Influence of Time of Day on Dicamba and Glyphosate Efficacy

2021 ◽  
pp. 1-20
Author(s):  
Jacob R. Kalina ◽  
Chris B. Corkern ◽  
Donn G. Shilling ◽  
Nicholas T. Basinger ◽  
Timothy L. Grey
Keyword(s):  
Weed Control ◽  
Time Of Day ◽  
Genetically Engineered ◽  
Herbicide Application ◽  
Weed Species ◽  
Application Timing ◽  
Group 4 ◽  
Crop Varieties ◽  
Prickly Sida ◽  
Multiple Field

Abstract Renewed interest in studying auxin herbicides (WSSA group 4) is increasing due to the release of genetically engineered crop varieties that are tolerant to PRE and POST applications of specific formulations of dicamba. The development of auxin-resistant crops was in response to the development of herbicide-resistant weed species to glyphosate and other herbicides. Research was conducted at multiple field locations in Georgia in 2018 and 2019 to examine weed control when POST herbicides were applied to dicamba and glyphosate-resistant cotton at eight different points in time over a 24-hr period. Applications occurred at 1-hr prior to sunrise all the way up to midnight in one day to examine the effect of herbicide application timing on broadleaf weed control. Glyphosate, dicamba, and glyphosate plus dicamba were applied at each timing. Visual ratings of weed control were evaluated at 7, 14, 21, and 28 days after treatment (DAT). Weed control was affected by herbicide application timing. Midnight applications resulted in the lowest levels of control. Sicklepod, pitted morningglory, and prickly sida control was 49, 38, and 41% respectively. Greatest control of all three species (up to 99%) occurred from the noon to 1-hr prior to sunset application timings. Orthogonal contrasts of timing of application indicated that weed control was improved with day > night and pre-dawn > midnight.

Influence of Simulated Rainfall and Soil Moisture on Herbicidal Activity of Cinmethylin

Weed Science ◽  
1990 ◽  
Vol 38 (3) ◽  
pp. 267-272 ◽  
Author(s):  
Steven G. Russell ◽  
Thomas J. Monaco ◽  
Jerome B. Weber
Keyword(s):  
Weed Control ◽  
Sandy Loam ◽  
Field Trials ◽  
Herbicidal Activity ◽  
Herbicide Application ◽  
Weed Species ◽  
Green Foxtail ◽  
Loam Soil ◽  
Dry Soil ◽  
Prickly Sida

Field trials were conducted in 1986 and 1987 to determine the effects of moisture on herbicidal activity of cinmethylin applied preemergence at 0.0, 0.3, 0.6, and 0.9 kg ai ha to both dry and moist sandy loam soil. Herbicide application was followed by varying amounts of irrigation. Weed species included velvetleaf, prickly sida, green foxtail, and barnyardgrass. When cinmethylin was applied to a moist soil or when 2.5 cm of irrigation was applied 5 days after cinmethylin application to a dry soil, overall weed control was reduced. Optimum weed control resulted from cinmethylin application to dry soil followed either by a 2.5-cm irrigation within 8 h or a 7.6-cm irrigation within 36 h.

Time of Day Impacts Postemergence Weed Control in Corn

2009 ◽  
Vol 23 (3) ◽  
pp. 346-355 ◽  
Author(s):  
Christie L. Stewart ◽  
Robert E. Nurse ◽  
Peter H. Sikkema
Keyword(s):  
Light Intensity ◽  
Weed Control ◽  
Air Temperature ◽  
Ambient Air ◽  
Field Trials ◽  
Time Of Day ◽  
Weed Species ◽  
Application Timing ◽  
Reducing Costs ◽  
Species Specific

