Effects of Preplant and Postplant Rotary Hoe Use on Weed Control, Soybean Pod Position, and Soybean Yield

Demand for organic food products has consistently increased for more than 20 yr. The largest obstacle to organic soybean production in the southeastern United States is weed management. Current organic soybean production relies on mechanical weed control, including multiple postplant rotary hoe uses. Although postplant rotary hoe use is effective at the weed germination stage, its efficacy is severely compromised by delays due to weather. Preplant rotary hoeing is also a practice that has been utilized for weed control but the effectiveness of this practice to reduce the need for multiple postplant rotary hoeing for organic soybean production in the southeastern United States has not been investigated. Preplant rotary hoe treatments included a weekly rotary hoeing 4 wk before planting, 2 wk before planting, and none. Postplant rotary hoe treatments consisted of zero, one, two, three, and four postplant rotary hoe uses. Weed control was increased with preplant rotary hoeing at Plymouth in 2006 and 2007 but this effect disappeared with the first postplant rotary hoeing. Multiple postplant rotary hoe uses decreased soybean plant populations, decreased soybean canopy height, lowered soybean pod position, and decreased soybean yield. Plant mapping revealed that the percentage of total nodes and pods below 30 cm was increased by increased frequency of postplant rotary hoe use.

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Herbicide-Based Weed Management for Soybean Production in the Far Eastern Region of Russia

Agronomy ◽

10.3390/agronomy10111823 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1823

Author(s):

Jong-Seok Song ◽

Ji-Hoon Chung ◽

Kyu Jong Lee ◽

Jihyung Kwon ◽

Jin-Won Kim ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Management System ◽

Field Experiments ◽

Yield Loss ◽

Eastern Region ◽

Primorsky Krai ◽

Control Efficacy ◽

Soybean Yield ◽

Soybean Production

This study was conducted to establish a weed management system based on the sequential application of pre-emergence (PRE) and post-emergence (POST) herbicides for soybean production in Primorsky krai. Field experiments were conducted for two years in a field located in Bogatyrka, Primorsky krai, Russia (N43°49′, E131°36′). No herbicide application resulted in significant soybean yield loss, 0.03–0.3 t ha−1, which is more than 91.6% yield loss compared with that of the weed-free plot. The PRE application of acetochlor showed good weed control efficacy (greater than 90% weed control) with acceptable soybean safety (less than 10% soybean damage), while the other PRE herbicides performed poorly in terms of weed control. The POST application of bentazon + acifluorfen, bentazon, and imazamox at 30 days after soybean sowing (DAS) showed good weed control efficacy with good soybean safety. Neither the PRE nor POST application alone showed a sufficient soybean yield protection, resulting in much lower soybean yield than the weed-free plot. The sequential application of acetochlor (PRE), followed by either bentazon + acifluorfen (POST) at 30 DAS in 2012 or bentazon + imazamox (POST) at 60 DAS in 2013 showed the best performance in soybean yields, 1.7 t and 1.9 t ha−1, respectively, provided with 724.5 US$ and 1155.6 US$ ha−1 of economic returns. For alternative PRE herbicides of acetochlor, which is now banned, our tests of the sequential application of S-metolachlor with other POST herbicides and the sole application of other PRE herbicides revealed that S-metolachlor and clomazone could also be considered. Our results thus demonstrate that the sequential applications of PRE and POST herbicides should be incorporated into the weed management system for soybean production in Primorsky krai, Russia.

