scholarly journals Junglerice (Echinochloa colona) Control with Sequential Applications of Glyphosate and Clethodim to Dicamba

2021 ◽  
pp. 1-18
Author(s):  
Clay M. Perkins ◽  
Thomas C. Mueller ◽  
Lawrence E. Steckel

Abstract Junglerice is becoming more prevalent in Tennessee, Arkansas and Mississippi row crop fields. The evolution of glyphosate-resistant junglerice populations is one reason for the increase. Another possible explanation is that glyphosate and clethodim grass activity is being antagonized by dicamba. This question has led to research to examine if sequential applications alleviate antagonism observed with dicamba plus glyphosate and/or clethodim mixtures and determine if 24 h, 72 h or 168 h sequential treatments of those herbicides can improve junglerice control. Glyphosate + clethodim applications provided >90% junglerice control. The observed levels of antagonism varied by whether the location of the test was in the greenhouse or the field and the timing of applications. In the greenhouse, clethodim + dicamba provided excellent control while in the field the same treatment showed over a 30% reduction in junglerice control compared with clethodim alone. However, control was restored by using a mixture of glyphosate + clethodim without dicamba. The environment at the time of application and relative glyphosate-resistance (GR) level of the junglerice influenced the overall control of these sequential applications. Clethodim applied first followed by dicamba at 72 or 168 h, better control was observed compared with applying dicamba followed by clethodim. Overall, mixing glyphosate + clethodim provided the most complete junglerice control regardless of timing. These data confirm that leaving dicamba out of the spray tank will mitigate herbicide antagonism on junglerice control. These data would also indicate that avoiding dicamba and glyphosate mixtures will also improve the consistency of control with glyphosate-susceptible junglerice.

2015 ◽  
Vol 29 (1) ◽  
pp. 108-114 ◽  
Author(s):  
Glenn Wehtje ◽  
Q. Yang ◽  
Charles H. Gilliam ◽  
Anna-Marie Murphy ◽  
Jason Fausey

Flumioxazin is commonly used in nursery production for PRE weed control. Container nursery producers are of the opinion that the granular formulation is less effective than the sprayable formulation. Under the hypothesis that the granular formulation may require more water for activation, an experiment was conducted to evaluate the interaction of flumioxazin formulation, rate, and activation moisture for PRE control of spotted spurge in a pine-bark substrate. Experiment consisted of a factorial arrangement of four experimental variables; flumioxazin formulation (granular and spray), and flumioxazin rate (0.28 and 0.42 kg ai ha−1), substrate moisture level at the time of application (dry, medium, and wet), and after-application irrigation level (a single irrigation at 0.6, 1.3, 2.5, and 5.1 cm). Treated pots were seeded with spotted spurge 2 d after the herbicide application, which was 1 d after the first irrigation. Control as indicated by spotted spurge counts and fresh weight was influenced only by flumioxazin rate and formulation. The sprayable formulation provided excellent control regardless of rate. Granular formulation was generally less effective, and additional activation moisture did not improve efficacy. Further studies were conducted with the granular formulation to determine the maximum separation distance between the spotted spurge seed and herbicide prills at which control is possible. Individual prills and spotted spurge seeds were placed on media surface at progressively increasing separation distances. Nonlinear regression of seedling survival data revealed that ≥99% control required a prill–seed separation of ≤5.2 mm. This prill–seed separation requirement is only marginally obtained with the current registered rate, i.e., 0.42 kg ai ha−1 or 168 kg product ha−1. The relationship between control and prill–seed separation distance cannot be manipulated by additional activation moisture. Inadequate contact between the spotted spurge seeds and the flumoioxazin-containing prills is likely the sole cause of inadequate control.


Land ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 735
Author(s):  
Nicholas Glass ◽  
Brenda Molano-Flores ◽  
Eduardo Dias de Oliveira ◽  
Erika Meraz ◽  
Samira Umar ◽  
...  

Restoration can recover degraded ecosystems and ecosystem services. However, effects of restoration on soil nutrient accrual are difficult to predict, partly because prior land use affects rates of soil nutrient recovery. In tallgrass prairie restorations, land-use legacy effects have not yet been quantified. We investigated topsoil carbon and nitrogen accrual within seven land-use histories: (1) row crop agriculture, (2) pasture, (3) pasture converted from row crops, (4) prairie restored from row crop, (5) prairie restored from old pasture, (6) bison prairie restored from pasture and row crops, and (7) remnant prairie. Soil samples were collected in 2008 and again in 2018 at Midewin National Tallgrass Prairie in Will County, IL. Soil samples were analyzed for bulk density, root chemistry, macro- and micronutrients, and carbon. Restored prairies contained similar soil bulk densities and rates of topsoil carbon accrual compared to each other in 2018. However, restorations from row cropping accrued nitrogen more slowly than restorations from pastures. Additionally, pastures converted from crop fields exhibited fewer legacy effects than restorations converted from crop fields. This research illustrates land-use legacy effects on soil and nutrients during grassland restorations, with implications for potential restoration trajectories and their role in carbon sequestration and ecosystem functioning.


