scholarly journals Winter Annual Grass Control in Winter Wheat

2017 ◽  
Vol 3 (6) ◽  
Author(s):  
D. E. Peterson ◽  
C. Thompson ◽  
C. L. Minihan
Keyword(s):  
Winter Wheat ◽  
Annual Grass ◽  
Winter Annual

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.

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.

Dose-Responses of Weeds and Winter Wheat (Triticum aestivum) to MON 37500

1996 ◽  
Vol 10 (4) ◽  
pp. 870-875 ◽  
Author(s):  
Patrick W. Geier ◽  
Phillip W. Stahlman
Keyword(s):  
Winter Wheat ◽  
Residual Effects ◽  
Downy Brome ◽  
Annual Grass ◽  
Jointed Goatgrass ◽  
Weed Growth ◽  
Annual Grasses ◽  
Winter Annual ◽  
Dose Responses ◽  
Weed Emergence

Greenhouse studies determined the dose-responses of cheat, downy brome, Japanese brome, jointed goatgrass, and winter wheat to preplant-incorporated MON 37500 and its residual effects on kochia. Concentrations of MON 37500 up to 60 ppbw did not affect winter wheat. MON 37500 did not prevent weed emergence, but increasingly inhibited weed growth as the dose was increased up to about 20 ppbw. GR50values were 16, 16, 11, and 31 ppbw for cheat, downy brome, Japanese brome, and jointed goatgrass, respectively. Japanese brome was more susceptible than cheat or downy brome, and jointed goatgrass tolerated two to three times more MON 37500 than theBromusspecies. Plant dry weights of kochia seeded after removal of the winter annual grasses decreased with increasing initial MON 37500 concentrations up to 20 ppbw. Kochia density was influenced by which winter annual grass was grown previously.

Cropping Systems Control Winter Annual Grass Weeds in Winter Wheat

jpa ◽  
1995 ◽  
Vol 8 (4) ◽  
pp. 535-539 ◽  
Author(s):  
Drew J. Lyon ◽  
David D. Baltensperger
Keyword(s):  
Winter Wheat ◽  
Cropping Systems ◽  
Annual Grass ◽  
Winter Annual ◽  
Systems Control

Characterizing traits that enhance the competitiveness of winter wheat (Triticum aestivum) against jointed goatgrass (Aegilops cylindrica)

Weed Science ◽  
1999 ◽  
Vol 47 (1) ◽  
pp. 74-80 ◽  
Author(s):  
Alex G. Ogg ◽  
Steven S. Seefeldt
Keyword(s):  
Winter Wheat ◽  
Seed Production ◽  
Latent Variables ◽  
Annual Grass ◽  
Aegilops Cylindrica ◽  
Growing Seasons ◽  
Jointed Goatgrass ◽  
Important Trait ◽  
Winter Annual ◽  
Grass Weed

Our objective was to identify traits in winter wheat important to competitiveness against jointed goatgrass, measured as increased wheat yields and reduced jointed goatgrass seed production. Jointed goatgrass is an important winter annual grass weed that cannot be controlled selectively in winter wheat. Seven cultivars of soft white winter wheat were grown with and without competition from jointed goatgrass over two growing seasons. Measurements of numerous traits of winter wheat and jointed goatgrass were recorded throughout each growing season. The data were analyzed using path analysis with latent variables to determine which traits most enhanced competitiveness. In a drier year, increased rate of height development was important in maintaining wheat yields when wheat was growing in competition with jointed goatgrass. Increased rate of height development also was an important trait in reducing jointed goatgrass seed production. In a wet year compared to a dry year, the number of wheat heads per plant, the rate of water use, and weight gain were positively correlated to maintaining winter wheat yields. Jointed goatgrass seed production in the wet year was reduced overall compared to the dry year, but from the cultivars tested, there were no traits identified that were critical in enhancing this loss of seed production. This study suggests that cultivars with greater height development rates will be more competitive when growing in fields infested with jointed goatgrass.

