DOCSLIB.ORG

Sweet Corn Weed Control Evaluations on Mineral and Organic Soils

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Sweet Corn Weed Control Evaluations on Mineral and Organic Soils Proc. Fla. State Hort. Soc. 105:326-330. 1992. SWEET CORN WEED CONTROL EVALUATIONS ON MINERAL AND ORGANIC SOILS G. S. Crnko with atrazine, was the major herbicide used in sweet corn Seminole County Cooperative Extension Service grown in organic soils. Metolachlor, a related acetanilide IFAS, University of Florida herbicide, contains labeling restrictions for use on organic Sanford, FL 32773 soil (Stall, 1991). Pendimethalin has a label for use on sweet corn applied W. M. Stall preemergence or early postemergence in several states. Horticultural Sciences Department Sweet corn has been damaged when pendimethalin was IFAS, University of Florida applied preemergence in Florida. In initial studies pen Gainesville, FL 32611 dimethalin applied to sweet corn postemergence at the spike growth stage did not injure plants grown on mineral J. M. White soils. Central Florida Research and Education Center With the availability of limited preemergence her IFAS, University of Florida bicides, the use of postemergence herbicides may be in Sanford, FL 32771 creasing. Cultivation is used to control weeds between rows. However, grass and broadleaf weeds can become a Additional index words. Sweet corn, Zea mays var. rugosa, her great problem in the plant row. Sethoxydim and linuron bicides, metolachlor, pendimethalin, atrazine, bromoxynil, are both labeled for use as a directed spray. Tank-mixes pyridate, sethoxydim, linuron. of these materials had not been tested for control of both broadleaf weeds and grasses. Abstract Several herbicides were evaluated on a mineral soil Bromoxynil has a label for control of emerged broad in Gainesville and on an organic soil in Ze 11 wood, FL in 1991 leaf weeds on field corn and popcorn, but not on sweet and 1992 for weed control in sweet corn [Zea mays L. var. corn. The use of two new sulfonylurea herbicides, nicosul- rugosa Bonaf .)• Metolachlor and pendimethalin were applied fuion and primisulfuron is not recommended in sweet at several rates alone and tank-mixed with atrazine for corn due to the differential responses of sweet corn cul- preemergence control of weeds and evaluated for crop safety. tivars to these herbicides. Phytotoxicity with these two her Bromoxynil was applied alone and bromoxynil and pyridate bicides may also be enhanced when organophosphate in were tank-mixed with atrazine applied post over-the-top and secticides are used (Monks et al., 1992; Stall and Bewick, were evaluated for broadleaf weed control and crop safety. 1992). Sethoxydim, linuron and tank mixes of sethoxydim-linuron, The purpose of these studies was to evaluate potential and sethoxydim-atrazine were applied post-directed and herbicides for weed control and phytotoxicity on mineral were evaluated for crop safety and weed control. Metolachor and organic soils in Florida. and pendimethalin treatments did not cause crop toxicity and controlled grass weeds. Several broadleaf weeds were not effectively controlled season long, especially on the organic soils. Bromoxynil and pyridate applications effectively con Materials and Methods trolled the broadleaf weeds found in these fields with no Experiments on mineral soils were conducted at the damage to sweet corn. Sethoxydim, linuron and the tank Horticultural Unit, Gainesville, Florida during the Spring mixes applied post-directed did not provide any crop damage, of 1991 and 1992. Plots for both years were on 4 foot while controlling very large weeds. center beds in a randomized complete block design on a Pomona sand with 1.2 and 2.2 percent organic matter and Florida is the leading state in the nation in fresh market a pH of 6.5 and 6.8, respectively. sweet corn production. In the 1990-91 crop season, 51,700 Sweet corn 'SS-8701' and 'Dazzle' were planted 11 Apr. acres of sweet corn were planted in Florida. This is down 1991 and 6 Apr. 1992, respectively. Plots were fertilized at from 58-59,000 acres planted the previous three years planting and sidedressed once at a rate of 91-29-91 and (Freie and Young, 1991). 