Evaluation of some pre and postemergence herbicides for weed control in yacon

Weed control was investigated in yacon (Smallanthus sonchifolius Asteraceae) a herbaceous perennial that produces edible tubers Eight preemergence (alachlor acetochlor simazine diuron pendamethalin dimethanamid methabenzthiazuron and metribuzin) and two postemergence (linuron and methabenzthiazuron) herbicides were evaluated in field trials at Pukekohe All preemergence herbicides except metribuzin were tolerated by yacon but the best weed control was achieved with acetochlor metribuzin and dimethanamid Weeds in the untreated control caused a 62 reduction (Plt;005) in root weight relative to acetochlor alachlor metribuzin and dimethanamid The postemergence herbicides were both phytotoxic to yacon top growth but the plants subsequently recovered and plant crown production at harvest was not reduced relative to the control (P>005)

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Optimising time of planting and herbicide aplication for control of problem weeds in maize

New Zealand Plant Protection ◽

10.30843/nzpp.2007.60.4598 ◽

2007 ◽

Vol 60 ◽

pp. 183-188

Author(s):

T.K. James ◽

A. Rahman ◽

M. Trolove

Keyword(s):

Weed Control ◽

Residual Activity ◽

Good Control ◽

Field Trials ◽

Application Time ◽

Annual Grass ◽

Weed Species ◽

Long Period ◽

Preemergence Herbicides ◽

Postemergence Herbicides

Field trials in Waikato Bay of Plenty and Manawatu investigated the efficacy of pre and postemergence herbicides for weed control in maize crops planted early mid or late season with prior cultivation or into a stale seedbed Achieving good control of broadleaf weeds was easier than for annual grass weeds Some weed species germinated over a long period from spring to summer months The residual activity of preemergence herbicides was not sufficient for seasonlong control of such weeds in the early and mid planted crops and a postemergence herbicide was essential to control them and to maintain grain yields When grass weeds were dominant the pre and postemergence combination still did not provide season long control in the early plantings In late planted crops weed control was also poor in the absence of a postemergence herbicide even though few weeds were present at the postemergence application time The weed seedbank was reduced where good weed control was achieved

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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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Tolerance of Hooker’s Evening Primrose Transplants to Preemergence Herbicides

HortTechnology ◽

10.21273/horttech.23.1.24 ◽

2013 ◽

Vol 23 (1) ◽

pp. 24-27

Author(s):

Amber N. Bates ◽

Gerald M. Henry ◽

Cynthia B. McKenney

Keyword(s):

Weed Control ◽

Untreated Control ◽

Growth Index ◽

Belowground Biomass ◽

Oenothera Biennis ◽

Potential Yield ◽

Evening Primrose ◽

Phytotoxic Effect ◽

Texas Tech University ◽

Preemergence Herbicides

No research has investigated the phytotoxic response of hooker’s evening primrose (Oenothera elata) plug transplants to preemergence herbicides. Varied phytotoxic responses of common evening primrose (Oenothera biennis) to preemergence herbicides suggest that options may exist for the safe control of weeds present within hooker’s evening primrose when grown as an agronomic field crop. Enhanced weed control during early establishment may reduce competition for water and nutrients as well as increase seed yield and oil content. Therefore, the objective of this research was to determine the phytotoxic effect of preemergence herbicides on hooker’s evening primrose plug transplants grown in the greenhouse. Research was conducted in 2010 and 2011 at the Plant and Soil Science greenhouse complex at Texas Tech University in Lubbock, TX. Herbicide treatments were applied on 13 July 2010 and 5 Apr. 2011 and consisted of oxadiazon at 3 lb/acre, isoxaben at 0.5 lb/acre, oryzalin at 2 lb/acre, prodiamine at 1.5 lb/acre, dithiopyr at 0.5 lb/acre, s-metolachlor at 1.8 lb/acre, pendimethalin at 0.6 lb/acre, and isoxaben + trifluralin at 2.5 lb/acre. One 4-month-old hooker’s evening primrose plug (2 inches wide) was transplanted into each pot (3 gal) 2 days after treatment (DAT). Dithiopyr and s-metolachlor treatments exhibited similar lack of phytotoxicity as the untreated control 7 DAT. Phytotoxicity ≥13% was observed for trifluralin + isoxaben, pendimethalin, prodiamine, oryzalin, isoxaben, and oxadiazon 7 DAT, with the highest level of phytotoxicity (24%) exhibited by trifluralin + isoxaben treatments. Hooker’s evening primrose phytotoxicity decreased (plants grew out of the damage) for all treatments except trifluralin + isoxaben, pendimethalin, and oryzalin 28 DAT. Oryzalin (16%) and trifluralin + isoxaben (60%) were the only two treatments that did not exhibit similar phytotoxicity to the untreated control 28 DAT. There were no significant differences in aboveground or belowground biomass nor plant growth index (PGI) of any of the treatments when compared with the untreated control 28 DAT. Based upon the results of this trial, pendimethalin, prodiamine, dithiopyr, s-metolachlor, oryzalin, isoxaben, and oxadiazon may be used for preemergence weed control in hooker’s evening primrose without causing excessive phytotoxicity (>20%), potential yield loss, or both. Trifluralin + isoxaben treatments exhibited 60% hooker’s evening primrose phytotoxicity 28 DAT, which resulted in too low of an initial plant stand to warrant use.

