Winter Annual Broadleaf Weeds and Winter Wheat Response to Postemergence Application of Two Saflufenacil Formulations

2010 ◽  
Vol 24 (4) ◽  
pp. 416-424 ◽  
Author(s):  
John C. Frihauf ◽  
Phillip W. Stahlman ◽  
Patrick W. Geier ◽  
Dallas E. Peterson
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Field Experiments ◽  
Weed Species ◽  
Herbicide Resistant ◽  
Water Dispersible ◽  
Leaf Necrosis ◽  
Winter Annual ◽  
Rate Formulation ◽  
Water Dispersible Granule

Field experiments in winter wheat were initiated at two locations in the fall of 2006 and 2007 to evaluate winter annual broadleaf weeds and winter wheat response to POST applications of two saflufenacil formulations applied alone and in combination with 2,4-D amine. Emulsifiable concentrate (EC) and water-dispersible granule (WG) formulations of saflufenacil at 13, 25, and 50 g ai ha−1were applied with 1.0% (v/v) crop oil concentrate (COC) and mixed with 2,4-D amine at 533 g ae ha−1without adjuvant. Regardless of rate or formulation, saflufenacil plus COC and saflufenacil plus 2,4-D amine controlled blue mustard ≥ 91% at 17 to 20 d after treatment (DAT) compared with ≤ 50% control with 2,4-D amine alone. At least 25 g ha−1of saflufenacil EC was necessary to control flixweed > 90%. Excluding COC from saflufenacil plus 2,4-D amine reduced flixweed control from the saflufenacil WG formulation more than the EC formulation. Most saflufenacil treatments did not control henbit satisfactorily (≤ 80%). Wheat foliar necrosis increased with increasing saflufenacil rate to as high as 30% at 3 to 6 DAT, but declined to < 15% at 10 to 20 DAT and was not evident at 30 DAT. Saflufenacil rate, formulation, and mixing with 2,4-D amine also influenced wheat stunting, but to a lesser extent than foliar necrosis. Saflufenacil EC consistently caused greater foliar necrosis and stunting on wheat than saflufenacil WG. Leaf necrosis and stunting were reduced by tank-mixing saflufenacil formulations with 2,4-D amine without COC. Grain yields of most saflufenacil treatments were similar to 2,4-D amine under weedy conditions and herbicide treatments had no effect on grain yield in weed-free experiments. Saflufenacil formulations at 25 to 50 g ha−1with 2,4-D amine and saflufenacil WG at 25 to 50 g ha−1with COC can control winter annual broadleaf weeds with minimal injury (< 15%) and no grain yield reductions. The addition of saflufenacil as a POST-applied herbicide would give wheat growers another useful tool to control annual broadleaf weeds, including herbicide-resistant weed species.

scholarly journals Mechanical weed control in organic winter wheat

2017 ◽  
Vol 11 ◽  
Author(s):  
Euro Pannacci ◽  
Francesco Tei ◽  
Marcello Guiducci
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Weed Control ◽  
Field Experiments ◽  
Central Italy ◽  
Ground Cover ◽  
Farming Systems ◽  
Row Spacing ◽  
Weed Species ◽  
Mechanical Weed Control

Three field experiments were carried out in organic winter wheat in three consecutive years (exp. 1, 2005-06; exp. 2, 2006-07; exp. 3, 2007-08) in central Italy (42°57' N - 12°22' E, 165 m a.s.l.) in order to evaluate the efficacy against weeds and the effects on winter wheat of two main mechanical weed control strategies: 1) spring tine harrowing used at three different application times (1 passage at T1; 2 passages at the time T1; 1 passage at T1 followed by 1 passage at T1 + 14 days) in the crop sowed at narrow (traditional) row spacing (0.15 m) and 2) split-hoeing and finger-weeder, alone and combined at T1, in the crop sowed at wider row spacing (0.30 m). At the time T1 winter wheat was at tillering and weeds were at the cotyledons-2 true leaves growth stage. The experimental design was a split-plot with four replicates. Six weeks after mechanical treatments, weed ground cover (%) was rated visually using the Braun–Blanquet cover-abundance scale; weeds on three squares (0.6 x 0.5 m each one) per plot were collected, counted, weighed, dried in oven at 105 °C to determine weed density and weed above-ground dry biomass. At harvest, wheat ears density, grain yield, weight of 1000 seeds and hectolitre weight were recorded. Total weed flora was quite different in the three experiments. The main weed species were: <em>Polygonum aviculare</em> L. (exp. 1 and 2), <em>Fallopia convolvulus</em> (L.) Á. Löve (exp. 1 and 3), <em>Stachys annua</em> (L.) L. (exp. 1), <em>Anagallis arvensis</em> L. (exp. 2), <em>Papaver rhoeas</em> L. (exp.3), <em>Veronica hederifolia</em> L. (exp. 3). In the winter wheat sowed at narrow rows, 2 passages with spring-tine harrowing at the same time seems to be the best option in order to reconcile a good efficacy with the feasibility of treatment. In wider rows spacing the best weed control was obtained by splithoeing alone or combined with finger-weeder. The grain yield, on average 10% higher in narrow rows, the lower costs and the good selectivity of spring-tine harrowing treatments seems to suggest the adoption of narrow rows spacing in wheat in organic and low-input farming systems.