30-0-28, (N-P-K) pounds per acre, respectively. Overhead Control of weeds is a major problem in sweet corn pro irrigation was used as needed. duction. An average annual loss of potential production of Experiments on organic soils were carried out in grow 10% has been estimated per year in sweet corn production ers fields in the Zellwood, FL, area. The 1991 trials were in the southeast (Losses due to weeds committee, 1984). on the Crakes Farms and in 1992 on the Lust Farms. The This loss may be higher in Florida due to year round weed soil at both sites was a Lauderhill muck (approx 60% OM) growth and the varying soil types. with a pH of 6.8. 'Showcase' seed was planted 25 Mar. Most of the sweet corn in Florida is grown on the or 1991 and 'Ultimate' 11 Mar. 1992 on 3 foot row centers in ganic soils of the Everglades and the Zellwood areas. Her a randomized complete block design. Maintenance of plots bicides cleared for use for preemergence control of ger was done according to grower practice except no cultiva minating annuals, especially grasses are more restricted for tion was used. Seep irrigation was used in both years. organic soils than mineral soils. Herbicides were applied using a CO2 powered back Alachlor has been restricted from use in Florida due to pack sprayer calibrated to deliver 30 gpa. In the mineral confirmed ground water contamination. Alachlor along soil, a 2 nozzle boom at 20 inches between nozzles were used. In the organic soil, the nozzles were on 18 inches Florida Agricultural Experiment Station Journal Series No. N-00750. centers. Post-directed sprays were applied with a single 326 Proc. Fla. State Hort. Soc. 105: 1992. Table 3. Effects of postemergence herbicides on vigor and weed control in sweet corn in mineral soils, Gainesville, FL 1991-92. Ratings (%)z 6-10-91 Rate Applic 6-15-92 Herbicide lb/A Timing Vigor AMACH^ RAPRA Vigor AMACH CHEAL DIGSP Hoed Check 77 90 92 80 100 100 100 Weedy Check 75 0 0 78 0 0 0 Bromoxynil .375 EPOST? — — — 93 98 100 0 Bromoxynil .375 EPOST — — — 93 98 100 0 +Atrazine 1.0 Pyridate .45 EPOST 55 95 90 95 100 100 0 +Atrazine + COC 1 Pyridate .7 EPOST 77 100 100 95 98 100 0 +Atrazine + COC 1 Pyridate .9 EPOST 72 100 100 88 100 100 0 +Atrazine + COC .2 Sethoxydim .2 POST 62 0 0 85 0 0 80 +COC DIR Sethoxydim .2 POST 82 90 95 80 70 50 60 +Atrazine + COC 1 DIR Sethoxydim .2 POST 90 92 93 98 95 63 63 +Linuron + COC 1 DIR Linuron 1 POST 89 93 94 93 100 59 53 + COC DIR LSD (.05) 25 12 19 18 24 8 19 zRatings are 0 = no vigor (dead) or no control to 100 where no loss of vigor and complete control. See Table 1. y(AMACH) smooth pigweed, (RAPRA) wild radish, (CHEAL) lambsquarter, (DIGSP) crabgrass. "Application - (EPOST) early postemergence, (Post DIR) post directed. plus atrazine treatments. Good control of smooth pigweed Control of purslane was significantly lower with was obtained even though the applications were not made bromoxynil alone than with bromoxynil and pyridate + over the tops of these weeds (Table 4). atrazine at Zellwood in 1992. Sethoxydim did not control, The bromoxynil and all 3 rates of pyridate plus atrazine nor was expected to control, purslane, but atrazine + provided excellent control of both smooth pigweed and sethoxydim and linuron treatments