Chemical weed control in lupins

The response of weeds and narrow-leaved lupins (Lupinus angustifolius) to a number of pre-planting, pre-emergence and post-emergence applied herbicides was evaluated in six field trials between 1970 and 1973. Applied six weeks post-emergence, fluometuron and propazine at 0.75, 1.5 and 3.0 kg, carbetamide at 1.5, 2.0 and 3.0 kg, simazine at 1.5 and 3.0 kg, and chlortoluron at 3.0 kg a.i. ha-1 gave good control of annual weeds present. Only carbetamide 1.5, 2.0 and 3.0 kg, propazine 0.75 and 1.5 kg and simazine 1.5 kg a.i. ha-1 increased grain yield. Decreasing yield with increasing dose rate in the case of fluometuron and propazine in this situation suggested some crop toxicity. Applied pre-planting and incorporated, alachlor 1.0 and 2.0 kg, di-allate 0.84 kg, nitralin 0.6 and 1.2 kg and trifluralin 0.56 kg a.i. ha-1 gave good grass control and, in general, increased yield. They had no effect on the majority of broadleaf species present. Applied pre-emergence, alachlor, propazine and simazine at 1.0 and 2.0 kg, fluometuron at 1.0 to 4.0 kg and pronamide at 0.8 and 1.6 kg a.i. ha-1 in general gave good weed control and increased grain yield. All except alachlor affected both grasses and broadleaf species. The results, however, were seriously affected by rainfall incidence. The results are discussed in terms of the response to incorporation, rainfall incidence and temperature on the activity of specific herbicides.

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Evaluating the EPA's Comparative Product Performance Testing Guidelines for Herbicides in Snap Bean (Phaseolus vulgaris)

Weed Technology ◽

10.1017/s0890037x00043712 ◽

1998 ◽

Vol 12 (2) ◽

pp. 215-222

Author(s):

Robin R. Bellinder ◽

Marija Arsenovic ◽

Jonathan J. Kirkwyland ◽

Russell W. Wallace

Keyword(s):

Weed Control ◽

Environmental Protection Agency ◽

Performance Testing ◽

Good Control ◽

Field Trials ◽

Weed Species ◽

Snap Bean ◽

Common Lambsquarters ◽

Redroot Pigweed ◽

Product Comparison

Following suggested guidelines developed by the Environmental Protection Agency (EPA), comparative snap bean herbicide performance field trials were conducted from 1993 to 1995 in New York. Data were obtained on crop injury, weed control, and weed biomass, and crop yield, quality, and losses during harvest. Trifluralin, EPTC, and pendimethalin applied preplant incorporated (PPI) and applications of metolachlor applied preemergence (PRE) provided less than adequate control of redroot pigweed, common lambsquarters, and hairy galinsoga. Cultivation improved weed control with PPI and PRE applications. Metolachlor + fomesafen PRE provided good control of hairy galinsoga, adequate redroot pigweed control, and marginal control of common lambsquarters. Fomesafen applied postemergence (POST), combinations of metolachlor applied PRE with fomesafen or bentazon applied POST, and fomesafen + bentazon applied POST adequately controlled the three weed species without cultivation. Herbicide treatments had little measurable impact on snap bean quality or losses during harvest. Information from product comparison trials may be useful in developing recommendations for growers but may prove less than adequate in providing data necessary for a thorough evaluation of the relative benefits of individual herbicides as intended by EPA guidelines. Difficulties were encountered in following the guidelines, and costs of conducting the product comparison trials for a single crop in one growing region exceeded $90,000 over 3 yr.

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Differential responses of two cowpea (Virgina unguiculata L.Walp.) genotypes to pre-emergence herbicides in the savannah woodland and rainforest agroclimatic regions of Sierra Leone

World Journal of Advanced Research and Reviews ◽

10.30574/wjarr.2021.10.1.0161 ◽

2021 ◽

Vol 10 (1) ◽

pp. 343-355

Author(s):

Dan David. Quee ◽

Philip Jimia. Kamanda ◽

Musa Decius. Saffa ◽

Johnny Ernest. Norman

Keyword(s):