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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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Preemergence Herbicides for Potential Use in Potato Production

Weed Technology ◽

10.1614/wt-d-12-00023.1 ◽

2012 ◽

Vol 26 (4) ◽

pp. 731-739 ◽

Cited By ~ 6

Author(s):

Rick A. Boydston ◽

Joel Felix ◽

Kassim Al-Khatib

Keyword(s):

Weed Control ◽

Potato Production ◽

Field Trials ◽

Common Lambsquarters ◽

Hairy Nightshade ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Preemergence Herbicides ◽

Potential Use

Field trials were conducted in 2009 and 2010 near Paterson, WA and Ontario, OR to evaluate weed control and potato tolerance to PRE-applied pyroxasulfone, saflufenacil, and KSU12800 herbicides. Pyroxasulfone at 0.09 to 0.15 kg ai ha−1and saflufenacil at 0.05 to 0.07 kg ai ha−1applied PRE alone or in tank mixes with several currently labeled herbicides did not injure potatoes at either site in both years. KSU12800 at 0.15 kg ai ha−1injured potatoes from 18 to 26% for a period of about 4 wk after emergence at Ontario both years. In addition, KSU12800 at 0.29 and 0.45 kg ha−1injured potatoes from 17 to 38% at 17 d after treatment (DAT) at Paterson in 2009. Pyroxasulfone at 0.15 kg ha−1controlled barnyardgrass, hairy nightshade, and redroot pigweed 96% or greater, but control of common lambsquarters was variable. Saflufenacil at 0.07 kg ha−1provided greater than 93% control of common lambsquarters, hairy nightshade, and redroot pigweed at both sites in 2010. KSU12800 at 0.15 kg ha−1controlled common lambsquarters, hairy nightshade, and redroot pigweed 99% or more at Ontario, but only 87 to 93% at Paterson in 2010. These herbicides did not reduce yield of U.S. no. 1 tubers or total tuber yields compared to standard labeled herbicide treatments when weed control was adequate.

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Response of Soybeans (Glycine max) to Planting in Untilled, Weedy Seedbed on Clay Soil

Weed Science ◽

10.1017/s0043174500068612 ◽

1983 ◽

Vol 31 (1) ◽

pp. 93-99 ◽

Cited By ~ 33

Author(s):

Larry G. Heatherly ◽

C. Dennis Elmore

Keyword(s):

Glycine Max ◽

Control Systems ◽

Weed Control ◽

Mississippi River ◽

Dry Conditions ◽

Sida Spinosa ◽

Seedbed Preparation ◽

Prickly Sida ◽

Preemergence Herbicides ◽

Postemergence Herbicides

Soybeans [Glycine max(L.) Merr.] were planted in an untilled, stale seedbed and conventionally tilled seedbed of Sharkey clay (Vertic Haplaquept) at Stoneville, Mississippi, in 1979 and 1980 to determine the feasibility of the stale -seedbed approach for soybean production in the Mississippi River Delta. Chemical weed control included applications of preplant, preemergence, and postemergence herbicides. Prickly sida (Sida spinosaL.) was the dominant weed in all tillage and weed-control systems. Perennial species were observed at harvest mostly in the stale - seedbed plots. Preemergence herbicides reduced the total weight of weeds per plot. Conventional seedbed preparation caused delays in planting of 3 weeks or more. In the presence of adequate soil moisture, yields of ‘Bedford,’ ‘Tracy’, and ‘Bragg’ cultivars from the stale - seedbed planting and areas that had been treated preemergence were always equal to or greater than yields from the tilled - seedbed plantings and areas that had been treated postemergence. In 1980, the hot, dry conditions of the growing season apparently negated any effect from either earlier planting or preemergence vs. post-emergence weed control.

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Weed Control in Field Nurseries

HortTechnology ◽

10.21273/horttech.13.1.0009 ◽

2003 ◽

Vol 13 (1) ◽

pp. 9-14 ◽

Cited By ~ 18

Author(s):

James E. Altland ◽

Charles H. Gilliam ◽

Glenn Wehtje

Keyword(s):

Weed Control ◽

Broad Spectrum ◽

Weed Management ◽

Weed Species ◽

Field Nursery ◽

Nursery Crops ◽

Herbicide Use ◽

Preemergence Herbicides ◽

Postemergence Herbicides ◽

Chemical Class

Herbicide use is an important component of weed management in field nursery crops. No single herbicide controls all weed species. Oxyfluorfen, simazine, and isoxaben are preemergence herbicides effective against broadleaf weeds. Oryzalin, pendimethalin, and prodiamine are effective in preemergence control of grasses and some small-seeded broadleaf weeds. Metolachlor is the only herbicide currently labeled for nursery crops that is effective in preemergence nutsedge (Cyperus) control. Fluazifop-butyl, sethoxydim, and clethodim are selective postemergence herbicides used for grass control. Glyphosate, paraquat, and glufosinate are nonselective postemergence herbicides used in directed spray applications for broad-spectrum weed control. Bentazon, halosulfuron, and imazaquin are effective postemergence nutsedge herbicides. These herbicides are discussed with respect to their chemical class, mode of action, labeled rates, and current research addressing their effectiveness in nursery crops.

