by seed and straw were recorded in weed free which was statistically at par with twice hand weeding at 15 and 35 DAS, imazethapyr @ 75 g ha-1 fb hoeing at 35 DAS and quizalofop-ethyl @ 40 g ha-1 fb hoeing at 35 DAS. The highest seed and straw yield of soybean was harvested with hand-weeding (15 and 35 DAS) followed by imazethapyr @ 75 g ha -1 fb hoeing at 35 DAS. For the first time, soybean crop has been introduced in Jammu region for research purpose. Weed management varies with agro-climatic conditions. The study would be helpful to understand weed menace in this particular climatic condition of Jammu and to manage them combinedly and efficiently.

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Economics of Weed Control Methods in Transplanted Rice Fields in Mid-hill of Nepal

Journal of Agricultural Studies ◽

10.5296/jas.v8i1.15590 ◽

2020 ◽

Vol 8 (1) ◽

pp. 1

Author(s):

Robinson Adhikary ◽

Bishnu Bilas Adhikari ◽

Bishnu Prasad Kandel

Keyword(s):

Weed Control ◽

Computer Software ◽

R Package ◽

Cost Ratio ◽

Block Designs ◽

Control Methods ◽

Benefit Cost Ratio ◽

Transplanted Rice ◽

Hand Weeding ◽

Benefit Cost

To assess economic of different weed control methods on transplanted rice, a research was conducted at farmers’ fields, Bhanu-11, Rupakot, Nepal during the rainy season of 2017. The experiment was laid out using single factorial Randomized Complete Block Designs (RCBD) with three replications of ten treatments as one hand weeding at 21 Days After Transplanting (DAT) (T1); two hand weedings at 21 and 42 DAT (T2); three hand weedings at 21 42 & 63 DAT (T3); single conoweeding at 21 DAT (T4); double cono weedings at 21 &42 DAT (T5); triple cono weedings at 21, 42 &63 DAT (T6); butachlor as pre emergence (T7); butachlor with single manual weeding at 21 DAT (T8); butachlor with double manual weedings at 21 & 42 DAT (T9) and weedy check (T10). All collected data were subjected to analyzed by computer software R package. The results revealed that butachlor as pre-emergence (T7), showed that significantly higher gross return (Rs. 167.51thousand/ha), net profit (Rs. 96.11thousand/ha) and higher benefit-cost ratio (2.346), which is economically viable and profitable and can recommend to the farmers for rainfed lowland condition.

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Enhanced Activity of Single-Isomer Fenoxaprop on Cool-Season Grasses

Weed Technology ◽

10.1017/s0890037x00033935 ◽

1991 ◽

Vol 5 (4) ◽

pp. 826-833 ◽

Cited By ~ 6

Author(s):

George W. Mueller-Warrant

Keyword(s):

Weed Control ◽

Perennial Ryegrass ◽

Tall Fescue ◽

Fold Increase ◽

Cool Season ◽

Emulsifiable Concentrate ◽

Crop Tolerance ◽

Single Isomer ◽

Water Based ◽

Increased Activity

Formulations of fenoxaprop enriched in the R(+) isomer, HOE 46360-08H EW (described as an emulsifiable water-based formulation) and HOE 46360-05H EC (emulsifiable concentrate), were compared with the commercial racemate EC for control of roughstalk bluegrass and tolerance of perennial ryegrass and tall fescue grown for seed. The enriched EW and EC formulations were more than twice as active as the racemate per kg total fenoxaprop, despite enrichment to only 92 and 89% R(+) isomer purity, which should have increased activity by 1.84- and 1.78-fold, respectively. Increased activity was evident both as improved weed control and as decreased crop tolerance. Although the 3.69-fold increase in activity of HOE 46360 EW on roughstalk bluegrass relative to the racemate may be partly due to changes in the emulsion, the 3.06-fold increase in activity of HOE 46360 EC suggests that the S(-) isomer somehow interferes wih the activity of the R(+) isomer. Use of 280 g ai ha–1of the racemate could be replaced with 76 g ha–1of the EW or 92 g ha–1of the EC formulation of HOE 46360 for equivalent roughstalk bluegrass control, but with decreased crop tolerance in perennial ryegrass and tall fescue.

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Potential yield loss in grain sorghum (Sorghum bicolor) with weed interference in the United States

Weed Technology ◽

10.1017/wet.2020.12 ◽

2020 ◽

Vol 34 (4) ◽

pp. 624-629 ◽

Cited By ~ 1

Author(s):

J. Anita Dille ◽

Phillip W. Stahlman ◽

Curtis R. Thompson ◽

Brent W. Bean ◽

Nader Soltani ◽

...

Keyword(s):

United States ◽

Weed Control ◽

Weed Management ◽

Yield Loss ◽

Science Research ◽

The United States ◽

Grain Sorghum ◽

Control Cost ◽

Potential Yield ◽

Weed Interference

AbstractPotential yield losses in grain sorghum due to weed interference based on quantitative data from the major grain sorghum-growing areas of the United States are reported by the WSSA Weed Loss Committee. Weed scientists and extension specialists who researched weed control in grain sorghum provided data on grain sorghum yield loss due to weed interference in their region. Data were requested from up to 10 individual experiments per calendar year over 10 yr between 2007 and 2016. Based on the summarized information, farmers in Arkansas, Kansas, Missouri, Nebraska, South Dakota, and Texas would potentially lose an average of 37%, 38%, 30%, 56%, 61%, and 60% of their grain sorghum yield with no weed control, and have a corresponding annual monetary loss of US $19 million, 302 million, 7 million, 32 million, 25 million, and 314 million, respectively. The overall average yield loss due to weed interference was estimated to be 47% for this grain sorghum-growing region. Thus, US farmers would lose approximately 5,700 million kg of grain sorghum valued at approximately US $953 million annually if weeds are not controlled. With each dollar invested in weed management (based on estimated weed control cost of US $100 ha−1), there would be a return of US $3.80, highlighting the return on investment in weed management and the importance of continued weed science research for sustaining high grain sorghum yield and profitability in the United States.

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