provided excellent lambsquarter at Gainesville in 1992. The post-directed control of this weed. linuron also provided excellent control of smooth pigweed Bromoxynil, bromoxynil + atrazine and all 3 rates of but control of lambsquarter was only fair. Both weed pyridate + atrazine provided no or poor control of crab- species were sprayed along the side of the plants at the grass and barnyardgrass in 1992. post directed stage. Smooth pigweed was killed, but Crabgrass was tall and extremely thick at Gainesville in lambsquarter was only partially controlled by this applica 1992. Control of crabgrass with sethoxydim and the tion. sethoxydim tank mix was better than with linuron alone. Table 4. Effects of postemergence herbicides on vigor and weed control in sweet corn in organic soils, Gainesville, FL 1991-92. Ratings (%)z 5-30-91 5-14-92 Herbicide lb/A Timing Vigor AMACHy PANDI Vigor POROL ECHCG Weedy Check 70 0 0 100 0 0 Bromoxynil .375 EPOSTX — — — 88 73 20 Bromoxynil .375 EPOST — — — 90 95 43 +Atrazine 1.0 Pyridate .45 EPOST 75 73 78 98 98 50 +Atrazine + COC 1 Pyridate .7 EPOST — — — 88 94 50 +Atrazine + COC 1 Pyridate .9 EPOST — — — 86 94 45 +Atrazine + COC 1 Sethoxydim .2 POST 75 0 95 89 0 100 4-por Sethoxydim .2 POST 83 33 84 96 94 89 +Atrazine + COC 2 DIR Sethoxydim .2 POST 78 70 98 100 99 99 + Linuron + COC 1 DIR Linuron 1 POST 65 78 88 100 98 78 + COC DIR LSD (.05) 13 25 18 10 14 34 zRatings are 0 = no vigor (dead) or no control to 100 where no loss of vigor and complete control. See Table 1. y(AMACH) smooth pigweed, (PANDI) fall pancum, (POROL) puslane, (ECHCG) barnyardgrass. "Application - (EPOST) early postemergence, (Post DIR) post directed. Proc. Fla. State Hort. Soc. 105: 1992. 329 Reduction of control in these cases was primarily due to atrazine also increased its broadleaf activity. Application of lack of coverage and the size of the plants at treatment. At pendimethalin at the spike stage was safe and efficacious Zellwood in 1992, barnyardgrass was controlled very well, on mineral soils. On organic soils, preplant incorporation even though these grasses were very tall at the time of and preemergence applications should be tested.
Load more

Recommended publications
  • 2,4-Dichlorophenoxyacetic Acid
    2,4-Dichlorophenoxyacetic acid 2,4-Dichlorophenoxyacetic acid IUPAC (2,4-dichlorophenoxy)acetic acid name 2,4-D Other hedonal names trinoxol Identifiers CAS [94-75-7] number SMILES OC(COC1=CC=C(Cl)C=C1Cl)=O ChemSpider 1441 ID Properties Molecular C H Cl O formula 8 6 2 3 Molar mass 221.04 g mol−1 Appearance white to yellow powder Melting point 140.5 °C (413.5 K) Boiling 160 °C (0.4 mm Hg) point Solubility in 900 mg/L (25 °C) water Related compounds Related 2,4,5-T, Dichlorprop compounds Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) 2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic herbicide used in the control of broadleaf weeds. It is the most widely used herbicide in the world, and the third most commonly used in North America.[1] 2,4-D is also an important synthetic auxin, often used in laboratories for plant research and as a supplement in plant cell culture media such as MS medium. History 2,4-D was developed during World War II by a British team at Rothamsted Experimental Station, under the leadership of Judah Hirsch Quastel, aiming to increase crop yields for a nation at war.[citation needed] When it was commercially released in 1946, it became the first successful selective herbicide and allowed for greatly enhanced weed control in wheat, maize (corn), rice, and similar cereal grass crop, because it only kills dicots, leaving behind monocots. Mechanism of herbicide action 2,4-D is a synthetic auxin, which is a class of plant growth regulators.