Field trials were conducted from 2005 to 2007 at two locations in southwestern Ontario to investigate how weed control in corn was affected by the time of day that herbicides were applied. Weed control following the application of six POST herbicides (atrazine, bromoxynil, dicamba/diflufenzopyr, glyphosate, glufosinate, and nicosulfuron) at 06:00, 09:00, 12:00, 15:00, 18:00, 21:00, and 24:00 h was assessed. For many weed species herbicide efficacy was reduced when applications were made at 06:00, 21:00, and 24:00 h. Velvetleaf was the most sensitive to the time of day effect, followed by common ragweed, common lambsquarters, and redroot pigweed. Annual grasses were not as sensitive to application timing; however, control of barnyardgrass and green foxtail was reduced in some environments at 06:00 h and after 21:00 h. Only in the most severe cases was the grain yield of corn reduced due to decreased weed control. Daily changes in air temperature, relative humidity, and light intensity that cause species-specific physiological changes may account for the variation in weed control throughout the day. The results of this research suggest that there is a strong species-specific influence of ambient air temperature, light intensity, and leaf orientation on the efficacy of POST herbicides. These results should aid growers in applying herbicides when they are most efficacious, thus reducing costs associated with reduced efficacy.

Weed Control in Glyphosate-Resistant Corn as Affected by Preemergence Herbicide and Timing of Postemergence Herbicide Application

2006 ◽  
Vol 20 (3) ◽  
pp. 564-570 ◽  
Author(s):  
Robert G. Parker ◽  
Alan C. York ◽  
David L. Jordan
Keyword(s):  
Grain Yield ◽  
Weed Control ◽  
Field Studies ◽  
Herbicide Application ◽  
Application Timing ◽  
Common Lambsquarters ◽  
Herbicide Treatments ◽  
Prickly Sida ◽  
Smooth Pigweed ◽  
Or Applications

Field studies were conducted at three locations during both 2002 and 2003 to evaluate weed control and response of glyphosate-resistant (GR) corn to glyphosate or nicosulfuron plus atrazine applied POST at three application timings with and without alachlor plus atrazine applied PRE. The POST herbicides were applied timely (5- to 9-cm weeds) or applications were delayed 1 or 2 wk. All treatments, except the weedy check, were followed by glyphosate postemergence-directed (PDIR) 4 wk after the timely POST application. Common lambsquarters, common ragweed, Palmer amaranth, prickly sida, and smooth pigweed were controlled at least 94% regardless of PRE or POST treatments. Large crabgrass and fall panicum were controlled at least 96% by glyphosate regardless of PRE herbicide or POST application timing. In contrast, control by nicosulfuron plus atrazine POST in the absence of PRE herbicide decreased as application was delayed. Sicklepod was controlled at least 94% when POST herbicides were applied timely, but control by both POST herbicide treatments decreased with delayed application regardless of PRE herbicide. Tall morningglory was controlled 93% or greater by POST herbicides applied timely. Control by both POST herbicide treatments decreased as application was delayed, with glyphosate being affected more by timing than nicosulfuron plus atrazine. Corn grain yield was similar with glyphosate and nicosulfuron plus atrazine. Yield was unaffected by POST application timing when PRE herbicides were included. Without PRE herbicide, grain yield decreased as POST herbicide application was delayed.

Influence of Herbicide Application Rate, Timing, and Interrow Cultivation on Weed Control and Corn (Zea mays) Yield in Glufosinate-Resistant and Glyphosate-Resistant Corn

1999 ◽  
Vol 13 (4) ◽  
pp. 807-813 ◽  
Author(s):  
Brent E. Tharp ◽  
James J. Kells
Keyword(s):  
Zea Mays ◽  
Weed Control ◽  
Field Trials ◽  
Application Rate ◽  
Corn Yield ◽  
Herbicide Application ◽  
Weed Species ◽  
Application Timing ◽  
Glufosinate Ammonium ◽  
Application Rates