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Optimal timing for post emergence applications of nicosulfuron for weed control in maize

New Zealand Plant Protection ◽

10.30843/nzpp.2006.59.4407 ◽

2006 ◽

Vol 59 ◽

pp. 250-254

Author(s):

T.K. James ◽

A. Rahman ◽

M. Trolove

Keyword(s):

Weed Control ◽

Ground Cover ◽

Field Trials ◽

Optimal Timing ◽

Grain Yields ◽

Growing Seasons ◽

Maize Plants ◽

Maize Grain ◽

Preemergence Herbicides ◽

The Impact

Field trials were conducted over three growing seasons to ascertain optimal timing for post emergence application of nicosulfuron in maize when no preemergence herbicides were used Nicosulfuron (60 g/ha) was applied at 1 to 7 weeks after maize emergence Dry matter and leaf area of maize plants grass and broadleaf weeds were determined at the time of treatment Maize grain yields were used as the major determinant to assess the impact of different timings of postemergence weed control The early season (weeks 13) weed control achieved with nicosulfuron was excellent but subsequent germination of weeds occurred In weeks 47 the larger weeds took longer to brown off and die back Results showed that both the biomass and ground cover of weeds were important in determining the duration of the optimal application window When weeds remained uncontrolled and achieved 100 ground cover grain yields were significantly reduced This occurred at weeks 3 5 and 6 after emergence in the three trials

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Use of Sulfentrazone (F6285) for Weed Management in Field-grown Ornamentals

HortScience ◽

10.21273/hortsci.31.4.661e ◽

1996 ◽

Vol 31 (4) ◽

pp. 661e-661

Author(s):

Kimberly B. Collins ◽

Leslie A. Weston ◽

Robert E. McNiel

Keyword(s):

Weed Control ◽

Weed Management ◽

Block Design ◽

Woody Species ◽

Field Trials ◽

Weed Species ◽

Ongoing Research ◽

Weed Interference ◽

Soil Activity ◽

Postemergence Herbicides

The nursery industry currently has few options for effective season-long weed control, because few soil persistent herbicides are registered for use in ornamentals. An herbicide that provides season-long weed control with minimal injury to ornamentals would be extremely beneficial because it would enable the nurseryman to produce high-quality ornamentals with minimal weed interference Sulfentrazone (F6285), a newly developed herbicide from the FMC Corp., has shown promising results for weed control in field trials with ornamentals. Additional, trials are needed to further evaluate sulfentrazone in hopes that it may be registered for use in ornamentals in the future. Our objectives are 1) to increase long-term weed management in ornamentals, including woody species and groundcover; 2) to evaluate rate structures of sulfentrazone and combinations, including preemergence and postemergence herbicides; 3) to evaluate sulfentrazone selectivity in weed species and in ornamentals; 4) to evaluate sulfentrazone mode of action in weed species; and 5) to measure the soil activity of sulfentrazone. To achieve the first three objectives, a randomized complete block design will be used to evaluate 10 woody species and 17 herbicide combinations. The response variables will be weed control and phytotoxicity ratings taken at 0, 4, 8, and 12 weeks after treatment. The results of this study will be used in ongoing research trials in an attempt to register sulfentrazone (F6285) for use in ornamentals.

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The Use of Preemergence Herbicides for Weed Control Around Young Coffee Seedlings

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v48i1.12970 ◽

1969 ◽

Vol 48 (1) ◽

pp. 25-31

Author(s):

Jaime González Ibáñez

Keyword(s):

Weed Control ◽

Root Weight ◽

Seedling Vigor ◽

Severe Stunting ◽

Plastic Bags ◽

Preemergence Herbicides

The preemergence herbicides Monuron, Diuron, Neburon, Simazine, Atrazine, Amizine, Fenac, Silvex, and DNBP were tested each at three dosages on the surface of soil planted to young coffee seedlings in plastic bags. In general, the best weed control was obtained by using Diuron at the rate of 2 pounds per acre, Neburon at the rate of 16 pounds per acre, Simazine at the rate of 2 pounds per acre, and Amizine at the rates of 2, 4, and 8 pounds per acre. Monuron at 8 pounds per acre caused severe stunting of coffee seedlings and the death of some. Root weight was greatly reduced. Diuron and Atrazine both tended to produce good seedling appearance, but reduced root weight. Fenac and Silvex caused malformed and stunted leaves in surviving coffee seedlings, and DNBP reduced coffee seedling vigor. Untreated checks grew poorly, and were the weediest at all times.

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