Winter Wheat and Weed Response to Postemergence Saflufenacil Alone and in Mixtures

Growth chamber experiments were conducted in the fall of 2006 and spring of 2007 to determine winter wheat, flixweed, and henbit response to POST treatments of saflufenacil at 13, 25, and 50 g ai ha−1 applied alone and in combinations with bentazon at 560 g ai ha−1 or 2,4-D amine at 533 g ae ha−1 and nonionic surfactant (NIS) at 0.25% v/v. Mixtures of saflufenacil and 2,4-D amine were also applied without NIS. Necrosis was observed on wheat leaves within 1 d after treatment (DAT) and peaked at 5 to 7 DAT. Saflufenacil at 13, 25, or 50 g ai ha−1 applied alone or in combination with 533 g ae ha−1 of 2,4-D amine plus NIS caused 19 to 38% (alone) and 24 to 40% (in combination) wheat foliar necrosis, respectively. Foliar necrosis of wheat was 14% or less when saflufenacil, at any rate, was mixed with bentazon or 2,4-D amine without NIS. Combinations of saflufenacil at any of the rates tested plus bentazon and NIS did not reduce wheat dry weight. Saflufenacil plus 2,4-D amine without adjuvant resulted in similar wheat dry weights as 2,4-D amine. Saflufenacil plus 2,4-D amine without NIS provided 99% control of flixweed at 21 DAT, but henbit control ranged from 81 to 88%. In comparison, saflufenacil at 50 g ha−1 mixed with bentazon and NIS controlled flixweed at 92% and henbit at 63% at 21 DAT. This research indicates saflufenacil has potential for POST use in winter wheat to control winter annual broadleaf weeds when tank-mixed with 2,4-D amine without NIS, but additional research is needed to discover ways to improve crop safety without reducing weed control.

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Weed control in soybean (Glycine max) with imazamox and imazethapyr

Weed Science ◽

10.1017/s0043174500091141 ◽

1998 ◽

Vol 46 (5) ◽

pp. 587-594 ◽

Cited By ~ 18

Author(s):

Kelly A. Nelson ◽

Karen A. Renner ◽

Donald Penner

Keyword(s):

Nonionic Surfactant ◽

Weed Control ◽

Seed Oil ◽

Diphenyl Ether ◽

Soybean Seed ◽

Dry Weight ◽

Common Ragweed ◽

Common Lambsquarters ◽

Giant Foxtail ◽

Urea Ammonium Nitrate

Field and greenhouse experiments were conducted in 1995 and 1996 to determine soybean injury and weed control differences from imazamox and imazethapyr applied postemergence with a nonionic surfactant or methylated seed oil and with selected tank mixtures. Soybean injury from imazamox at 35 g ai ha−1plus either a methylated seed oil or nonionic surfactant was equal to injury from imazethapyr at 70 g ai ha−1in the greenhouse and field. Imazamox provided greater common lambsquarters control than imazethapyr in the field in 1995 and in the greenhouse. Thifensulfuron tank mixed with imazethapyr increased common lambsquarters control, while soybean response increased when thifensulfuron was tank mixed with imazamox. Common ragweed dry weight was reduced 61 to 64% from 35 g ha−1imazamox and 70 g ha−1imazethapyr in the field; however, imazamox provided greater common ragweed control than imazethapyr in the greenhouse. Tank mixtures of lactofen with imazamox or imazethapyr increased common ragweed control and resulted in greater soybean seed yield in 1996 than when imazamox and imazethapyr were applied alone; however, lactofen antagonized giant foxtail control with imazamox and imazethapyr, and antagonized common lambsquarters control with imazamox. Giant foxtail control in the greenhouse was antagonized more when acifluorfen, fomesafen, and lactofen were tank mixed with 35 g ha−1imazethapyr than with 35 g ha−1imazamox. Giant foxtail control with imazamox or imazethapyr applied alone or with diphenyl ether herbicides increased when 28% urea ammonium nitrate was added with nonionic surfactant compared with nonionic surfactant only. Imazethapyr antagonized giant foxtail control by clethodim in the field and was more antagonistic than imazamox in the greenhouse. A methylated seed oil improved common ragweed control by imazethapyr at 70 g ha−1and imazamox at 18 and 35 g ha−1, while common lambsquarters and velvetleaf control increased when a methylated seed oil was included with 18 g ha−1imazethapyr compared to nonionic surfactant in the greenhouse.