Field trials were conducted in 1996 and 1997 to determine the influence of glufosinate and glyphosate application rates, application timings, and interrow cultivation on weed control and corn yield. Glufosinate-ammonium rates ranged from 0.18 to 0.41 kg ai/ha, while rates for the isopropylamine salt of glyphosate ranged from 0.21 to 0.84 kg ae/ha. Increasing rates of glufosinate and glyphosate often improved weed control. Control of many of the weed species was improved by delaying herbicide application timing. Weed control was most consistent from late postemergence (LPOST) applications of glufosinate at 0.41 kg ai/ha or glyphosate at 0.84 kg ae/ha. Corn yields were reduced due to incomplete weed control when the lowest rate of glufosinate was applied. Weed control from early postemergence (EPOST) glufosinate and glyphosate applications followed by cultivation was similar to weed control from LPOST glufosinate and glyphosate applications without cultivation. Interrow cultivation following glufosinate or glyphosate application did not affect corn yield.

scholarly journals FLUAZIFOP-P-BUTYL EFFICACY AS A FUNCTION OF APPLICATION TIME AND HERBICIDE DOSE

2017 ◽  
Vol 35 (0) ◽  
Author(s):  
L.F. CIESLIK ◽  
R.A. VIDAL ◽  
A.B. MACHADO ◽  
M.M. TREZZI
Keyword(s):  
Relative Humidity ◽  
Common Bean ◽  
Weed Control ◽  
Air Temperature ◽  
Field Experiments ◽  
Time Of Day ◽  
Leaf Angle ◽  
Herbicide Application ◽  
The Common ◽  
Bean Crop

ABSTRACT Grass weeds are common in summer crops and strongly decreases the grain yield of the common bean crop. The time of herbicide application influences the variability of environmental conditions and affects the product performance. The objectives of this work were to identify the time of fluazifop-p-butyl (fluazifop) application which gives best grass weed control in the common bean crop and to elucidate the environmental variables most important for the efficacy of this herbicide. Field experiments were conducted involving five application times (2 a.m., 6 a.m., 11 a.m., 4 p.m. and 9 p.m.) and five doses of fluazifop (80, 110, 140, 170 and 200 g ha-1), with additional no-herbicide control. At the time of the herbicide application it was determined the air temperature, relative humidity, the photosynthetically active radiation (PAR) and the leaf angle, whereas the weed control and the dry mass of the weed Urochloa plantaginea was assessed at 20 days after treatment (DAT). Efficacy on grass control with fluazifop was dependent on the herbicide dose and on the time of day that the product was applied. Spray at early morning hours (6 a.m.) showed better efficacy on weed control in relation to periods during warmer conditions of the day (11 a.m. and 4 p.m.). Nocturnal fluazifop application had better weed control when compared to herbicide sprayed in the afternoon. The air temperature, relative humidity and PAR were correlated to weed leaf angle, which correlated the most with fluazifop performance.

Alternatives to Atrazine for Weed Management in Processing Sweet Corn

Weed Science ◽  
2016 ◽  
Vol 64 (3) ◽  
pp. 531-539 ◽  
Author(s):  
Zubeyde Filiz Arslan ◽  
Martin M. Williams ◽  
Roger Becker ◽  
Vincent A. Fritz ◽  
R. Ed Peachey ◽  
...  
Keyword(s):  
Weed Control ◽  
Weed Management ◽  
Sweet Corn ◽  
Crop Yields ◽  
Production Systems ◽  
Field Trials ◽  
Management Systems ◽  
Weed Species ◽  
Application Timing ◽  
Production Areas