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Model Simulasi dan Visualisasi Prediksi Potensi Hasil dan Produksi Kedelai di Jawa Timur

Jurnal Penelitian Pertanian Tanaman Pangan ◽

10.21082/jpptp.v34n3.2015.p195-201 ◽

2016 ◽

Vol 34 (3) ◽

pp. 195

Author(s):

Bambang S. Koentjoro ◽

Imas S. Sitanggang ◽

Abdul Karim Makarim

Keyword(s):

Simulation Model ◽

Systems Approach ◽

Yield Potential ◽

Soybean Plant ◽

Climatic Data ◽

Observation Data ◽

Potential Yield ◽

Soybean Yield ◽

Soybean Production ◽

Growth Simulator

<p>The prediction of national soybean yield and production could be improved its accuracy by integrating a simulation model and Geographic Information Systems (GIS). The objective of this research was to integrate a simulation model with a GIS, to predict the potential yield and production of soybean in the soybean production centers of East Java. This study was conducted from December 2013 till May 2014. The approach used in this study was a systems approach using a simulation model as solution to the problem. The model is SUCROS.SIM (Simple Universal Crops Growth Simulator), which was written using Powersim software and Spreadsheet in order to be fully integrated with GIS. The initial phase of the integration process between SUCROS.SIM and GIS are as follows (a) model validation, using input data of soybean plant assimilate partitioning, (b) climatic data (solar radiation, maximum and minimum temperatures) collected from the climatological station (BMKG) Karangploso Malang and (c) observation data of soybean yields of two varieties (Wilis and Argomulyo) at Muneng Experiment Station. It was found that the coefficients of determination of simulation model of soybean yield potential (R2) range from 0.945-0.992 and RMSE (Root Mean Square Error) values range from 0.11 to 0.25 t/ha. The average of soybean yield potential and production in 2012 at soybean production centers of East Java were 1.94 t/ha and 293,459 ton, respectively. The conclusion is SUCROS.SIM valid to be integrated with GIS.</p>

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Geographic Information System for Pigweed Distribution in the US Southeast

Weed Technology ◽

10.1017/wet.2017.118 ◽

2018 ◽

Vol 32 (1) ◽

pp. 20-26 ◽

Cited By ~ 1

Author(s):

Reginald S. Fletcher ◽

Krishna N. Reddy

Keyword(s):

United States ◽

Open Source ◽

Open Source Software ◽

Precision Agriculture ◽

Weed Management ◽

Southeastern United States ◽

Management Strategies ◽

Geographic Information ◽

County Level ◽

Support Tool

AbstractIn the southeastern United States, Amaranthus, or pigweed species, have become troublesome weeds in agricultural systems. To implement management strategies for the control of these species, agriculturalists need information on areas affected by pigweeds. Geographic information systems (GIS) afford users the ability to evaluate agricultural issues at local, county, state, national, and global levels. Also, they allow users to combine different layers of geographic information to help them develop strategic plans to solve problems. Furthermore, there is a growing interest in testing free and open-source GIS software for weed surveys. In this study, the free and open-source software QGIS was used to develop a geographic information database showing the distribution of pigweeds at the county level in the southeastern United States. The maps focused on the following pigweeds: Palmer amaranth, redroot pigweed, and tall waterhemp. Cultivated areas and glyphosate-resistant (GR) pigweed data were added to the GIS database. Database queries were used to demonstrate applications of the GIS for precision agriculture applications at the county level, such as tallying the number of counties affected by the pigweeds, identifying counties reporting GR pigweed, and identifying cultivated areas located in counties with GR pigweeds. This research demonstrated that free and open-source software such as QGIS has strong potential as a decision support tool, with implications for precision weed management at the county scale.

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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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Interaction of Prodiamine and Flumioxazin for Nursery Weed Control

Weed Technology ◽

10.1614/wt-d-10-00020.1 ◽

2010 ◽

Vol 24 (4) ◽

pp. 504-509 ◽

Cited By ~ 5

Author(s):

Glenn Wehtje ◽

Charles H. Gilliam ◽

Stephen C. Marble

Keyword(s):