Effects of density and spatial pattern of winter wheat on suppression of different weed species

Weed Science ◽  
2005 ◽  
Vol 53 (5) ◽  
pp. 690-694 ◽  
Author(s):  
Jannie Olsen ◽  
Lars Kristensen ◽  
Jacob Weiner
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Field Experiments ◽  
Uniform Grid ◽  
First Year ◽  
Weed Species ◽  
Weed Biomass ◽  
Uniform Pattern ◽  
Growing Seasons ◽  
Total Crop

Field experiments on suppression of three species (scentless chamomile, field poppy, and canola) by winter wheat sown in two different spatial patterns (normal 12.8-cm rows and a uniform, grid-like pattern) and three densities (204, 449, and 721 plants m−2) in two growing seasons were performed. The effects of crop-sowing density and pattern when weeds were controlled by herbicide were also investigated in one season. Weed and crop biomass were measured when weed biomass was at its maximum (late June/early July), and grain was harvested in August. Weed biomass comprised on average 30% of the total (crop + weed) biomass in the first year and only 5% in the second year. Weed biomass decreased and grain yield increased with increasing sowing density. Weed biomass was on average 23% lower and grain yield 14% higher in the uniform pattern than in rows. Weed biomass decreased 27% and 38% in the row pattern and 36% and 50% in the uniform pattern by increasing sowing density from low to medium and from low to high density, respectively. When weeds were controlled with herbicide, increasing sowing density had no influence on grain yield, but grain yield was 7% higher in the uniform pattern. Field poppy was the weed with the largest biomass and the largest impact on yield, whereas canola had the lowest biomass and the least impact on yield.

scholarly journals Rattail fescue (Vulpia myuros) interference and seed production as affected by sowing time and crop density in winter wheat

Weed Science ◽  
2020 ◽  
pp. 1-10
Author(s):  
Muhammad Javaid Akhter ◽  
Per Kudsk ◽  
Solvejg Kopp Mathiassen ◽  
Bo Melander
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Seed Production ◽  
Yield Components ◽  
Field Experiments ◽  
Growing Season ◽  
Sowing Time ◽  
Growing Seasons ◽  
Crop Density ◽  
Wide Range

Abstract Field experiments were conducted in the growing seasons of 2017 to 2018 and 2018 to 2019 to evaluate the competitive effects of rattail fescue [Vulpia myuros (L.) C.C. Gmel.] in winter wheat (Triticum aestivum L.) and to assess whether delayed crop sowing and increased crop density influence the emergence, competitiveness, and fecundity of V. myuros. Cumulative emergence showed the potential of V. myuros to emerge rapidly and under a wide range of climatic conditions with no effect of crop density and variable effects of sowing time between the two experiments. Grain yield and yield components were negatively affected by increasing V. myuros density. The relationship between grain yield and V. myuros density was not influenced by sowing time or by crop density, but crop–weed competition was strongly influenced by growing conditions. Due to very different weather conditions, grain yield reductions were lower in the growing season of 2017 to 2018 than in 2018 to 2019, with maximum grain yield losses of 22% and 50% in the two growing seasons, respectively. The yield components, number of crop ears per square meter, and 1,000-kernel weight were affected almost equally, reflecting that V. myuros’s competition with winter wheat occurred both early and late in the growing season. Seed production of V. myuros was suppressed by delaying sowing and increasing crop density. The impacts of delayed sowing and increasing crop density on seed production of V. myuros highlight the potential of these cultural weed control tactics in the long-term management programs of this species.