Weed Science ◽  
1972 ◽  
Vol 20 (2) ◽  
pp. 140-142 ◽  
Author(s):  
Elroy J. Peters ◽  
S. A. Lowance

When almost no broadleaf weeds were present, 0.56 kg/ha of the butoxyethanol ester and 0.84 kg/ha of the dimethylamine salt of 4-(2,4-dichlorophenoxy)butyric acid (2, 4-DB) caused no yield reductions of seedling alfalfa (Medicago sativa L.); but 0.56 kg/ha of 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) caused slight reductions. Rates of bromoxynil above 0.56 kg/ha caused significant yield reductions of alfalfa. Broadleaf weeds, when present, shielded alfalfa from the bromoxynil so that reduction in yields of broadleaf weeds and increases in alfalfa were similar to those obtained with 2,4-DB. At equivalent rates 3,5-dichloro-4-hydroxybenzonitrile (hereinafter referred to as chloroxynil) was less effective than bromoxynil for controlling broadleaf weeds and also was less injurious to alfalfa. When no weeds were present at time of application, bromoxynil at a rate of 0.56 kg/ha or greater and chloroxynil at 0.84 and 1.12 kg/ha significantly reduced yields of red clover (Trifolium pratense L.). When weeds were present bromoxynil did not reduce yields of red clover until the 1.12-kg rate was reached. Chloroxynil did not reduce yields at rates as high as 1.12 kg/ha. Excellent control of common lambsquarter (Chenopodium album L.) and common ragweed (Ambrosia artemisiifolia L.) was obtained, and no reduction in alfalfa or red clover occurred with 0.28 kg/ha of bromoxynil or chloroxynil mixed with 0.56 kg/ha of 2,4-DB ester.


Weed Science ◽  
2017 ◽  
Vol 65 (6) ◽  
pp. 699-709 ◽  
Author(s):  
Nick T. Harre ◽  
Haozhen Nie ◽  
Renae R. Robertson ◽  
William G. Johnson ◽  
Stephen C. Weller ◽  
...  

Giant ragweed is a highly competitive weed that continually threatens crop production systems due to evolved resistance to acetolactate synthase–inhibiting herbicides (ALS-R) and glyphosate (GR). Two biotypes of GR giant ragweed exist and are differentiated by their response to glyphosate, termed here as rapid response (RR) and non–rapid response (NRR). A comparison of data from surveys of Indiana crop fields done in 2006 and 2014 showed that GR giant ragweed has spread from 15% to 39% of Indiana counties and the NRR biotype is the most prevalent. A TaqMan®single-nucleotide polymorphism genotyping assay was developed to identify ALS-R populations and revealed 47% of GR populations to be ALS-R as well. The magnitude of glyphosate resistance for NRR populations was 4.6 and 5.9 based on GR50and LD50estimates, respectively. For RR populations, these values were 7.8 to 9.2 for GR50estimates and 19.3 to 22.3 for LD50estimates. A novel use of the Imaging-PAM fluorometer was developed to discriminate RR plants by assessing photosystem II quantum yield across the entire leaf surface. H2O2generation in leaves of glyphosate-treated plants was also measured by 3,3′-diaminobenzidine staining and quantified using imagery analysis software. Results show photo-oxidative stress of mature leaves is far greater and occurs more rapidly following glyphosate treatment in RR plants compared with NRR and glyphosate-susceptible plants and is positively associated with glyphosate dose. These results suggest that under continued glyphosate selection pressure, the RR biotype may surpass the NRR biotype as the predominant form of GR giant ragweed in Indiana due to a higher level of glyphosate resistance. Moreover, the differential photo-oxidative stress patterns in response to glyphosate provide evidence of different mechanisms of resistance present in RR and NRR biotypes.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Amy H. Poirier ◽  
Alan C. York ◽  
David L. Jordan ◽  
Aman Chandi ◽  
Wesley J. Everman ◽  
...  

Glyphosate resistance in Palmer amaranth was first confirmed in North Carolina in 2005. A survey that year indicated 17 and 18% of 290 populations sampled were resistant to glyphosate and thifensulfuron, respectively. During the fall of 2010, 274 predetermined sites in North Carolina were surveyed to determine distribution of Palmer amaranth and to determine if and where resistance to fomesafen, glufosinate, glyphosate, and thifensulfuron occurred. Palmer amaranth was present at 134 sites. When mortality for each biotype was compared to a known susceptible biotype for each herbicide within a rate, 93 and 36% of biotypes were controlled less by glyphosate (840 g ae ha−1) and thifensulfuron (70 g ai ha−1), respectively. This approach may have underestimated resistance for segregating populations due to lack of homogeneity of the herbicide resistance trait and its contribution to error variance. When mortality and visible control were combined, 98% and 97% of the populations were resistant to glyphosate and the ALS inhibitor thifensulfuron, respectively, and 95% of the populations expressed multiple resistance to both herbicides. This study confirms that Palmer amaranth is commonly found across the major row crop production regions of North Carolina and that resistance to glyphosate and ALS-inhibiting herbicides is nearly universal. No resistance to fomesafen or glufosinate was observed.