Palweed:Wheat: A Bioeconomic Decision Model for Postemergence Weed Management in Winter Wheat (Triticum aestivum)

Weed Science ◽  
1995 ◽  
Vol 43 (4) ◽  
pp. 595-603 ◽  
Author(s):  
Tae-Jin Kwon ◽  
Douglas L. Young ◽  
Frank L. Young ◽  
Chris M. Boerboom
Keyword(s):  
Winter Wheat ◽  
Weed Management ◽  
Decision Model ◽  
Damage Function ◽  
Yield Response ◽  
Density Functions ◽  
Yield Model ◽  
Weed Density ◽  
Annual Grasses ◽  
Winter Annual

Based on six years of data from a field experiment near Pullman, WA, a bioeconomic decision model was developed to annually estimate the optimal post-emergence herbicide types and rates to control multiple weed species in winter wheat under various tillage systems and crop rotations. The model name, PALWEED:WHEAT, signifies a Washington-Idaho Palouse region weed management model for winter wheat The model consists of linear preharvest weed density functions, a nonlinear yield response function, and a profit function. Preharvest weed density functions were estimated for four weed groups: summer annual grasses, winter annual grasses, summer annual broadleaves, and winter annual broadleaves. A single aggregated weed competition index was developed from the four density functions for use functions for use in the yield model. A yield model containing a logistic damage function performed better than a model containing a rectangular hyperbolic damage function. Herbicides were grouped into three categories: preplant nonselective, postemergence broadleaf, and postemergence grass. PALWEED:WHEAT was applied to average conditions of the 6-yr experiment to predict herbicide treatments that maximized profit. In comparison to average treatment rates in the 6-yr experiment, the bioeconomic decision model recommended less postemergence herbicide. The weed management recommendations of PALWEED:WHEAT behaved as expected by agronomic and economic theory in response to changes in assumed weed populations, herbicide costs, crop prices, and possible restrictions on herbicide application rates.

Cropping Systems to Control Winter Annual Grasses in Winter Wheat (Triticum aestivum)

1999 ◽  
Vol 13 (1) ◽  
pp. 120-126 ◽  
Author(s):  
Oleg Daugovish ◽  
Drew J. Lyon ◽  
David D. Baltensperger
Keyword(s):  
Winter Wheat ◽  
Cropping Systems ◽  
Field Studies ◽  
Downy Brome ◽  
Jointed Goatgrass ◽  
Long Term Effect ◽  
Annual Grasses ◽  
Winter Annual ◽  
Feral Rye

Field studies were conducted from 1990 through 1997 to evaluate the long-term effect of 2- and 3-yr rotations on the control of downy brome, jointed goatgrass, and feral rye in winter wheat. At the completion of the study, jointed goatgrass and feral rye densities averaged 8 plants/m2and < 0.1 plant/m2for the 2- and 3-yr rotations, respectively. Downy brome densities averaged < 0.5 plant/m2for both the 2- and 3-yr rotations, with no treatment differences observed. Winter annual grasses were not eradicated after two cycles of the 3-yr rotations, but weed densities were reduced 10-fold compared to densities after one cycle and more than 100-fold compared with the 2-yr rotations. Wheat grain contamination with dockage and foreign material followed a similar trend. The 3-yr rotations were economically competitive with 2-yr rotations and provided superior control of the winter annual grass weeds.

Downy Brome (Bromus tectorum) Vernalization: Variation and Genetic Controls

Weed Science ◽  
2018 ◽  
Vol 66 (3) ◽  
pp. 310-316 ◽  
Author(s):  
Nevin C. Lawrence ◽  
Amber L. Hauvermale ◽  
Ian C. Burke
Keyword(s):  
North America ◽  
Bromus Tectorum ◽  
Brachypodium Distachyon ◽  
Western North America ◽  
Downy Brome ◽  
Annual Grass ◽  
Vernalization Gene ◽  
Greenhouse Experiments ◽  
Winter Annual

AbstractDowny brome (Bromus tectorumL.) is a widely distributed invasive winter annual grass across western North America.Bromus tectorumphenology can vary considerably among populations, and those differences are considered adaptively significant. A consensus hypothesis in the literature attributes the majority of observed differences inB. tectorumphenology to differing vernalization requirements among populations. A series of greenhouse experiments were conducted to identify differences inB. tectorumvernalization requirements and link vernalization to expression of annual false-brome [Brachypodium distachyon(L.) P. Beauv.]-derived vernalization gene homolog (BdVRN1). Results from this study indicate that variation in time to flowering is partially governed by differing vernalization requirements and that flowering is linked to the expression ofBdVRN1.

The Determinants of the Distribution and Abundance of the Winter Annual Grass Vulpia Ciliata ssp. Ambigua

1995 ◽  
Vol 83 (2) ◽  
pp. 177 ◽  
Author(s):  
P. D. Carey ◽  
A. R. Watkinson ◽  
F. F. O. Gerard
Keyword(s):  
Annual Grass ◽  
Winter Annual
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