Halauxifen-methyl controls glyphosate-resistant horseweed (Conyza canadensis) but not giant ragweed (Ambrosia trifida) in winter wheat

2020 ◽  
Vol 34 (4) ◽  
pp. 607-612 ◽  
Author(s):  
Jessica Quinn ◽  
Nader Soltani ◽  
Jamshid Ashigh ◽  
David C. Hooker ◽  
Darren E. Robinson ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Weed Management ◽  
Field Experiments ◽  
The United States ◽  
Integrated Weed Management ◽  
Conyza Canadensis ◽  
Limited Information ◽  
Weed Species ◽  
Ambrosia Trifida ◽  
Giant Ragweed

AbstractHorseweed is a competitive summer or winter annual weed that produces up to 230,000 small seeds per plant that are capable of traveling more than 500 km via wind. Giant ragweed is a tall, highly competitive summer annual weed. Glyphosate-resistant (GR) horseweed and GR giant ragweed pose significant challenges for producers in the United States and Ontario, Canada. It is thought that an integrated weed management (IWM) system involving herbicide rotation is required to control GR biotypes. Halauxifen-methyl is a new selective broadleaf POST herbicide registered for use in cereal crops; there is limited information on its efficacy on horseweed and giant ragweed. The purpose of this research was to determine the efficacy of halauxifen-methyl applied POST, alone and in a tank mix, for the control of GR horseweed and GR giant ragweed in wheat across southwestern Ontario. For each weed species, an efficacy study consisting of six field experiments was conducted over a 2-yr period (2018, 2019). At 8 wk after application (WAA), halauxifen-methyl, fluroxypyr/halauxifen-methyl, fluroxypyr/halauxifen-methyl + MCPA EHE, fluroxypyr + MCPA ester, 2,4-D ester, clopyralid, and pyrasulfotole/bromoxynil + ammonium sulfate controlled GR horseweed >95%. Fluroxypyr and MCPA provided only 86% and 37% control of GR horseweed, respectively. At 8 WAA, fluroxypyr, fluroxypyr/halauxifen-methyl, fluroxypyr/halauxifen-methyl + MCPA EHE, fluroxypyr + MCPA ester, fluroxypyr/halauxifen-methyl + MCPA EHE + pyroxsulam, 2,4-D ester, clopyralid, and thifensulfuron/tribenuron + fluroxypyr + MCPA ester controlled GR giant ragweed 87%, 88%, 90%, 94%, 96%, 96%, 98%, and 93%, respectively. Halauxifen-methyl and pyroxsulam provided only 45% and 28% control of GR giant ragweed, respectively. Halauxifen-methyl applied alone POST in the spring controlled GR horseweed but not GR giant ragweed in winter wheat.

scholarly journals Effect of Application Timing on Winter Wheat Response to Metribuzin

2017 ◽  
Vol 31 (1) ◽  
pp. 94-99 ◽  
Author(s):  
Mark J. VanGessel ◽  
Quintin R. Johnson ◽  
Barbara A. Scott
Keyword(s):  
Winter Wheat ◽  
Yield Loss ◽  
Early Spring ◽  
Growth Stages ◽  
Wheat Cultivars ◽  
Weed Species ◽  
Application Timing ◽  
Herbicide Resistant ◽  
Stage 4 ◽  
Stage 1

Metribuzin will control many problematic weed species in winter wheat in the mid-Atlantic states, including herbicide-resistant biotypes, but it has not been recommended due to crop safety concerns. In a three-year trial, metribuzin was applied at 105 or 210 g ai ha−1to wheat at the PRE, 2-leaf (Feekes stage 1 to 2), early spring (Feekes stage 3 to 4), and late spring (Feekes stage 4 to 6) growth stages using wheat cultivars sensitive to metribuzin. Early spring applications had the least amount of injury, and injury at this timing was transient and yield was not reduced. Yield loss was observed with the other application timings in at least one out of three years. Rainfall shortly after application appears to increase the risk of wheat injury.

Soft Red Winter Wheat (Triticum aestivum) Response to Dicamba and Dicamba Plus 2,4-D

1989 ◽  
Vol 3 (1) ◽  
pp. 67-71 ◽  
Author(s):  
Jill Schroeder ◽  
Philip A. Banks
Keyword(s):  
Triticum Aestivum ◽  
Winter Wheat ◽  
Grain Yield ◽  
Field Experiments ◽  
Wheat Cultivars ◽  
Soft Red Winter Wheat ◽  
Winter Wheat Cultivars ◽  
Red Winter Wheat