2017 ◽  
Vol 324 ◽  
pp. 436-447 ◽  
Author(s):  
Sagor Biswas ◽  
William L. Kranz ◽  
Charles A. Shapiro ◽  
Daniel D. Snow ◽  
Shannon L. Bartelt-Hunt ◽  
...  

2016 ◽  
Vol 30 (2) ◽  
pp. 516-523 ◽  
Author(s):  
Jialin Yu ◽  
Patrick E. McCullough

Turfgrass managers can reduce foliar bleaching of smooth crabgrass from mesotrione by tank-mixing triclopyr ester with applications. These tank mixtures also have potential to enhance smooth crabgrass control compared to mesotrione alone. The objectives of this research were to evaluate the influence of triclopyr on the efficacy, absorption, and translocation of mesotrione in multitiller smooth crabgrass. In field experiments, tank-mixing triclopyr at 560 or 1,120 g ae ha−1with mesotrione at 140 g ai ha−1applied sequentially or at 280 g ha−1applied singly provided excellent control (> 90%) of multitiller smooth crabgrass in tall fescue. These treatments were more effective than mesotrione alone and fenoxaprop at 195 g ai ha−1that averaged 66 and 81% control after 6 wk, respectively. Mesotrione alone at 280 g ha−1bleached smooth crabgrass 53% at 2 wk after initial treatment (WAIT), and was 14% greater than the 140 g ha−1treatment. Sequential treatments of the low mesotrione rate bleached smooth crabgrass 16 to 22% from 3 to 5 WAIT. Triclopyr tank mixtures reduced smooth crabgrass bleaching from mesotrione on all dates to < 5%. Tall fescue injury was not detected at any evaluation date. In laboratory experiments, smooth crabgrass reached peak foliar absorption of14C-mesotrione at 24 and 168 h after treatment (HAT; 23% and 15%) when mesotrione was applied with triclopyr at 1,120 and 0 g ha−1, respectively. Triclopyr reduced translocation of radioactivity 12% at 72 and 168 HAT, compared to14C-mesotrione alone. Enhanced foliar uptake of mesotrione from triclopyr tank mixtures might improve control of multitiller smooth crabgrass compared to mesotrione alone. Reduced foliar bleaching from triclopyr is associated with less translocation of mesotrione or derivatives in smooth crabgrass.


2015 ◽  
Vol 29 (2) ◽  
pp. 318-328 ◽  
Author(s):  
Amar S. Godar ◽  
Phillip W. Stahlman

Glyphosate is the leading herbicide used in glyphosate-resistant (GR) crops and no-till production systems. Evolved resistance to glyphosate in kochia was first reported in Kansas in 2007. Shortly thereafter, GR kochia became prevalent in western Kansas. An online survey of crop consultants was conducted in fall 2012 to gain their perspectives on evolving glyphosate resistance in kochia in western Kansas, to gather information on how grower weed management practices have changed from before to after occurrence of GR kochia, and to assess the effectiveness of management practices used during 2011 to 2012. Results of the survey indicated increasing infestation of kochia from prior to 2007 (present in 47% of fields) through 2012 (present in 70% of fields). It was estimated that greater than one-third of the cropland in western Kansas was thought to be infested with GR kochia by 2012. Growers increased glyphosate use rates from an average of 0.8 to 1.22 kg ae ha−1and application frequencies from 2.0 to 2.9 from the period before 2007 to 2012. The spread of GR kochia has resulted in changing weed management practices. During the survey period, growers reduced the exclusive use of glyphosate from 49 to 15% for GR crop fields and diversified weed management practices. Though other herbicides in addition to or in place of glyphosate were often applied prior to kochia emergence and were effective in more than half the fields, at least one-fourth of respondents reported inconsistent results with alternative kochia control practices other than tillage. These results are educational and helpful in developing both proactive and reactive tactics to manage GR kochia.


Weed Science ◽  
1982 ◽  
Vol 30 (3) ◽  
pp. 231-234 ◽  
Author(s):  
Albert E. Smith

The influence of herbicide formulation and time of herbicide application on smutgrass [Sporobolus poiretii(Roem. & Schult.) Hitchc.] control and phytotoxicity to the major perennial forage-grass species were determined. Dalapon (2,2-dichloropropionic acid) applied at rates of 4.8 kg/ha and higher gave excellent control regardless of time of application. However, 4.8 kg/ha dalapon applied to Pensacola bahiagrass (Paspalum notátumFlügg ‘Pensacola′) and bermudagrass [Cynodon dactylon(L.) Pers.] in the spring, and to tall fescue (Festuca arundinaceaSchreb. ‘Ky 31′) in the fall and spring, was phytotoxic. Applications of tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} 80W (80% wettable powder) formulation at 2.4 kg/ha, or fertilizer coated with tebuthiuron at 2.4 kg/ha, gave excellent smutgrass control. The pelleted formulation of tebuthiuron was less phytotoxic to the forage species than the other formulations.


Sign in / Sign up

Export Citation Format

Share Document