    [Show full text]
  • Exposure to Herbicides in House Dust and Risk of Childhood Acute Lymphoblastic Leukemia
    Journal of Exposure Science and Environmental Epidemiology (2013) 23, 363–370 & 2013 Nature America, Inc. All rights reserved 1559-0631/13 www.nature.com/jes ORIGINAL ARTICLE Exposure to herbicides in house dust and risk of childhood acute lymphoblastic leukemia Catherine Metayer1, Joanne S. Colt2, Patricia A. Buffler1, Helen D. Reed3, Steve Selvin1, Vonda Crouse4 and Mary H. Ward2 We examine the association between exposure to herbicides and childhood acute lymphoblastic leukemia (ALL). Dust samples were collected from homes of 269 ALL cases and 333 healthy controls (o8 years of age at diagnosis/reference date and residing in same home since diagnosis/reference date) in California, using a high-volume surface sampler or household vacuum bags. Amounts of agricultural or professional herbicides (alachlor, metolachlor, bromoxynil, bromoxynil octanoate, pebulate, butylate, prometryn, simazine, ethalfluralin, and pendimethalin) and residential herbicides (cyanazine, trifluralin, 2-methyl-4- chlorophenoxyacetic acid (MCPA), mecoprop, 2,4-dichlorophenoxyacetic acid (2,4-D), chlorthal, and dicamba) were measured. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by logistic regression. Models included the herbicide of interest, age, sex, race/ethnicity, household income, year and season of dust sampling, neighborhood type, and residence type. The risk of childhood ALL was associated with dust levels of chlorthal; compared to homes with no detections, ORs for the first, second, and third tertiles were 1.49 (95% CI: 0.82–2.72), 1.49 (95% CI: 0.83–2.67), and 1.57 (95% CI: 0.90–2.73), respectively (P-value for linear trend ¼ 0.05). The magnitude of this association appeared to be higher in the presence of alachlor.
    [Show full text]
  • Weed Control in Direct-Seeded Field Pea Gregory J
    Weed Control in Direct-seeded Field Pea Gregory J. Endres and Blaine G. Schatz Weed control and field pea response to selected soil- and POST-applied herbicides were evaluated in a randomized complete-block design with three replicates. The experiment was conducted on a Heimdahl loam soil with 6.7 pH and 2.9% organic matter at the NDSU Carrington Research Extension Center. Herbicide treatments were applied to 5- by 25-ft plots with a pressurized hand-held plot sprayer at 17 gal/A and 30 psi through 8002 flat-fan nozzles. Fall sulfentrazone treatments were applied October 25, 2004 to a moist soil surface with 47 F, 71% RH, 15% clear sky, and 11 mph wind. On April 28, 2005, inoculated 'Integra' field pea was seeded into standing wheat stubble in 7-inch rows at a rate of 300,000 pure live seeds/A. PRE treatments were applied to a dry soil surface on April 30 with 31 F, 64% RH, 30% clear sky, and 10 mph wind. Rainfall totaled 1.22 inches 8 d following PRE application. The trial area was treated on May 6 with a PRE burn-down application of glyphosate at 0.75 lb ae/A plus ammonium sulfate at 1% v/v. The early POST (EPOST) treatment was applied on May 23 with 73 F, 35% RH, 100% cloudy sky, and 6 mph wind to 2-inch tall field pea, 1- to 2-leaf green and yellow foxtail, 0.5-inch tall common lambsquarters, 0.5-inch tall prostrate and redroot pigweed, and 0.5-inch tall wild buckwheat.