Grain Yield ◽

Sierra Leone ◽

Weed Control ◽

Dry Weight ◽

Field Trials ◽

Variable Cost ◽

Control Techniques ◽

Net Returns ◽

Preemergence Herbicides ◽

Savannah Woodland

Field trials were conducted in savannah woodland (Njala) and rainforest (Serabu) agroclimatic regions of Sierra Leone during 2016 second cropping season to assess different preemergence herbicides techniques that is efficient, cost effective and environmentally safe in cowpea production. The experiment consisted of 20 treatments which included 2 cowpea genotypes (slipea 4 and slipea 5) and 10 different weed control techniques viz: butachlor 50% emulsifiable concentrate (EC), double force®, power force® applied as preemergence herbicides at 2, 4 and 6 L ha-1, respectively and weedy check. The treatments were laid out in a strip-plot design arranged in a factorial system with three replications. The results of this study revealed that the application of power force® at 6 L ha-1 recorded the highest phytotoxic effect, lowest weed dry weight, number of pods per plant and grain yield, highest total variable cost, lowest gross and net returns. Furthermore, butachlor 50% EC at 2 L ha-1 closely followed by double force® at 6 L ha-1 resulted in maximum grain yield, gross and net returns compared to the rest of the other weed control techniques. Thus, it is concluded that butachlor 50% EC at 2 L ha-1 was more economical, profitable and beneficial than other control treatments in the production of cowpea genotypes in the savannah woodland and rainforest agroclimatic regions of Sierra Leone. Conclusively, the relationship between phytotoxicity and grain yield indicates that the higher the grain yield the lower the phytotoxic effects of the chemicals.

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Weed Control in Cowpea (Vigna unguiculata) in the Humid Tropics

Weed Science ◽

10.1017/s0043174500040698 ◽

1982 ◽

Vol 30 (4) ◽

pp. 331-334 ◽

Cited By ~ 7

Author(s):

I. Okezie Akobundu

Keyword(s):

Grain Yield ◽

Weed Control ◽

Vigna Unguiculata ◽

Humid Tropics ◽

Yield Reduction ◽

Crop Injury ◽

Annual Grasses ◽

Annual Weeds

At least two weedings within the first 5 weeks after sowing are necessary to minimize yield reduction caused by weeds in cowpea [Vigna unguiculata(L.) Walp.]. During a 3-yr study, a preemergence application of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] at 2.0 to 3.0 kg/ha, DCPA (dimethyl tetrachloroterephthalate) at 10.0 kg/ha, or pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine] at 2.0 or 2.5 kg/ha controlled most annual grasses effectively. Itchgrass (Rottboellia exaltataL.) was controlled with pendimethalin at 2.5 kg/ha, but metolachlor had no effect on this weed. These herbicides caused no crop injury and cowpea grain yield was as good as in the handweeded and weed-free plots. Alachlor [2-chloro-2′, 6′-diethyl-N-(methoxymethyl) acetanilide] applied preemergence at 2.0 kg/ha was effective against annual weeds, but was phytotoxic to cowpea.

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Efficacy of Reduced Rates of Soil-Applied Dimethenamid-P and Pendimethalin Mixture Followed by Postemergence Herbicides in Maize

Agriculture ◽

10.3390/agriculture10050163 ◽

2020 ◽

Vol 10 (5) ◽

pp. 163

Author(s):

Robert Idziak ◽

Zenon Woznica

Keyword(s):

Grain Yield ◽

Weed Control ◽

Negative Impact ◽

Control Program ◽

Field Trials ◽

Economic Benefits ◽

Net Return ◽

Herbicide Mixture ◽

Reduced Rate ◽

Postemergence Herbicides

Field trials were conducted with preemergence dimethanamid-P + pendimethalin (D + P; 850 + 1000 g·ha−1) and reduced rates (637.5 + 750 g·ha−1 and 452 + 500 g·ha−1, 75% and 50% of label rate), followed by strongly reduced rates of postemergence herbicides nicosulfuron + rimsulfuron + dicamba (N + R + D; 4 + 15.6 + 93.5 g·ha−1, 50%), tembotrione (T; 33 g·ha−1, 50%), mesotrione + nicosulfuron (M + N; 37.5 + 15 g·ha−1, 50%), foramsulfuron + iodosulfuron (F + J; 7.5 + 0.25 g·ha−1, 20%), and nikosulfuron (N; 15 g·ha−1, 33%) applied with methylated seed oil (MSO; 1.0 L·ha−1) and ammonium nitrate (AMN; 2 kg·ha−1) on 3–5 leaves of maize to assess weed control, grain yield, and economic net return. Reduced rate of soil-applied herbicide followed by reduced rates of any postemergence herbicides applied with adjuvants was the most efficacious weed control program, provided the highest grain yield of maize and similar or higher economic net return, despite 44 to 48% lower herbicide input than the program based on soil-applied herbicide mixture only. It brings not only notable economic benefits but also less negative impact on the environment.