Atrazine has been the most widely used herbicide in North American processing sweet corn for decades; however, increased restrictions in recent years have reduced or eliminated atrazine use in certain production areas. The objective of this study was to identify the best stakeholder-derived weed management alternatives to atrazine in processing sweet corn. In field trials throughout the major production areas of processing sweet corn, including three states over 4 yr, 12 atrazine-free weed management treatments were compared to three standard atrazine-containing treatments and a weed-free check. Treatments varied with respect to herbicide mode of action, herbicide application timing, and interrow cultivation. All treatments included a PRE application of dimethenamid. No single weed species occurred across all sites; however, weeds observed in two or more sites included common lambsquarters, giant ragweed, morningglory species, velvetleaf, and wild-proso millet. Standard treatments containing both atrazine and mesotrione POST provided the most efficacious weed control among treatments and resulted in crop yields comparable to the weed-free check, thus demonstrating the value of atrazine in sweet corn production systems. Timely interrow cultivation in atrazine-free treatments did not consistently improve weed control. Only two atrazine-free treatments consistently resulted in weed control and crop yield comparable to standard treatments with atrazine POST: treatments with tembotrione POST either with or without interrow cultivation. Additional atrazine-free treatments with topramezone applied POST worked well in Oregon where small-seeded weed species were prevalent. This work demonstrates that certain atrazine-free weed management systems, based on input from the sweet corn growers and processors who would adopt this technology, are comparable in performance to standard atrazine-containing weed management systems.

Weed Control for Close-Drilled Soybeans

Weed Science ◽  
1972 ◽  
Vol 20 (1) ◽  
pp. 16-19 ◽  
Author(s):  
L. M. Wax
Keyword(s):  
Glycine Max ◽  
Weed Control ◽  
Yield Reduction ◽  
Herbicide Application ◽  
Weed Species ◽  
Soybean Yield ◽  
Planting Time ◽  
Large Numbers ◽  
Seedbed Preparation

Delayed planting or “stale seedbed” for weed control in close-drilled (20-cm rows) soybeans [Glycine max(L.) Merr. ‘Amsoy’] was evaluated for 3 years. The system combined final seedbed preparation 3 to 6 weeks before planting with herbicide application at planting time. The best control of six weed species and highest soybean yields were obtained bya,a,a-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) application at the time of seedbed preparation followed by 3-(3,4-dichlorophenyl)-1-methylurea (linuron) application at planting and by linuron application at planting without the early trifluralin application. Applications of 1,1′-dimethyl-4,4′-bipyridinium ion (paraquat) at planting, either with or without trifluralin treatments, resulted in less weed control and lower soybean yields than comparable treatments with linuron. However, even the best treatments failed to provide the weed control necessary to prevent substantial soybean yield reduction in heavy infestations of weeds that emerge in large numbers after planting, and that resist the phytotoxic action of the herbicides.

The influence of soybean population and POST herbicide application timing on in-season and subsequent-season Palmer amaranth (Amaranthus palmeri) control and economic returns

2020 ◽  
pp. 1-7
Author(s):  
Denis J. Mahoney ◽  
David L. Jordan ◽  
Andrew T. Hare ◽  
Nilda Roma-Burgos ◽  
Katherine M. Jennings ◽  
...  
Keyword(s):  
Weed Control ◽  
High Density ◽  
Palmer Amaranth ◽  
Economic Returns ◽  
Herbicide Application ◽  
Application Timing ◽  
Herbicide Resistant ◽  
Resistance Evolution ◽  
Subsequent Crop ◽  
Density Population

Abstract Overreliance on herbicides for weed control has led to the evolution of herbicide-resistant Palmer amaranth populations. Farm managers should consider the long-term consequences of their short-term management decisions, especially when considering the soil weed seedbank. The objectives of this research were to (1) determine how soybean population and POST herbicide application timing affects in-season Palmer amaranth control and soybean yield, and (2) how those variables influence Palmer amaranth densities and cotton yields the following season. Soybeans were planted (19-cm row spacing) at a low-, medium-, and high-density population (268,000, 546,000, and 778,000 plants ha–1, respectively). Fomesafen and clethodim (280 and 210 g ai ha–1, respectively) were applied at the VE, V1, or V2 to V3 soybean growth stage. Nontreated plots were also included to assess the effect of soybean population alone. The following season, cotton was planted into these plots so as to understand the effects of soybean planting population on Palmer amaranth densities in the subsequent crop. When an herbicide application occurred at the V1 or V2 to V3 soybean stage, weed control in the high-density soybean population increased 17% to 23% compared to the low-density population. Economic return was not influenced by soybean population and was increased 72% to 94% with herbicide application compared to no treatment. In the subsequent cotton crop, Palmer amaranth densities were 24% to 39% lower 3 wk after planting when following soybean sprayed with herbicides compared to soybean without herbicides. Additionally, Palmer amaranth densities in cotton were 19% lower when soybean was treated at the VE stage compared to later stages. Thus, increasing soybean population can improve Palmer amaranth control without adversely affecting economic returns and can reduce future weed densities. Reducing the weed seedbank and selection pressure from herbicides are critical in mitigating resistance evolution.