    [Show full text]
  • Appendix C - Wildlife 9/8/2008
    INVASIVE PLANT BIOLOGICAL ASSESSMENT Umatilla and Wallowa-Whitman National Forests Appendix C - Wildlife 9/8/2008 APPENDIX C - WILDLIFE C-1 INVASIVE PLANT BIOLOGICAL ASSESSMENT Umatilla and Wallowa-Whitman National Forests Appendix C - Wildlife 9/8/2008 C-2 INVASIVE PLANT BIOLOGICAL ASSESSMENT Umatilla and Wallowa-Whitman National Forests Appendix C - Wildlife 9/8/2008 Appendix C ......................................................................................................................... 1 Wildlife ............................................................................................................................... 1 Exposure Groups for Forest Service Sensitive Wildlife ................................................. 6 Effects of the Alternatives on Sensitive Wildlife ........................................................... 7 Tables C-5 – C-13 Herbicides ................................................................................... 11 Umatilla and Wallowa-Whitman National Forest Herbicide Spray Buffers ................ 12 Aquatics............................................................................................................. 15 Wildlife .............................................................................................................. 15 Worker Health: Based on backpack spray applications. ................................. 15 Public Health: ................................................................................................... 16 Summary of Herbicide Effects to Wildlife
    [Show full text]
  • INDEX to PESTICIDE TYPES and FAMILIES and PART 180 TOLERANCE INFORMATION of PESTICIDE CHEMICALS in FOOD and FEED COMMODITIES
    US Environmental Protection Agency Office of Pesticide Programs INDEX to PESTICIDE TYPES and FAMILIES and PART 180 TOLERANCE INFORMATION of PESTICIDE CHEMICALS in FOOD and FEED COMMODITIES Note: Pesticide tolerance information is updated in the Code of Federal Regulations on a weekly basis. EPA plans to update these indexes biannually. These indexes are current as of the date indicated in the pdf file. For the latest information on pesticide tolerances, please check the electronic Code of Federal Regulations (eCFR) at http://www.access.gpo.gov/nara/cfr/waisidx_07/40cfrv23_07.html 1 40 CFR Type Family Common name CAS Number PC code 180.163 Acaricide bridged diphenyl Dicofol (1,1-Bis(chlorophenyl)-2,2,2-trichloroethanol) 115-32-2 10501 180.198 Acaricide phosphonate Trichlorfon 52-68-6 57901 180.259 Acaricide sulfite ester Propargite 2312-35-8 97601 180.446 Acaricide tetrazine Clofentezine 74115-24-5 125501 180.448 Acaricide thiazolidine Hexythiazox 78587-05-0 128849 180.517 Acaricide phenylpyrazole Fipronil 120068-37-3 129121 180.566 Acaricide pyrazole Fenpyroximate 134098-61-6 129131 180.572 Acaricide carbazate Bifenazate 149877-41-8 586 180.593 Acaricide unclassified Etoxazole 153233-91-1 107091 180.599 Acaricide unclassified Acequinocyl 57960-19-7 6329 180.341 Acaricide, fungicide dinitrophenol Dinocap (2, 4-Dinitro-6-octylphenyl crotonate and 2,6-dinitro-4- 39300-45-3 36001 octylphenyl crotonate} 180.111 Acaricide, insecticide organophosphorus Malathion 121-75-5 57701 180.182 Acaricide, insecticide cyclodiene Endosulfan 115-29-7 79401
    [Show full text]
  • Weed Management—Major Crops
    Weed Technology 2010 24:1–5 Weed Management—Major Crops Annual Grass Control in Strip-Tillage Peanut Production with Delayed Applications of Pendimethalin W. Carroll Johnson, III, Eric P. Prostko, and Benjamin G. Mullinix, Jr.* In strip-tillage peanut production, situations occur when dinitroaniline herbicides are not applied in a timely manner. In these cases, dinitroaniline herbicides would be applied days or weeks after seeding. However, there is no information that documents the effects of delayed applications on weed control. Trials were conducted in 2004, 2005, and 2007 in Georgia to determine the weed control efficacy of delayed applications of pendimethalin in strip-tillage peanut production. Treatments included seven timings of pendimethalin application and three pendimethalin-containing herbicide combinations. Timings of application were immediately after seeding (PRE), vegetative emergence of peanut (VE), 1 wk after VE (VE+1wk), VE+2wk, VE+3wk, VE+4wk, and a nontreated control. Pendimethalin containing herbicide programs included pendimethalin plus paraquat, pendimethalin plus imazapic, and pendimethalin alone. Among the possible treatment combinations was a current producer standard timing for nonpendimethalin weed control programs in peanut, which was either imazapic or paraquat alone applied VE+3wk. Pendimethalin alone did not effectively control Texas millet regardless of time of application (69 to 77%), whereas southern crabgrass was controlled by pendimethalin alone PRE (87%). Delayed applications of pendimethalin controlled Texas millet and southern crabgrass when combined with either paraquat or imazapic, with imazapic being the preferred combination due to better efficacy on southern crabgrass than paraquat at most delayed applications. Peanut yield was improved when any of the herbicide combinations were applied PRE compared to later applications.