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Evaluation of Glufosinate-Resistant Corn (Zea mays) and Glufosinate: Efficacy on Annual Weeds

Weed Technology ◽

10.1017/s0890037x00042093 ◽

1999 ◽

Vol 13 (4) ◽

pp. 691-696 ◽

Cited By ~ 17

Author(s):

Ronald F. Krausz ◽

George Kapusta ◽

Joseph L. Matthews ◽

John L. Baldwin ◽

Jason Maschoff

Keyword(s):

Zea Mays ◽

Grain Yield ◽

Weed Control ◽

Field Studies ◽

Single Application ◽

Common Lambsquarters ◽

Giant Foxtail ◽

Annual Weeds ◽

Weed Emergence

Field studies were conducted in 1996 and 1997 at Belleville and Pawnee, IL, to evaluate single and sequential applications of glufosinate on tolerance of glufosinate-resistant corn and annual weed control. Glufosinate caused 0 to 13% corn injury 7 days after treatment (DAT) and 0 to 6% corn injury 28 DAT. Injury was characterized as stunting with glufosinate. Glufosinate at 400 to 1,200 g ai/ha did not reduce final corn height or grain yield. At Pawnee in both years and at Belleville in 1996, a single application of glufosinate at 400 g/ha controlled giant foxtail, velvetleaf, ivyleaf morningglory, and common lambsquarters 85 to 100%. At Belleville in 1997, sequential applications of glufosinate provided greater weed control (87 to 100%) than a single application (0 to 63%) because of weed emergence after application. Weed control with a single application of glufosinate or with nicosulfuron plus bromoxynil was similar at both locations. Height and grain yield of glufosinate-resistant corn were not different from that of glufosinate-susceptible corn (isoline of glufosinate-resistant corn).

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Weed control efficacy of hoe weeding and commercially formulated mixture of metolachlor + prometryn herbicide under maize production in soil amended with biochar

Agricultura tropica et subtropica ◽

10.2478/ats-2019-0008 ◽

2019 ◽

Vol 52 (2) ◽

pp. 73-78

Author(s):

Olusegun Raphael Adeyemi ◽

David Obaloluwa Hosu ◽

Patience Mojibade Olorunmaiye ◽

Adeniyi Adebowale Soretire ◽

Joseph Aremu Adigun ◽

...

Keyword(s):

Grain Yield ◽

Weed Control ◽

Block Design ◽

Maize Yield ◽

Field Trials ◽

Growth And Yield ◽

Control Methods ◽

Maize Production ◽

Randomized Design ◽

Manual Weeding

Abstract Successful cultivation of maize depends largely on efficient weed control, adequate supply of essential nutrients and sufficient soil moisture. Screenhouse and field trials were conducted at the Teaching and Research Farm of the Federal University of Agriculture, Abeokuta, Nigeria during the early and late cropping season of 2013 to evaluate effects of biochar integrated with manual weeding and pre-emergence herbicides on weed control efficiency and productivity of maize. The screenhouse trial was a 6 × 5 factorial experiment fitted into Completely Randomized Design in three replicates. The two factors were biochar: 0, 2, 4, 6, 8 and 10 t ha−1 and weed control methods: weedy check, hoe weeding at 6 Weeks After Sowing (WAS), hoe weeding at 3, 6, and 9 WAS, pre-emergence herbicide application (Codal Gold) at 1.0 and 2.0 kg a.i./ha−1. The field trial was laid out in split-plot arrangement fitted into Randomized Complete Block Design with three replicates. The three main treatments plots on the field consisted of the optimum rates of biochar obtained in the screenhouse (10 t ha−1) compared with 20 t ha−1 and 0 t ha−1 which served as the control. The sub-plots treatments consisted of weed control methods used in the screen house experiment. Data were collected on grain yield and weed dry matter. The result showed that biochar at 10 and 20 t ha−1 in the screenhouse and field trials, respectively, resulted in significantly (P < 0.05) higher grain yield compared with other rates tested. Highest grain yield was obtained in pots hoe weeded thrice at 3, 6 and 9 WAS. Whereas similar grain yield was recorded in plot weeded once at 6 WAS and that hoe weeded at 3, 6 and 9 WAS in the field experiment. Biochar application of 20 t ha−1 gave optimum maize yield. Among the weed control treatments manual weeding either at 6 WAS or at 3, 6 and 9 WAS recorded the highest grain yields. Therefore, incorporation of biochar with either preemergence herbicide or manual hoe weeding would enhance the growth and yield of maize.