Weed management with CGA-362622 in transgenic and nontransgenic cotton

Weed Science ◽  
2003 ◽  
Vol 51 (6) ◽  
pp. 1002-1009 ◽  
Author(s):  
Dunk Porterfield ◽  
John W. Wilcut ◽  
Jerry W. Wells ◽  
Scott B. Clewis
Keyword(s):  
North Carolina ◽  
Weed Control ◽  
Weed Management ◽  
Field Studies ◽  
Palmer Amaranth ◽  
Management Systems ◽  
Weed Species ◽  
Crop Tolerance ◽  
Prickly Sida ◽  
Smooth Pigweed

Field studies conducted at three locations in North Carolina in 1998 and 1999 evaluated crop tolerance, weed control, and yield with CGA-362622 alone and in combination with various weed management systems in transgenic and nontransgenic cotton systems. The herbicide systems used bromoxynil, CGA-362622, glyphosate, and pyrithiobac applied alone early postemergence (EPOST) or mixtures of CGA-362622 plus bromoxynil, glyphosate, or pyrithiobac applied EPOST. Trifluralin preplant incorporated followed by (fb) fluometuron preemergence (PRE) alone or fb a late POST–directed (LAYBY) treatment of prometryn plus MSMA controlled all the weed species present less than 90%. Herbicide systems that included soil-applied and LAYBY herbicides plus glyphosate EPOST or mixtures of CGA-362622 EPOST plus bromoxynil, glyphosate, or pyrithiobac controlled broadleaf signalgrass, entireleaf morningglory, large crabgrass, Palmer amaranth, prickly sida, sicklepod, and smooth pigweed at least 90%. Only cotton treated with these herbicide systems yielded equivalent to the weed-free check for each cultivar. Bromoxynil systems did not control Palmer amaranth and sicklepod, pyrithiobac systems did not control sicklepod, and CGA-362622 systems did not control prickly sida.

Utility of Clomazone for Annual Grass and Broadleaf Weed Control in Peanut (Arachis hypogaea)

1994 ◽  
Vol 8 (1) ◽  
pp. 23-27 ◽  
Author(s):  
David L. Jordan ◽  
John W. Wilcut ◽  
Leslie D. Fortner
Keyword(s):  
Weed Control ◽  
Arachis Hypogaea ◽  
Field Experiments ◽  
Systems Approach ◽  
Annual Grass ◽  
Weed Species ◽  
Common Ragweed ◽  
Prickly Sida ◽  
Better Than ◽  
Large Crabgrass

Field experiments conducted in 1988 and 1989 evaluated clomazone alone and in a systems approach for weed control in peanut. Clomazone PPI at 0.8 kg ai/ha controlled common ragweed, prickly sida, spurred anoda, and tropic croton better than ethalfluralin and/or metolachlor applied PPI. POST application of acifluorfen plus bentazon was not needed to control these weeds when clomazone was used. Acifluorfen plus bentazon improved control of these weeds when clomazone was not used and generally were necessary to obtain peanut yields regardless of the soil-applied herbicides. Alachlor PRE did not improve clomazone control of any weed species evaluated. Fall panicum and large crabgrass control was similar with clomazone or clomazone plus ethalfluralin.

Sign in / Sign up

Export Citation Format

Share Document