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Influence of mercury on chlorophyll content in winter wheat and mercury bioaccumulation

Plant Soil and Environment ◽

10.17221/210/2009-pse ◽

2010 ◽

Vol 56 (No. 3) ◽

pp. 139-143 ◽

Cited By ~ 16

Author(s):

D. Liu ◽

X. Wang ◽

Z. Chen ◽

H. Xu ◽

Y. Wang

Keyword(s):

Winter Wheat ◽

Chlorophyll Content ◽

Inductively Coupled Plasma ◽

Dry Weight ◽

High Concentration ◽

Field Mass ◽

Wheat Growth ◽

Inductively Coupled ◽

Mercury Bioaccumulation ◽

Wheat Leaves

Mercury (Hg) is one of the major pollutants in soils because of the annual import of toxic Hg into the agricultural lands. The aims of the present studies are to investigate the effect of Hg on chlorophyll content in winter wheat var. jinan No. 17. Moreover, calcium (Ca) levels and bioaccumulation of Hg in wheat leaves were studied with the technique of inductively coupled plasma sector field mass spectrometer (ICP-SF-MS). The study conducted a range of Hg concentrations from 0~500 mg Hg/kg in the dry weight soil. The soil was artificially contaminated with Hg as follows: 0, 100, 200, and 500 mg Hg/kg as HgCl<SUB>2</SUB>. At early stages of the wheat growth, both low and high concentration of Hg stimulates chlorophyll content, but inhibits chlorophyll content at later stages of the wheat growth. Furthermore, the concentrations of Ca and Hg in wheat leaves increased with the increasing concentration of Hg<SUP> </SUP>on the thirty-fourth day with the technique of ICP-SF-MS. The results indicate that Hg can accelerate the absorption of Ca in winter wheat and Hg stress may affect Ca levels in wheat leaves.

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Results from two experiments with winter wheat, comparing top-dressings of a liquid N-fertilizer either alone or with added herbicide or mildew fungicide or both, and of ‘Nitro-Chalk’ without or with the herbicide or fungicide or both

The Journal of Agricultural Science ◽

10.1017/s0021859600062419 ◽

1975 ◽

Vol 85 (3) ◽

pp. 533-539 ◽

Cited By ~ 6

Author(s):

A. Penny ◽

J. F. Jenkyn

Keyword(s):