United States ◽

Weed Control ◽

Southeastern United States ◽

Cost Effective ◽

Fresh Weight ◽

Weed Species ◽

Rate Range ◽

Nursery Production ◽

Control Research ◽

Large Crabgrass

Both prodiamine and flumioxazin are used in the nursery production and landscape maintenance industries in the southeastern United States for preemergence weed control. Research was conducted to determine whether a tank mixture of these two herbicides would be more effective than either component applied alone. Prodiamine alone, flumioxazin alone, and a 72 : 28 (by weight) prodiamine–flumioxazin mixture were each applied at a series of rates to containers filled with a pine bark–sand substrate that is typical for nursery production in the southeastern United States. Our intent was to have a rate range that hopefully extended from ineffective to lethal for each treatment series. Subsequent to treatment, containers were overseeded with either large crabgrass, spotted spurge, or eclipta. Percent control was determined by comparing treated weed foliage fresh weight to that of the appropriate nontreated control at 6 and 12 wk after application. ANOVA followed by nonlinear regression was used to evaluate the interaction of prodiamine and flumioxazin when combined and to determine the rate of each treatment series required for 95% control (if applicable) for each of the three weed species. Results varied with weed species. The mixture was synergistic and more cost effective than either of the components applied alone in controlling spotted spurge. With respect to large crabgrass control, the mixture was additive and slightly more cost effective than the components. Eclipta could only be controlled with flumioxazin, and this control was antagonized by the addition of prodiamine.

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Weed control and crop tolerance of micro-encapsulated acetochlor applied sequentially in glyphosate-resistant soybean

Canadian Journal of Plant Science ◽

10.4141/cjps-2014-422 ◽

2015 ◽

Vol 95 (5) ◽

pp. 973-981 ◽

Cited By ~ 6

Author(s):

Amit J. Jhala ◽

Mayank S. Malik ◽

John B. Willis

Keyword(s):

United States ◽

Weed Control ◽

Field Experiments ◽

The United States ◽

Soybean Yield ◽

Application Timing ◽

Common Waterhemp ◽

Weed Density ◽

Crop Tolerance ◽

Green Foxtail

Jhala, A. J., Malik, M. S. and Willis, J. B. 2015. Weed control and crop tolerance of micro-encapsulated acetochlor applied sequentially in glyphosate-resistant soybean. Can. J. Plant Sci. 95: 973–981. Acetochlor, an acetamide herbicide, has been used for many years for weed control in several crops, including soybean. Micro-encapsulated acetochlor has been recently registered for preplant (PP), pre-emergence (PRE), and post-emergence (POST) application in soybean in the United States. Information is not available regarding the sequential application of acetochlor for weed control and soybean tolerance. The objectives of this research were to determine the effect of application timing of micro-encapsulated acetochlor applied in tank-mixture with glyphosate in single or sequential applications for weed control in glyphosate-resistant soybean, and to determine its impact on soybean injury and yields. Field experiments were conducted at Clay Center, Nebraska, in 2012 and 2013, and at Waverly, Nebraska, in 2013. Acetochlor tank-mixed with glyphosate applied alone PP, PRE, or tank-mixed with flumioxazin, fomesafen, or sulfentrazone plus chlorimuron provided 99% control of common waterhemp, green foxtail, and velvetleaf at 15 d after planting (DAP); however, control declined to ≤40% at 100 DAP. Acetochlor tank-mixed with glyphosate applied PRE followed by early POST (V2 to V3 stage of soybean) or late POST (V4 to V5 stage) resulted in ≥90% control of common waterhemp and green foxtail, reduced weed density to ≤2 plants m−2 and biomass to ≤12 g m−2, and resulted in soybean yields >3775 kg ha−1. The sequential applications of glyphosate plus acetochlor applied PP followed by early POST or late POST resulted in equivalent weed control to the best herbicide combinations included in this study and soybean yield equivalent to the weed free control. Injury to soybean was <10% in each of the treatments evaluated. Micro-encapsulated acetochlor can be a good option for soybean growers for controlling grasses and small-seeded broadleaf weeds if applied in a PRE followed by POST herbicide program in tank-mixture with herbicides of other modes of action.