Soft red winter wheat cultivars were evaluated in field experiments in Georgia for tolerance to dicamba alone and mixed with 2,4-D. Treatments reduced ‘Florida 302’ yield more than ‘Florida 301’ or ‘Coker 983’ at Tifton in 1986. Mid-tillering Florida 302 wheat was more sensitive to treatment than fully tillered wheat. In 1987, dicamba plus 2,4-D applied at mid-tillering reduced yields of all cultivars in Watkinsville. Injury and yield reductions occurred primarily when mid-tiller treatments were applied to wheat that was planted 10 or 21 days later than recommended at Tifton or Watkinsville, respectively. When applied according to labeling, dicamba or dicamba plus 2,4-D use in Georgia soft red winter wheat can reduce grain yield.

scholarly journals Seed retention of winter annual grass weeds at winter wheat harvest maturity shows potential for harvest weed seed control

2019 ◽  
Vol 34 (2) ◽  
pp. 266-271 ◽  
Author(s):  
Neeta Soni ◽  
Scott J. Nissen ◽  
Philip Westra ◽  
Jason K. Norsworthy ◽  
Michael J. Walsh ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Great Plains ◽  
Downy Brome ◽  
Annual Grass ◽  
Weed Seed ◽  
Weed Species ◽  
Jointed Goatgrass ◽  
Seed Retention ◽  
Winter Annual ◽  
Feral Rye

AbstractDowny brome, feral rye, and jointed goatgrass are problematic winter annual grasses in central Great Plains winter wheat production. Integrated control strategies are needed to manage winter annual grasses and reduce selection pressure exerted on these weed populations by the limited herbicide options currently available. Harvest weed-seed control (HWSC) methods aim to remove or destroy weed seeds, thereby reducing seed-bank enrichment at crop harvest. An added advantage is the potential to reduce herbicide-resistant weed seeds that are more likely to be present at harvest, thereby providing a nonchemical resistance-management strategy. Our objective was to assess the potential for HWSC of winter annual grass weeds in winter wheat by measuring seed retention at harvest and destruction percentage in an impact mill. During 2015 and 2016, 40 wheat fields in eastern Colorado were sampled. Seed retention was quantified and compared per weed species by counting seed retained above the harvested fraction of the wheat upper canopy (15 cm and above), seed retained below 15 cm, and shattered seed on the soil surface at wheat harvest. A stand-mounted impact mill device was used to determine the percent seed destruction of grass weed species in processed wheat chaff. Averaged across both years, seed retention (±SE) was 75% ± 2.9%, 90% ± 1.7%, and 76% ± 4.3% for downy brome, feral rye, and jointed goatgrass, respectively. Seed retention was most variable for downy brome, because 59% of the samples had at least 75% seed retention, whereas the proportions for feral rye and jointed goatgrass samples with at least 75% seed retention were 93% and 70%, respectively. Weed seed destruction percentages were at least 98% for all three species. These results suggest HWSC could be implemented as an integrated strategy for winter annual grass management in central Great Plains winter wheat cropping systems.

Winter Annual Weed Suppression in Rye–Vetch Cover Crop Mixtures

2012 ◽  
Vol 26 (4) ◽  
pp. 818-825 ◽  
Author(s):  
Zachary D. Hayden ◽  
Daniel C. Brainard ◽  
Ben Henshaw ◽  
Mathieu Ngouajio
Keyword(s):  
Cover Crops ◽  
Cover Crop ◽  
Field Experiments ◽  
Dry Weight ◽  
Weed Suppression ◽  
Weed Species ◽  
Cereal Rye ◽  
Winter Annual ◽  
Winter Annual Weeds ◽  
Annual Weeds

Winter annual weeds can interfere directly with crops and serve as alternative hosts for important pests, particularly in reduced tillage systems. Field experiments were conducted on loamy sand soils at two sites in Holt, MI, between 2008 and 2011 to evaluate the relative effects of cereal rye, hairy vetch, and rye–vetch mixture cover crops on the biomass and density of winter annual weed communities. All cover crop treatments significantly reduced total weed biomass compared with a no-cover-crop control, with suppression ranging from 71 to 91% for vetch to 95 to 98% for rye. In all trials, the density of nonmustard family broadleaf weeds was either not suppressed or suppressed equally by all cover crop treatments. In contrast, the density of mustard family weed species was suppressed more by rye and rye–vetch mixtures than by vetch. Cover crops were more consistently suppressive of weed dry weight per plant than of weed density, with rye-containing cover crops generally more suppressive than vetch. Overall, rye was most effective at suppressing winter annual weeds; however, rye–vetch mixtures can match the level of control achieved by rye, in addition to providing a potential source of fixed nitrogen for subsequent cash crops.