Winter Wheat ◽

Weed Control ◽

Active Ingredient ◽

Growth Stage ◽

N Fertilizer ◽

The Other ◽

Liquid Fertilizer ◽

Foliar Diseases ◽

Stage 4 ◽

Wheat Leaves

SUMMARYExperiments with winter wheat in 1972 and 1973 tested all combinations of ‘Nitro-Chalk’ ν. liquid N-fertilizer, 56 ν. 112 kg N/ha, 0 ν 5·6 1/ha of herbicide (2·8 kg acid equivalent/ha) and 0 ν 0·7 1/ha of mildew fungicide, all applied at growth stage 4–5 of the Feekes scale. The liquid fertilizer (26 % N) was a solution of ammonium nitrate and urea, the herbicide was a mixture of dichlorprop and MCPA and the mildew fungicide contained 75 % (w/v) of the active ingredient tridemorph.The herbicide and mildew fungicide were sprayed either alone or together and neither scorched the wheat leaves. Liquid N-fertilizer by itself slightly scorched the wheat leaves and scorch was increased by adding herbicide to it, but more by adding the fungicide and most by adding both; it was then severe, especially with 112 kg N/ha.Weed control after adding herbicide to the liquid fertilizer was at least as good as from herbicide sprayed alone.In July, foliar diseases were much more severe with 112 than with 56 kg N/ha, but effects of the other treatments, including fungicide, on foliar diseases, were then very small.With 56 kg N/ha, yields were slightly larger with ‘Nitro-Chalk’ alone than with the liquid N-fertilizer alone, but with 112 kg N/ha they were slightly larger with the liquid fertilizer; adding herbicide to the liquid fertilizer did not change these results. With either amount of N, adding mildew fungicide to the liquid fertilizer made it less good than ‘Nitro-Chalk’, presumably because of the damage from leaf scorch; adding both herbicide and fungicide to the liquid fertilizer increased the damage.

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The Influence of Terbufos on Primisulfuron Absorption and Fate in Corn (Zea mays)

Weed Science ◽

10.1017/s0043174500076487 ◽

1993 ◽

Vol 41 (4) ◽

pp. 664-668 ◽

Cited By ~ 15

Author(s):

Todd L. Frazier ◽

Scott J. Nissen ◽

David A. Mortensen ◽

Lance J. Meinke

Keyword(s):

Zea Mays ◽

Nonionic Surfactant ◽

Half Life ◽

Culture System ◽

Dry Weight ◽

Shoot Length ◽

Growth Chamber ◽

Sand Culture ◽

Shoot Dry Weight ◽

Metabolite Profiles

Terbufos and primisulfuron interactions were evaluated under growth chamber conditions using a sand culture system. Terbufos was applied to transplanted corn seedlings, followed in 5 d by foliar applications of primisulfuron plus nonionic surfactant. Primisulfuron and terbufos alone did not cause corn injury; however, shoot dry weight and shoot length were reduced 28 and 36% in terbufos treatments 96 h after primisulfuron application. Primisulfuron absorption and translocation were not affected by terbufos, but the half-life of primisulfuron increased from 2 to 3.5 h in terbufos treatments. Terbufos did not affect primisulfuron metabolite profiles. The basis for increased primisulfuron phytotoxicity in terbufos treatments appeared to result from reduced primisulfuron metabolism.

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Common Ragweed (Ambrosia artemisiifolia) Control in Soybean (Glycine max) with Bentazon as Influenced by Imazethapyr or Thifensulfuron Tank-mixes

Weed Technology ◽

10.1017/s0890037x00028669 ◽

1994 ◽

Vol 8 (4) ◽

pp. 766-771 ◽

Cited By ~ 13

Author(s):

Aaron Hager ◽

Karen Renner

Keyword(s):