    [Show full text]
  • New Herbicides for Weeds in Seedling Alfalfa
    NEW HERBICIDES FOR WEEDS IN SEEDLING ALFALFA 1 Harold M. Kempen and Joe Voth Abstract: Research suggests that "better mousetraps" for control of seedling weeds in seedling alfalfa are awaiting EPA & CDFA registrations. .Buctril in combination with Poast has been effective in Kern County tests. Until registered, Butyrac in combination with Poast, seems a good option: Pursuit appears to offer the best program because it controls chickweed along with most winter weeds and may suppress yellow nutsedge and johnsongrass. Keywords: Seedling alfalfa, herbicides, grass weeds, broadleaf weeds. INTRODUCTION Poast was recently registered for use in alfalfa. Perhaps that is an omen that something else ~/il1 be registered in the near future as well. It is still possibl~! When I accepted this speaking engagement, I had high hopes that Buctril would be registered by this summer. But that date has passed and the prognosis for labelling of it by next spring is poor. Yes, it is registered in the United States of America, but it isn't registered in sovereign California. This report will focus on three promising treatments: 1. Buctril ME-4 + Poast, Fusilade 2000 or Select; 2. Butyrac Amine + Poast, Fusilade or Select; 3. Pursuit. HERBICIDES MENTIONED IN THIS REPORT Buctril bromoxynil Brominal bromoxynil Butyrac 2,4-DB Butoxone 2,4-DB Poast sethoxydim Fusilade 2000 fluazifop-P-butyl Assure quizalofop Select clethodim Whip fenoxyprop-ethyl Verdict haloxyfop Pursuit imazethapyr Gramoxone Super paraquat BUCTRIL + SELECTIVE GRASS HERBICIDES In Kern County, where we grow almost 90,000 acres and are 4th in alfalfa marketincr in California, we have studied bromoxynil for several years, alone and in combination with the selective grass herbicides: Poast, Fusilade, Assure, Select and Verdict.
    [Show full text]
  • Corn Herbicides to Control Glyphsoate-Resistant Canola Volunteers
    AGRONOMY SCIENCES RESEARCHRESEARCH UPDAUPDATETE Corn Herbicides to Control Glyphosate-Resistant Canola Volunteers 2013 Background Table 1. Herbicide treatments. • With the rapid adoption of glyphosate-resistant corn in Western Treatment Application Rate/Acre Canada, glyphosate-resistant canola volunteers have become a major weed concern to corn producers in the region. 1 Gly Only (Check) 1 L/acre (360g ae) • The Pest Management Regulatory Agency now allows 2 Gly + Dicamba 1 L/acre + 0.243 L/acre herbicides to be tank-mixed if they have individual registrations 3 Gly + 2,4-D 1 L/acre + 0.4 L/acre (600g/L) on the crop and have a common application timing. 4 Gly + MCPA Amine 1 L/acre + 0.45L/acre • Several herbicide options are available to control glyphosate 5 Gly + Bromoxynil 1 L/acre + 0.48 L/acre tolerant canola volunteers in corn; however, some herbicides may have undesirable effects on corn. Gly / Bromoxynil 6 1 L/acre + 0.48 L/acre (Split Application*) Objectives * Glyphosate and bromoxynil applied separately at V3 stage. • Assess crop injury and yield effects of various herbicides tank- mixed with glyphosate to control glyphosate-resistant canola • Herbicide injury scores were recorded at: volunteers in glyphosate-resistant corn. • 3-5 days after treatment • 7-10 days after treatment • Identify the most suitable post-emergence strategy for • 21-24 days after treatment managing glyphosate-resistant canola volunteers in glyphosate-resistant corn. • Other recorded observations include: • Brittle snap counts Study Description • Yield (bu/acre) & moisture (%) • Test weight (lbs/bu) • The study compared the crop response of four industry leading hybrids (Pioneer® brand and competitive) with five different Results herbicide treatments (Table 1).