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A Survey of Weed Management in Organic Small Grains and Forage Systems in the Northwest United States

Weed Science ◽

10.1614/ws-d-15-00186.1 ◽

2016 ◽

Vol 64 (3) ◽

pp. 513-522 ◽

Cited By ~ 10

Author(s):

Nicole E Tautges ◽

Jessica R Goldberger ◽

Ian C Burke

Keyword(s):

United States ◽

Weed Control ◽

Weed Management ◽

Binary Logistic Regression ◽

Management Program ◽

Organic Farm ◽

Lack Of Information ◽

Program Diversity ◽

Certified Organic ◽

Organic Weed Management

A lack of information regarding weed control, relative to conventional systems, has left organic growers largely on their own when devising weed management systems for organic crops. As interest in organic weed management increases, researchers need more information regarding the type and number of weed control practices undertaken on organic farms. A survey of certified organic growers was conducted in five states in the northwest United States to identify organic weed management programs and what grower and farm-operation characteristics were factors in weed management program design. Three types of weed management programs, with varying diversity in weed control practices, were identified. Stepwise binary logistic regression indicated that the likelihood of an organic grower using a more-diverse weed management program increased if the grower engaged in grain production and as the number of crops produced on an organic farm operation in 1 yr increased. The probability of operating a more-diverse weed management program also increased as a grower's education level increased. Organic hectarage operated was positively correlated with weed management program diversity, and with the adoption of cultural controls. Additionally, awareness of weeds as a factor causing yield loss was correlated with increased weed management program diversity. An increased awareness among researchers of the differing needs and abilities of organic growers in managing weeds on their farms will improve communication and outreach efforts when assisting growers with designing organic weed management programs.

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A Multy-Year Study Reveals the Importance of Residual Herbicides on Weed Control in Glyphosate-Resistant Soybean

Planta Daninha ◽

10.1590/s0100-83582018360100039 ◽

2018 ◽

Vol 36 (0) ◽

Cited By ~ 2

Author(s):

A.L. NUNES ◽

J. LORENSET ◽

J.E. GUBIANI ◽

F.M. SANTOS

Keyword(s):

Field Study ◽

Weed Control ◽

Weed Management ◽

Crop Residues ◽

Residual Effect ◽

Soybean Cultivar ◽

Weed Species ◽

Soybean Yield ◽

Herbicide Treatments

ABSTRACT: A 3-year field study was conducted to assess the potential for using pre-emergent (PRE) herbicides tank mixed with glyphosate as a means of controlling weed species in soybean. In 2011/12, 2012/13 and 2013/14 growing sessions soybean cultivar Brasmax Apollo RR was planted under residues of rye. The herbicide treatments glyphosate (gly) (1,296 g a.i. ha-1), gly + S-metolachlor (1,296 + 1,920), gly + imazaquin (1,296 +161), gly + pendimethalin (1,296 + 1,000), gly + metribuzin (1,296 + 480), gly + 2.4-D amine (1,296 + 1,209) was applied in pre-emergence (PRE) over rye crop residues two days before soybean sowing. In addition, full season weed-free and weedy control plots were included. Gly + S-metolachlor and gly + pendimethalin reduced the horseweed density from 48 to 3 and 6 plants m-2, respectively. The mix containing gly + metribuzin and gly + 2.4-D amine and gly applied alone had no effect in the horseweed control. The mix containing gly + metribuzin, gly + 2.4-D amine, gly + imazaquin and gly applied alone had no effect in the crabgrass control. In contrast gly + S-metolachlor and gly + pendimethalin reduced the crabgrass density from 70 to 0 and 1 plant m-2, respectively. The soybean yield was higher with weed-free, S-metolachlor and metribuzin treatments. The use of an herbicide with residual effect had impact on weed management and soybean yield. In conclusion, a greater control of horseweed and crabgrass occurred when S-metolachlor or pendimethalin was applied PRE.