Buckwheat Residue Effects on Emergence and Growth of Weeds in Winter-Wheat (Triticum aestivum) Cropping Systems

Weed Science ◽  
2011 ◽  
Vol 59 (4) ◽  
pp. 567-573 ◽  
Author(s):  
Virender Kumar ◽  
Daniel C. Brainard ◽  
Robin R. Bellinder ◽  
Russell R. Hahn
Keyword(s):  
New York ◽  
Winter Wheat ◽  
Weed Management ◽  
Cropping Systems ◽  
Soil Surface ◽  
Bare Soil ◽  
Weed Species ◽  
Winter Annual ◽  
Winter Annual Weeds ◽  
Annual Weeds

Field and pot studies were conducted in Central New York to determine the potential weed-management benefits of a buckwheat cover crop grown before winter wheat. Specific objectives were to determine buckwheat residue effects on (1) emergence and growth of winter annual weeds; (2) wheat establishment and yield; and (3) emergence of summer annual weeds in the spring following overwinter seed burial. In a field study, buckwheat was sown at two timings (July or August), mowed, and either incorporated or left on the soil surface. Winter wheat was drilled into buckwheat residue in September and weed and crop growth were monitored. In a complementary pot study, four winter annual weeds were sown in soil removed from buckwheat and bare-soil plots at 0 or 15 d after incorporation and monitored for emergence and early growth. To assess buckwheat residue effects on spring emergence from overwintering seeds, seeds of three weed species were buried in buckwheat residue and bare-soil plots in the fall, exhumed in April, and evaluated for emergence. To investigate the mechanism for possible effects of buckwheat residue on overwintering seeds, two levels each of seed treatment (none or fungicide) and fertilization (none or 170 kg ha−1) were applied before burial. Buckwheat residue had no negative effect on wheat yields but suppressed emergence (22 to 72%) and growth (0 to 95%) of winter annual weeds, although effects were often small and inconsistent. Buckwheat residue had no effect on the emergence of buried weed seeds in spring. However, fungicide treatment enhanced the emergence of Powell amaranth seeds by 12.5 to 25.5% and of barnyardgrass seeds by 0 to 12%. Our results suggest that buckwheat residue can contribute to weed management in wheat cropping systems, but that further studies investigating the mechanistic basis for the inconsistent selective effects of buckwheat residue on weeds are needed before buckwheat use can be optimized.

Imazamox for Winter Annual Grass Control in Imidazolinone-Tolerant Winter Wheat

2004 ◽  
Vol 18 (4) ◽  
pp. 924-930 ◽  
Author(s):  
Patrick W. Geier ◽  
Phillip W. Stahlman ◽  
Anthony D. White ◽  
Stephen D. Miller ◽  
Craig M. Alford ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Field Experiments ◽  
Wheat Yield ◽  
Early Spring ◽  
Annual Grass ◽  
Application Timing ◽  
Jointed Goatgrass ◽  
Early Fall ◽  
Winter Annual ◽  
Feral Rye

Field experiments were conducted at five locations in Kansas, Nebraska, and Wyoming to determine the effects of imazamox rate and application timing on winter annual grass control and crop response in imidazolinone-tolerant winter wheat. Imazamox at 35, 44, or 53 g ai/ha applied early-fall postemergence (EFP), late-fall postemergence, early-spring postemergence (ESP), or late-spring postemergence (LSP) controlled jointed goatgrass at least 95% in all experiments. Feral rye control with imazamox was 95 to 99%, regardless of rate or application timing at Hays, KS, in 2001. Feral rye control at Sidney, NE, and Torrington, WY, was highest (78 to 85%) with imazamox at 44 or 53 g/ha. At Sidney and Torrington, feral rye control was greatest when imazamox was applied EFP. Imazamox stunted wheat <10% in two experiments at Torrington, but EFP or LSP herbicide treatments in the Sidney experiment and ESP or LSP treatments in two Hays experiments caused moderate (12 to 34%) wheat injury. Wheat injury increased as imazamox rate increased. Wheat receiving imazamox LSP yielded less grain than wheat treated at other application timings in each Hays experiment and at Sidney in 2001. No yield differences occurred in one Torrington experiment. However, yields generally decreased as imazamox application timing was delayed in the other Torrington experiment. Generally, imazamox applied in the fall provided the greatest weed control, caused the least wheat injury, and maximized wheat yield.

Sign in / Sign up

Export Citation Format

Share Document