    [Show full text]
  • Multiple Resistance to Glyphosate, Paraquat and Accase
    Research Article Received: 5 September 2017 Revised: 16 October 2017 Accepted article published: 26 October 2017 Published online in Wiley Online Library: 8 December 2017 (wileyonlinelibrary.com) DOI 10.1002/ps.4774 Multiple resistance to glyphosate, paraquat and ACCase-inhibiting herbicides in Italian ryegrass populations from California: confirmation and mechanisms of resistance Parsa Tehranchian,a* Vijay Nandula,b Mithila Jugulam,c Karthik Puttac and Marie Jasieniuka Abstract BACKGROUND: Glyphosate, paraquat and acetyl CoA carboxylase (ACCase)-inhibiting herbicides are widely used in California annual and perennial cropping systems. Recently, glyphosate, paraquat, and ACCase- and acetolactate synthase (ALS)-inhibitor resistance was confirmed in several Italian ryegrass populations from the Central Valley of California. This research characterized the possible mechanisms of resistance. RESULTS: Multiple-resistant populations (MR1, MR2) are resistant to several herbicides from at least three modes of action. Dose–response experiments revealed that the MR1 population was 45.9-, 122.7- and 20.5-fold, and the MR2 population was 24.8-, 93.9- and 4.0-fold less susceptible to glyphosate, sethoxydim and paraquat, respectively, than the susceptible (Sus) population. Accumulation of shikimate in Sus plants was significantly greater than in MR plants 32 h after light pretreatments. Glyphosate resistance in MR plants was at least partially due to Pro106-to-Ala and Pro106-to-Thr substitutions at site 106 of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). EPSPS gene copy number and expression level were similar in plants from the Sus and MR populations. An Ile1781-to-Leu substitution in ACCase gene of MR plants conferred a high level of resistance to sethoxydim and cross-resistance to other ACCase-inhibitors.
    [Show full text]
  • AP-42, CH 9.2.2: Pesticide Application
    9.2.2PesticideApplication 9.2.2.1General1-2 Pesticidesaresubstancesormixturesusedtocontrolplantandanimallifeforthepurposesof increasingandimprovingagriculturalproduction,protectingpublichealthfrompest-bornediseaseand discomfort,reducingpropertydamagecausedbypests,andimprovingtheaestheticqualityofoutdoor orindoorsurroundings.Pesticidesareusedwidelyinagriculture,byhomeowners,byindustry,andby governmentagencies.Thelargestusageofchemicalswithpesticidalactivity,byweightof"active ingredient"(AI),isinagriculture.Agriculturalpesticidesareusedforcost-effectivecontrolofweeds, insects,mites,fungi,nematodes,andotherthreatstotheyield,quality,orsafetyoffood.Theannual U.S.usageofpesticideAIs(i.e.,insecticides,herbicides,andfungicides)isover800millionpounds. AiremissionsfrompesticideusearisebecauseofthevolatilenatureofmanyAIs,solvents, andotheradditivesusedinformulations,andofthedustynatureofsomeformulations.Mostmodern pesticidesareorganiccompounds.EmissionscanresultdirectlyduringapplicationorastheAIor solventvolatilizesovertimefromsoilandvegetation.Thisdiscussionwillfocusonemissionfactors forvolatilization.Thereareinsufficientdataavailableonparticulateemissionstopermitemission factordevelopment. 9.2.2.2ProcessDescription3-6 ApplicationMethods- Pesticideapplicationmethodsvaryaccordingtothetargetpestandtothecroporothervalue tobeprotected.Insomecases,thepesticideisapplieddirectlytothepest,andinotherstothehost plant.Instillothers,itisusedonthesoilorinanenclosedairspace.Pesticidemanufacturershave developedvariousformulationsofAIstomeetboththepestcontrolneedsandthepreferred