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Replace of the EPOST glyphosate with pre herbicides and application of different LPOST glyphosate rates for weed control in established vineyard

Acta agriculturae Slovenica ◽

10.14720/aas.2020.116.2.1910 ◽

2020 ◽

Vol 116 (2) ◽

pp. 299

Author(s):

Zvonko PACANOSKI ◽

Krum BOŠKOV ◽

Arben Beni MEHMETI

Keyword(s):

Weed Control ◽

Cynodon Dactylon ◽

Lolium Multiflorum ◽

Chenopodium Album ◽

Field Trials ◽

Early Summer ◽

Xanthium Strumarium ◽

Summer Period ◽

Herbicide Treatments ◽

Annual Weeds

Two-year field trials were conducted at two winegrowing districts (Kavadarci and Skopje in 2016 and 2017) to evaluate wheather oxyfluorfen, pendimethalin and flazasulfuron can replace early post-emergence (EPOST) application of glyphosate in established vineyard until its application in early summer period. The weed vegetation in vineyards in both years was consisted mainly of Chenopodium album L., Setaria viridis (L). Beauv., Papaver rhoeas L., Xanthium strumarium L., Lolium multiflorum Lam., Sorghum halepense (L.) Pers. and Cynodon dactylon (L.) Pers. Pendimethalin, oxyfluorfen and flazasulfuron efficiently reduced predominant annual weeds and S. halepense seedlings in 2017, but not in 2016. PRE herbicides, regardless year, had no significant effect on C. dactylon. Opposite, the efficacy of EPOST applied glyphosate was significantly lower in 2017 compared to 2016. LPOST glyphosate applied at 2.0 l ha-1 provided at least 94 % control of dominant annual broadleaf and grass weeds. LPOST application of glyphosate at 2.0 l ha-1 and glyphosate at 2.0 and 4.0 l ha-1 resulted in unsatisfactory weed control of predominant perennial S. halepense, and C. dactylon, respectively. LPOST glyphosate applied at 4.0 l ha-1 provided control of S. halepense by 84 % or more. LPOST glyphosate applied at 8.0 l ha-1 reduced the amount of S. halepense and C. dactylon at least 97 %. Grapevine yield of both varieties was not lower in all herbicide treatments in 2016 compared with 2017. However, yield in the PRE herbicide treatments fb 2.0 and 4.0 l ha-1 glyphosate was collectively 15-19 % and 17-19 % lower compare to PRE herbicide treatments fb 8.0 l ha-1 glyphosate and standard two applications of glyphosate, respectively for both years and districts. No impacts to grapevine growth were observed from PRE herbicide treatments at either district

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Weed control and productivity of maize (Zea mays L.) in Malete, Kwara State of Nigeria

Agricultura tropica et subtropica ◽

10.2478/ats-2020-0007 ◽

2020 ◽

Vol 53 (2) ◽

pp. 63-71

Author(s):

Emmanuel Oyamedan Imoloame

Keyword(s):

Grain Yield ◽

Weed Control ◽

Control Method ◽

Block Design ◽

Field Trials ◽

State University ◽

Application Rates ◽

Hand Weeding ◽

Statistical Analysis Software ◽

Range Test

AbstractThe need to determine the minimum application rates of commonly used herbicides in Malete and the Guinea savanna of Nigeria for effective weed control and higher grain yield of maize, triggered this study. Therefore, field trials were conducted at the Teaching and Research Farm of Kwara State University, Malete, to determine the weed control method that will be more effective in controlling weeds and give higher grain yield and cash returns in the production of maize. The experiment consisted of 9 treatments viz: primextra (metolachlor plus atrazine) + 2,4-D at 1.5 + 1.5 kg active ingredient (a.i.).ha−1, primextra + 2,4-D at 2.0 + 2.0 kg a.i. ha−1, primextra + 2,4-D at 2.5 + 2.5 kg ha−1, primextra + nicosulfuron at 1.5 + 0.03 kg a.i. ha−1, primextra + nicosulfuron at 2.0 + 0.05 kg a.i. ha−1, primextra + niconsulfuron at 2.5 + 0.07 kg a.i. ha−1, primextra at 1.5 kg a.i. ha−1 + one Supplementary Hoe Weeding (SHW) at 6 Weeks After Sowing (WAS), two hand weeding at 3 and 6 Weeks After Sowing (WAS) and a weedy check. These treatments were laid out in randomised complete block design (RCBD) with three replicates. Data collected were subjected to analysis of variance using Statistical Analysis Software (SAS) package, after which means were separated using Duncan’s Multiple Range Test (DMRT). Results showed that treatment combinations of primextra + one SHW at 6 WAS, two hoe weeding at 3 and 6 WAS, primextra + 2,4-D at 2.0 + 2.0 kg a.i. ha−1 and primextra + nicosulfuron at 2.0+0.05 kg a.i. ha−1 gave effective weed control, higher grain yield and cash returns. Therefore, primextra at 1.5 kg a.i. ha−1 + one SHW at 6 WAS, primextra +2,4-D at 2.0 + 2.0 kg a.i. ha−1 and primextra + nicosulfuron at 2.0 + 0.05 kg a.i. ha−1 are recommended to farmers as alternative to two hoe weeding at 3 and 6 WAS.