Glycine Max ◽

Nonionic Surfactant ◽

Ammonium Nitrate ◽

Weed Control ◽

Field Research ◽

Dry Weight ◽

Ambrosia Artemisiifolia ◽

Common Ragweed ◽

Urea Ammonium Nitrate ◽

Petroleum Oil

Several herbicides control common ragweed postemergence in soybean. However, weed response may be altered if herbicides are tank-mixed and the choice of additive may also influence the degree of weed control. Imazethapyr and thifensulfuron could be tank-mixed with bentazon for broadleaf weed control and visual crop injury reduced compared to a bentazon plus acifluorfen tank-mix. Experiments determined common ragweed control with these herbicides and herbicide combinations when applied with various additives. In the greenhouse, bentazon at 560 g ai/ha reduced common ragweed dry weight 95 to 97%. Common ragweed control with imazethapyr at 35 g/ha increased by 13 and 7% when 28% urea ammonium nitrate was applied with nonionic surfactant or petroleum oil adjuvant, respectively. Tank-mixing imazethapyr with bentazon did not change dry weight of common ragweed compared with bentazon. Bentazon plus thifensulfuron plus nonionic surfactant required the addition of 28% urea ammonium nitrate to reduce dry weight of common ragweed comparable to that with bentazon. In field research, bentazon at 1120 g/ha reduced common ragweed dry weight 78 to 81%. Tank-mixing bentazon with thifensulfuron at 4.5 g/ha or imazethapyr at 71 or 35 g/ha reduced common ragweed dry weight at 14 d after treatment by 89 to 91%, thus enhancing control compared to each herbicide applied alone. Adding 28% urea ammonium nitrate to bentazon plus imazethapyr or bentazon plus thifensulfuron tank-mixes did not increase control compared to these treatments applied with either nonionic surfactant or petroleum oil adjuvant. By 28 d after treatment only imazethapyr at 35 or 71 g/ha plus 28% urea ammonium nitrate plus nonionic surfactant or petroleum oil adjuvant and bentazon plus imazethapyr tank-mixes provided 85% or more control of common ragweed in 1991, and only imazethapyr at 71 g/ha plus 28% urea ammonium nitrate plus petroleum oil adjuvant or imazethapyr at 71 g/ha plus bentazon provided greater than 78% common ragweed control in 1992. Soybean yield was not different from the handweeded control only where bentazon plus 71 g/ha of imazethapyr or acifluorfen at 560 g/ha was applied.

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Effect of No-till Systems on Weed Control and Yields of Continuous Winter Wheat (Triticum aestivum)

Weed Science ◽

10.1017/s004317450007079x ◽

1983 ◽

Vol 31 (6) ◽

pp. 813-818 ◽

Cited By ~ 6

Author(s):

Charles L. Cleary ◽

Thomas F. Peeper

Keyword(s):

Triticum Aestivum ◽

Winter Wheat ◽

Weed Control ◽

Production Systems ◽

Conventional Tillage ◽

Yellow Nutsedge ◽

No Till ◽

Herbicide Treatments ◽

Winter Annual ◽

Annual Weeds

Experiments were conducted from 1979 to 1982 to determine whether selected herbicide treatments applied before or after harvest would provide adequate weed control without the use of tillage between crops in continuous winter wheat (Triticum aestivumL.) production systems. of the herbicide treatments evaluated, only oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) at 2.2 kg ai/ha applied prior to wheat maturity adequately controlled summer annual weeds each year. Populations of yellow nutsedge (Cyperus esculentusL. # CYPES) and/or clammy groundcherry (Physalis heterophyllaNees) increased from continued preharvest use of oryzalin in no-till treatments and were greater than those resulting from conventional tillage or various postharvest no-till treatments containing glyphosate [N-(phosphonomethyl)glycine]. After 4 yr, populations of winter annualCruciferaespp. at one location were lower in treatments that had poorer control of summer annual weeds or volunteer wheat. At a second location, winter annual broadleaf species were more numerous in conventionally tilled than in no-till treatments. Wheat yields obtained with no-till treatments were lower than yields obtained with conventional tillage in seasons favorable for high yields.

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Chemical weed control in winter wheat: Efficiency and economic return

Agricultural and Food Science ◽

10.23986/afsci.72014 ◽

1979 ◽

Vol 51 (1) ◽

pp. 521-527

Author(s):

Juhani Uoti ◽

Tuomo Juvankoski

Keyword(s):

Moisture Content ◽

Winter Wheat ◽

Weed Control ◽

Dry Weight ◽

Field Trials ◽

Average Yield ◽

Economic Return ◽

Producer Price ◽

Yield Increase ◽

Yield Level

In field trials in Vihti during the years 1968—1978 the average yield increase in winter wheat obtained with chemical Weed control was 439 kg/ha with a yield level of 3 704 kg/ha. The moisture content in percentages was 1.2 % lower in the sprayed plots than in the unsprayed plots. The number and the dry weight of weeds was greatly reduced by the spraying. The producer price for the wheat being at present 1 mk/kg, the value of the yield increase for the farmer is 439 mk/ha, whereas the decrease of the moisture content saves in drying costs 36 mk/ha. When the spraying costs estimated at 153 mk/ha have been deducted from these figures, the net return for the farmer is 322 mk/ha.