    [Show full text]
  • Weed Control Guide for Ohio, Indiana and Illinois
    Pub# WS16 / Bulletin 789 / IL15 OHIO STATE UNIVERSITY EXTENSION Tables Table 1. Weed Response to “Burndown” Herbicides .............................................................................................19 Table 2. Application Intervals for Early Preplant Herbicides ............................................................................... 20 Table 3. Weed Response to Preplant/Preemergence Herbicides in Corn—Grasses ....................................30 WEED Table 4. Weed Response to Preplant/Preemergence Herbicides in Corn—Broadleaf Weeds ....................31 Table 5. Weed Response to Postemergence Herbicides in Corn—Grasses ...................................................32 Table 6. Weed Response to Postemergence Herbicides in Corn—Broadleaf Weeds ..................................33 2015 CONTROL Table 7. Grazing and Forage (Silage, Hay, etc.) Intervals for Herbicide-Treated Corn ................................. 66 OHIO, INDIANA Table 8. Rainfast Intervals, Spray Additives, and Maximum Crop Size for Postemergence Corn Herbicides .........................................................................................................................................................68 AND ILLINOIS Table 9. Herbicides Labeled for Use on Field Corn, Seed Corn, Popcorn, and Sweet Corn ..................... 69 GUIDE Table 10. Herbicide and Soil Insecticide Use Precautions ......................................................................................71 Table 11. Weed Response to Herbicides in Popcorn and Sweet Corn—Grasses
    [Show full text]
  • Use of Mesotrione for Annual Bluegrass (Poa Annua L.) at Cool
    USE OF MESOTRIONE FOR ANNUAL BLUEGRASS (POA ANNUA L.) AT COOL- SEASON TURFGRASS ESTABLISHMENT by KATELYN A. VENNER A Thesis submitted to the Graduate School-New Brunswick Rutgers, The State University of New Jersey in partial fulfillment of the requirements for the degree of Master of Science Graduate Program in Plant Biology written under the direction of Stephen E. Hart Ph.D. and approved by ________________________ ________________________ ________________________ New Brunswick, New Jersey October, 2011 ABSTRACT OF THE THESIS USE OF MESOTRIONE AT COOL-SEASON TURFGRASS ESTABLISMENT By Katelyn Anne Venner Thesis director: Stephen E. Hart Annual bluegrass is a problematic weed in highly maintained turfgrass environments, and is difficult to control due to its adaptability to highly maintained turfgrass environments and lack of highly effective chemical control options. Mesotrione is a relatively new herbicide which has been found to show some level of control of annual bluegrass, and is safe to use at cool season turfgrass establishment. Thus, mesotrione has potential to be utilized for weed control in cultivated sod production. The objectives of this research were to evaluate mesotrione to determine: 1) tolerance of selected tall fescue cultivars, an important turfgrass species cultivated for sod, to applications of mesotrione; 2) the length of residual of mesotrione versus prodiamine, bensulide and dithiopyr for control of annual bluegrass; and 3) potential of mesotrione to control winter annual broadleaf weeds at Kentucky bluegrass establishment. Tall fescue cultivars were found to be tolerant to mesotrione applications made preemergence and preemergence plus 4 weeks after emergence at higher rates than required for weed control.
    [Show full text]