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Efficacy and crop selectivity of saflufenacil alone and with partner herbicides for weed control in maize

New Zealand Plant Protection ◽

10.30843/nzpp.2011.64.6012 ◽

2011 ◽

Vol 64 ◽

pp. 133-141 ◽

Cited By ~ 1

Author(s):

M.R. Trolove ◽

A. Rahman ◽

G.C. Hagerty ◽

T.K. James

Keyword(s):

Weed Control ◽

Chenopodium Album ◽

Negative Relationship ◽

Good Control ◽

Field Trials ◽

Effective Control ◽

Visual Damage ◽

Strong Negative Relationship ◽

Damage Symptoms

The recently developed herbicide saflufenacil was evaluated in six field trials between 2008 and 2011 for weed control in maize (Zea mays) crops Trial sites varied considerably in soil characteristics and weed spectrum No phytotoxicity or visual damage symptoms were observed in any of the six cultivars planted When used alone at 70 or 105 g ai/ha saflufenacil provided effective control of annual broadleaf weeds including atrazine and dicambaresistant fathen (Chenopodium album) but had little activity on grass weeds In combination with acetochlor both rates of saflufenacil provided good control of annual grass and broadleaf weeds in all but one trial In crops with a high weed pressure especially grass weeds a follow up postemergence herbicide would be required to maximise control Combinations of saflufenacil with up to 1200 g ai/ha of dimethenamidp were generally less effective than with acetochlor A strong negative relationship was evident between weed density and maize silage or grain yields

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Why Early Season Weed Control Is Important in Maize

Weed Science ◽

10.1614/ws-d-11-00183.1 ◽

2012 ◽

Vol 60 (3) ◽

pp. 423-430 ◽

Cited By ~ 31

Author(s):

Eric R. Page ◽

Diego Cerrudo ◽

Philip Westra ◽

Mark Loux ◽

Kenneth Smith ◽

...

Keyword(s):

Grain Yield ◽

Weed Control ◽

Dry Matter ◽

Yield Loss ◽

Treatment Plant ◽

Field Trials ◽

Yield Potential ◽

Dry Matter Accumulation ◽

State University ◽

Weed Interference

Control of early-emerging weeds is essential to protect the yield potential of maize. An understanding of the physiological changes that occur as a result of weed interference is required to address variability in yield loss across sites and years. Field trials were conducted at the University of Guelph (UG), the Ohio State University (OSU), and Colorado State University (CSU) during 2009 and 2010. There were six treatments (season-long weedy and weed-free, and weed control at the 1st-, 3rd-, 5th-, and 10th-leaf-tip stages of maize development) and 20 individual plants per plot were harvested at maturity. We hypothesized that, as weed control was delayed, weed interference in the early stages of maize development would increase plant-to-plant variability in plant dry-matter accumulation, which would result in a reduction of grain yield at maturity. The onset of the critical period for weed control (CPWC) occurred on average between the third and fifth leaf tip stages of development (i.e., V1 to V3, respectively). Rate of yield loss following the onset of the CPWC ranged from 0.05 MG ha−1d−1at UG 2009 to 0.22 MG ha−1d−1at CSU 2010 (i.e., 0.5 and 1.6% d−1, respectively). On average, reductions in kernel number per plant accounted for approximately 65% of the decline in grain yield as weed control was delayed. Biomass partitioning to the grain was stable through early weed removal treatments, increased and peaked at the 10th-leaf-tip time of control, and decreased in the season-long weedy treatment. Plant-to-plant variability in dry matter at maturity and incidence of bareness increased as weed control was delayed. As weed control was delayed, the contribution of plant-to-plant variability at maturity to the overall yield loss was small, relative to the decline of mean plant dry matter.

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