Selective soil bacteria to manage downy brome, jointed goatgrass, and medusahead and do no harm to other biota

In the greenhouse, glyphosate [N-(phosphonomethyl)glycine] at 0.6 kg ae/ha applied directly to seeds alone or seeds on the soil surface reduced germination and shoot dry weight of common rye (Secale cerealeL. ♯3SECCE). Paraquat (1,1′-dimethyl-4,4′-bipyridinium ion) applied similarly at 0.6 kg ai/ha reduced germination and shoot dry weight of downy brome (Bromus tectorumL. ♯ BROTE) and wheat (Triticum aestivumL. ‘Daws' ♯ TRZAX). Metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5 (4H)-one] at 0.6 kg ai/ha applied to seeds, soil, or seeds and soil had very little effect on germination, but significantly reduced shoot dry weight of common rye, downy brome, wheat, and jointed goatgrass (Aegilops cylindricaHost. ♯ AEGCY). Pronamide [3,5-dichloro(N-1,1-dimethyl-2-propynyl)benzamide] at 0.6 kg ai/ha, and propham (isopropyl carbanilate) at 3.4 kg ai/ha plus extender (p-chlorophenyl-N-methylcarbamate) at 0.4 kg ai/ha substantially reduced shoot height and dry weight of all species, regardless of application method, with pronamide completely inhibiting shoot elongation and dry-weight production in three of the four species.

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

Weed Technology ◽

10.1017/s0890037x00045012 ◽

1999 ◽

Vol 13 (1) ◽

pp. 120-126 ◽

Cited By ~ 32

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.

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Selected Pacific Northwest Rangeland and Weed Plants as Hosts of Pratylenchus neglectus and P. thornei

Plant Disease ◽

10.1094/pdis-12-13-1295-re ◽

2014 ◽

Vol 98 (10) ◽

pp. 1333-1340 ◽

Cited By ~ 3

Author(s):

Richard W. Smiley ◽

Guiping Yan ◽

Jennifer A. Gourlie

Keyword(s):

Pacific Northwest ◽

Crop Production ◽

Production Systems ◽

Downy Brome ◽

Weed Species ◽

Nematode Density ◽

Pratylenchus Neglectus ◽

Jointed Goatgrass ◽

Green Foxtail

Eighteen rangeland plants and 16 weed species were assayed in the greenhouse for efficiency as hosts of Pratylenchus neglectus and P. thornei. Hosting ability ratings were assigned using the ratio of final versus initial nematode density and by comparing the final nematode density to that of susceptible wheat controls. Good hosts of both Pratylenchus spp. included thickspike bluegrass ‘Critana’, smooth brome ‘Manchar’, seven wheatgrasses, and jointed goatgrass. Good hosts of P. neglectus but not P. thornei included two hairy vetches, western wheatgrass ‘Rosana’, big bluegrass ‘Sherman’, tall wheatgrass ‘Alkar’, green foxtail, kochia, large crabgrass, palmer amaranth, redroot pigweed, tumble mustard, and wild oat. Good hosts of P. thornei but not P. neglectus included hard fescue ‘Durar’, sheep fescue ‘Blacksheep’, downy brome, and rattail fescue. Poor or minor hosts of both Pratylenchus spp. included two alfalfas, dandelion, horseweed, lambsquarters, prostrate spurge, and Russian thistle. These assays will provide guidance for transitioning rangeland into crop production and for understanding the role of weeds on densities of Pratylenchus spp. in wheat-production systems.

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Ecological Characteristics of Three Winter Annual Grasses

Weed Technology ◽

10.1017/s0890037x00044183 ◽

1998 ◽

Vol 12 (3) ◽

pp. 478-483 ◽

Cited By ~ 15

Author(s):

R. L. Anderson

Keyword(s):

Winter Wheat ◽

Seed Production ◽

Cultural Practices ◽

Seedling Emergence ◽

Cultural Control ◽

Downy Brome ◽

Jointed Goatgrass ◽

Annual Grasses ◽

Winter Annual ◽

Feral Rye

Producers rely on cultural practices to manage downy brome, jointed goatgrass, and feral rye in winter wheat because there are no effective herbicides for in-crop control. This study characterized seedling emergence, growth, and development of these winter annual grasses, with the goal of suggesting or improving cultural control strategies. Feral rye seedlings emerged within 4 wk, whereas downy brome and jointed goatgrass seedlings emerged over a 10-wk period. Emergence patterns of these grasses suggest that delay of winter wheat planting may be effective in reducing feral rye densities, but this strategy most likely will be ineffective with downy brome or jointed goatgrass. Downy brome began anthesis 1 to 2 wk earlier than the other two grasses and winter wheat. Both downy brome and jointed goatgrass were shorter than winter wheat during the growing season, whereas feral rye was at least as tall as wheat. Producers mow infested wheat to prevent weed seed production, but this practice may not be effective with jointed goatgrass and downy brome because of their short stature and downy brome's earlier development. Conversely, mowing has potential in preventing feral rye seed production. The grasses produced between 340 and 770 seeds/ plant.

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

Weed Technology ◽

10.1017/wet.2019.108 ◽

2019 ◽

Vol 34 (2) ◽

pp. 266-271 ◽

Cited By ~ 5

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.