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Winter Wheat (Triticum aestivum) Yield Response to Winter Annual Broadleaf Weed Control

Weed Technology ◽

10.1017/s0890037x00023903 ◽

1995 ◽

Vol 9 (3) ◽

pp. 594-598 ◽

Cited By ~ 7

Author(s):

Robert C. Scott ◽

Thomas F. Peeper ◽

Jeffrey A. Koscelny

Keyword(s):

Correlation Analysis ◽

Winter Wheat ◽

Weed Control ◽

Wheat Yield ◽

Yield Response ◽

Wheat Grain ◽

Primary Target ◽

Herbicide Treatments ◽

Winter Wheat Yield ◽

Winter Annual

Selected herbicide treatments from 25 winter annual broadleaf weed control experiments conducted across Oklahoma from 1979 to 1993 were examined for winter wheat yield response to weed control. All experiments contained one or two of the same three weeds (henbit, bushy wallflower, or cutleaf eveningprimrose) as the primary target(s). Herbicide treatments included chlorsulfuron at 8.8 or 17.6 g ai/ha, and/or 2,4-D at 420 g ae/ha, all broadcast POST to wheat. Most herbicide treatments controlled the weeds, but increased wheat grain yield at only one site, wherein bushy wallflower density was 830/m2. Correlation analysis found no relationship between weed densities and wheat yield when chlorsulfuron at 8.8 g/ha was applied for henbit or moderate levels of bushy wallflower or cutleaf eveningprimrose. There was a significant positive relationship favoring spraying of bushy wallflower when the correlation analysis included data from one site with a density of 830 plants/m2.

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Pyroxsulam Compared with Competitive Standards for Efficacy in Winter Wheat

Weed Technology ◽

10.1614/wt-d-10-00055.1 ◽

2011 ◽

Vol 25 (3) ◽

pp. 316-321 ◽

Cited By ~ 7

Author(s):

Patrick W. Geier ◽

Phillip W. Stahlman ◽

Dallas E. Peterson ◽

Mark M. Claassen

Keyword(s):

Winter Wheat ◽

Weed Control ◽

Field Studies ◽

Downy Brome ◽

Application Timing ◽

Percentage Points ◽

Herbicide Treatment ◽

Herbicide Treatments ◽

Winter Annual ◽

Almost All

Field studies at six locations over 3 yr in Kansas compared pyroxsulam at two application timings to competitive standards for winter annual weed control in winter wheat. Pyroxsulam applied fall-POST (FP) controlled downy brome 84 to 99% and was similar to or greater than sulfosulfuron, propoxycarbazone, or propoxycarbazone plus mesosulfuron. Downy brome control was lower when application timing was delayed until spring (SP), such that no herbicide provided more than 90% downy brome control. Cheat control was 97% or more with almost all herbicides applied FP, and greater than 90% in most locations when herbicides were applied SP. Sulfosulfuron was the exception with only 30 to 81% cheat control. All FP-applied herbicides, except sulfosulfuron at Manhattan, KS, controlled blue mustard 95% or more. Pyroxsulam and propoxycarbazone plus mesosulfuron FP completely controlled henbit at Hesston, KS, in 2009, but no herbicide treatment provided more than 60% control when applied SP. Averaged over application timings, pyroxsulam provided the greatest henbit control (76 and 78%) at Manhattan and Hays, respectively, in 2009, and FP treatments were 33 and 28 percentage points more effective than SP treatments at those locations. Averaged over application timing, wheat yields did not differ between herbicide treatments in five of six locations. Averaged over herbicide treatment, FP-treated wheat yielded more grain than SP-treated wheat at three of the six locations.

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