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The Impact of Weeding Regime, Planting Density, and Growth Habits on Watermelon Yield in an Organic System

HortTechnology ◽

10.21273/horttech04311-19 ◽

2019 ◽

Vol 29 (5) ◽

pp. 571-577

Author(s):

Suzanne P. Stone ◽

George E. Boyhan ◽

W. Carroll Johnson

Keyword(s):

United States ◽

Weed Control ◽

Growth Habit ◽

Southeastern United States ◽

Weed Suppression ◽

Planting Density ◽

Separate Experiment ◽

Organic System ◽

Growth Habits ◽

The Impact

The southeastern United States produces 50% of U.S. conventional watermelon (Citrullus lanatus) but only 7% of U.S. organic watermelon. Weeds are a major threat to watermelon yield in the southeastern United States, and organic weed control is estimated to cost 20-times more than conventional herbicide programs. The objectives of this study were to determine the optimal weed control regime to reduce hand-weeding costs while maintaining yield and to compare the weed suppression of two watermelon types with differing growth habits in an organic system. In 2014 and 2015, watermelon plots were randomly assigned to the following treatments in a factorial arrangement: vine or compact growth habit; 1.0- or 0.5-m in-row spacing; and weekly weed control (kept weed-free by hoeing and hand-pulling weeds) for 0, 4, or 8 weeks after transplanting (WAT). At the time of the watermelon harvest, not weeding resulted in average total weed densities of 86.6 and 87.0 weeds/m2, and weeding for 4 WAT resulted in average total weed densities of 26.4 and 7.0 weeds/m2 in 2014 and 2015, respectively. Nonetheless, weeding for 4 WAT resulted in watermelon yields and fruit counts comparable to those of weeding for 8 WAT during both years. This partial-season weeding regime resulted in 67% and 63% weeding cost reductions for vine and compact plants, respectively, in 2014, and a 43% reduction for both growth habit types in 2015. In 2015, a separate experiment that evaluated weeding regimes that lasted 0, 1, 2, 3, 4, and 8 WAT found that yields resulting from weeding for 3 WAT were greater than those resulting from weeding for 2 WAT. However, the yields did not differ when weeding was performed for 4 WAT and 8 WAT.

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Cultivation and Reduced-Rate Herbicides Weed Control in Sugarbeet Grown for Biofuel

Weed Technology ◽

10.1017/wet.2018.61 ◽

2018 ◽

Vol 32 (6) ◽

pp. 726-732

Author(s):

W. Carroll Johnson ◽

Theodore M. Webster ◽

Timothy L. Grey ◽

Xuelin Luo

Keyword(s):

United States ◽

Weed Control ◽

Southeastern United States ◽

Integrated System ◽

Cool Season ◽

Evening Primrose ◽

Limited Role ◽

Reduced Rate ◽

Main Effects ◽

Sugarbeet Yields

AbstractSugarbeet, grown for biofuel, is being considered as an alternate cool-season crop in the southeastern United States. Previous research identified ethofumesate PRE and phenmedipham + desmedipham POST as herbicides that controlled troublesome cool-season weeds in the region, specifically cutleaf evening-primrose. Research trials were conducted from 2014 through 2016 to evaluate an integrated system of sweep cultivation and reduced rates of ethofumesate PRE and/or phenmedipham+desmedipham POST for weed control in sugarbeet grown for biofuel. There were no interactions between the main effects of cultivation and herbicides for control of cutleaf evening-primrose and other cool-season species in two out of three years. Cultivation improved control of cool-season weeds, but the effect was largely independent of control provided by herbicides. Of the herbicide combinations evaluated, the best overall cool-season weed control was from systems that included either a 1/2X or 1X rate of phenmedipham+desmedipham POST. Either rate of ethofumesate PRE was less effective than phenmedipham+desmedipham POST. Despite improved cool-season weed control, sugarbeet yield was not affected by cultivation each year of the study. Sugarbeet yields were greater when treated with any herbicide combination that included either a 1/2X or 1X rate of phenmedipham+desmedipham POST compared with either rate of ethofumesate PRE alone or the nontreated control. These results indicate that cultivation has a very limited role in sugarbeet grown for biofuel. The premise of effective weed control based on an integration of cultivation and reduced herbicide rates does not appear to be viable for sugarbeet grown for biofuel.

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