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Seedling Emergence of Winter Annual Grasses as Affected by Limited Tillage and Crop Canopy

Weed Technology ◽

10.1017/s0890037x00043797 ◽

1998 ◽

Vol 12 (2) ◽

pp. 262-267 ◽

Cited By ~ 21

Author(s):

R. L. Anderson

Keyword(s):

Cultural Practices ◽

Soil Seed Bank ◽

Seedling Emergence ◽

First Year ◽

Downy Brome ◽

Crop Canopy ◽

Proso Millet ◽

Jointed Goatgrass ◽

Annual Grasses ◽

Tillage Operation

Jointed goatgrass and downy brome continue to plague winter wheat producers in the western United States. Because there are no effective herbicides for in-crop control of these weeds, producers are seeking cultural practices that stimulate seed germination and deplete the soil seed bank. We determined the effect of limited tillage and crop canopy on seedling emergence of these grasses. One tillage operation with a sweep plow increased jointed goatgrass seedling emergence 74% in the first year but did not affect emergence in later years. Downy brome emergence was not affected by tillage. Jointed goatgrass seedlings emerged over 5 yr, whereas downy brome did not emerge after 3 yr. Seedling emergence of both species was two times greater in corn and barley than in proso millet. Producers will accrue more benefit for seedbank management with cultural strategies such as alternative rotations and competitive wheat canopies than with limited tillage using a sweep plow.

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

Weed Technology ◽

10.1017/s0890037x0004094x ◽

1996 ◽

Vol 10 (4) ◽

pp. 870-875 ◽

Cited By ~ 12

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.

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Herbicide-Resistant Grass Weed Development in Imidazolinone-Resistant Wheat: Weed Biology and Herbicide Rotation

Weed Technology ◽

10.1614/wt-03-167r ◽

2004 ◽

Vol 18 (3) ◽

pp. 860-868 ◽

Cited By ~ 7

Author(s):

Curtis R. Rainbolt ◽

Donald C. Thill ◽

Joseph P. Yenish ◽

Daniel A. Ball

Keyword(s):

Winter Wheat ◽

Seed Bank ◽

Cropping Systems ◽

Soil Seed Bank ◽

Wild Oat ◽

Downy Brome ◽

Weed Biology ◽

Soil Seed Banks ◽

Herbicide Resistant ◽

Jointed Goatgrass

A general life cycle model was modified to demonstrate how agronomic practices and weed biology factors affect the rate of appearance of herbicide-resistant downy brome, jointed goatgrass, and wild oat in Pacific Northwest wheat cropping systems. The model suggests herbicide rotation strategies for cropping systems that include imidazolinone-resistant wheat as a weed management tool. Simulation of continuous annual imidazolinone-resistant winter wheat and imazamox herbicide use resulted in the resistant soil seed banks of downy brome, jointed goatgrass, and wild oat surpassing their susceptible soil seed banks in 5, 7, and 10 yr, respectively. Reducing the initial seed bank density of downy brome before beginning a rotation that includes imidazolinone-resistant winter wheat reduces the likelihood of selecting for herbicide-resistant biotypes. The best simulated management option for reducing the total jointed goatgrass soil seed bank in low-precipitation areas is an imidazolinone-resistant winter wheat–fallow rotation. Rotations that include winter and spring crops and rotations that include non–group 2 herbicides minimize herbicide resistance selection pressure and reduce the wild oat soil seed bank.

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Absorption and fate of BAY MKH 6561 in jointed goatgrass and downy brome

Weed Science ◽

10.1614/0043-1745(2001)049[0717:aafobm]2.0.co;2 ◽

2001 ◽

Vol 49 (6) ◽

pp. 717-722 ◽

Cited By ~ 6

Author(s):

Lynn Fandrich ◽

Sandra K. McDonald ◽

Scott J. Nissen ◽

Philip Westra ◽

Hans J. Santel

Keyword(s):

Downy Brome ◽

Jointed Goatgrass

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Effect of Temperature on Root Absorption of Metribuzin and its Ethylthio Analog by Winter Wheat (Triticum aestivum), Jointed Goatgrass (Aegilops cylindrica), and Downy Brome (Bromus tectorum)

Weed Science ◽

10.1017/s0043174500058069 ◽

1992 ◽

Vol 40 (4) ◽

pp. 517-521 ◽

Cited By ~ 6

Author(s):

Robert A. Buman ◽

David R. Gealy ◽

Alex G. Ogg

Keyword(s):

Winter Wheat ◽

Water Absorption ◽

Bromus Tectorum ◽

Dry Weight ◽

The Other ◽

Effect Of Temperature ◽

Downy Brome ◽

Aegilops Cylindrica ◽

Jointed Goatgrass ◽

Root Absorption

Root absorption of subtoxic levels of metribuzin and its ethylthio analog (ethyl-metribuzin) by downy brome, jointed goatgrass, and winter wheat increased by a factor of three to five times as temperature increased from 10 to 20 C. Absorption of ethyl-metribuzin per gram dry weight was similar for all three species. Absorption and distribution of ethyl-metribuzin, but not metribuzin, were similar per gram dry weight in downy brome and jointed goatgrass. Absorption of metribuzin per gram dry weight was lower for winter wheat than for the other two species at 20 C. In general, the ratio of absorbed ethyl-metribuzin detected in shoots to that in roots was less in winter wheat and jointed goatgrass than in downy brome. The absorption by roots of14C-herbicides relative to water was similar for winter wheat and jointed goatgrass. Absorption of both14C-herbicides by winter wheat and jointed goatgrass was nonpreferential with respect to water absorption at 10 and 15 C. However, at 20 C14C-herbicide absorption was reduced 5 to 30% with respect to water absorption. Downy brome absorption of14C-herbicides with respect to water was 30 to 50% less than that of the other two species.

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