Halosulfuron (35 g a.i. ha −1 ) applied preemergence (PRE), early-postemergence (EPOST), and late-postemergence (LPOST) does not adequately control volunteer adzuki bean in white bean, but halosulfuron applied EPOST and LPOST has the potential to be used for control of volunteer soybean in white bean.
Soltani, N., Shropshire, C. and Sikkema, P. H. 2012. Co-application of glyphosate plus an insecticide or fungicide in glyphosate-resistant soybean. Can. J. Plant Sci. 92: 297–302. Six field trials were conducted from 2008 to 2010 in Ontario to evaluate soybean injury and weed control efficacy with glyphosate tankmixed with various insecticides or fungicides. There was minimal visual injury (less than 4%) in glyphosate-resistant soybean and no adverse effect on soybean height and yield when cyhalothrin-lambda (Matador ® ), dimethoate (Lagon ® ), imidacloprid/deltamethrin (Concept ® ), spirotetramat (Movento ® ), pyraclostrobin (Headline ® ), azoxystrobin (Quadris ® ), propiconazole (Tilt ® ), azoxystrobin/propiconazole (Quilt ® ), tebuconazole (Folicur ® ) and trifloxystrobin/propiconazole (Stratego ® ) were tankmixed with glyphosate. Velvetleaf, pigweed species, common ragweed, common lambsquarters and green foxtail control ranged from 91–97, 94–99, 92–99, 80–94 and 98–100%, respectively. However, there was no adverse effect on velvetleaf, pigweed, common ragweed, common lambsquarters and green foxtail control, density and dry weight when one of the insecticides or fungicides evaluated was tankmixed with glyphosate. Based on these results, glyphosate tankmixed with cyhalothrin-lambda, dimethoate, imidacloprid/deltamethrin, spirotetramat, pyraclostrobin, azoxystrobin, propiconazole, azoxystrobin/propiconazole, tebuconazole or trifloxystrobin/propiconazole causes minimal crop injury and has no adverse effect on weed control in glyphosate-resistant soybean under Ontario environmental conditions.
Abstract Control of fall‐seeded annual ryegrass ( Lolium multiflorum Lam) cover crops with spring‐applied herbicides prior to seeding corn ( Zea mays L.) has been variable. Improved herbicide options are needed in order to increase the consistency of annual ryegrass termination prior to seeding corn. Four field experiments were conducted over a 2‐yr period (2018, 2019) in Ontario, Canada, to evaluate the control of fall‐seeded annual ryegrass cover crops with various corn herbicides, applied prior to seeding corn in the spring. Based on visual estimates, glyphosate alone controlled annual ryegrass 80% at 6 weeks after application (WAA). Acetolactate synthase (ALS) inhibitor herbicides, foramsulfuron, nicosulfuron, rimsulfuron, and nicosulfuron/rimsulfuron controlled annual ryegrass 82, 71, 88, and 88%, respectively, at 6 WAA. The tankmix of glyphosate with foramsulfuron, nicosulfuron, rimsulfuron, or nicosulfuron/rimsulfuron controlled annual ryegrass 94–98% at 6 WAA. Glyphosate reduced annual ryegrass density 73%; in contrast, foramsulfuron, nicosulfuron, rimsulfuron, and nicosulfuron/rimsulfuron did not reduce annual ryegrass density compared to the weedy control. The tankmix of glyphosate plus an ALS inhibitor herbicide reduced annual ryegrass density 88−94%. Reduced annual ryegrass interference with glyphosate applied alone resulted in an increase in corn yield of 86% compared to the control. Reduced annual ryegrass interference with foramsulfuron, nicosulfuron, rimsulfuron, and nicosulfuron/rimsulfuron applied alone resulted in an increase in corn yield 61, 61, 93, and 91%, and 98, 105, 95, and 98% when co‐applied with glyphosate, respectively. The tankmix of glyphosate with an ALS inhibitor herbicide resulted in excellent (>90%) annual ryegrass control and increased corn yield.
Abstract Six field experiments were established in southwestern Ontario in 2021 and 2022 to evaluate whether the addition of a grass herbicide (acetochlor, dimethenamid-p, flufenacet, pendimethalin, pyroxasulfone, or S -metolachlor) to tolpyralate + atrazine improves late-season weed control in corn. Tolpyralate + atrazine caused 12% and 5% corn injury at 1 and 4 wk after herbicide application (WAA); corn injury was not increased with the addition of a grass herbicide. Weed interference reduced corn yield 60%. The addition of a grass herbicide to tolpyralate + atrazine did not enhance velvetleaf control. The addition of acetochlor or dimethenamid-p to tolpyralate + atrazine enhanced pigweed species control 4% 4 WAA; the addition of other grass herbicides tested did not increase pigweed species control. The addition of acetochlor enhanced common ragweed control 5% at 4 WAA, and the addition of acetochlor or dimethenamid-p enhanced common ragweed control 8% at 8 WAA; the addition of other grass herbicides did not improve common ragweed control. The addition of acetochlor to tolpyralate + atrazine enhanced common lambsquarters control up to 4%; there was no enhancement in common lambsquarters control with the addition of the other grass herbicides. Tolpyralate + atrazine controlled barnyardgrass 90% and 78% at 4 and 8 WAA, respectively; the addition of a grass herbicide enhanced barnyardgrass control 9% to 10% and 21% at 4 and 8 WAA, respectively. Tolpyralate + atrazine controlled green or giant foxtail 80% and 69% at 4 and 8 WAA, respectively; the addition of a grass herbicide enhanced foxtail species control 15% to 19% and 24% to 29% at 4 and 8 WAA, respectively. This research shows that adding a grass herbicide to tolpyralate + atrazine mixture can improve weed control efficacy, especially increased annual grass control in corn production.
Abstract During 2016 and 2017, four field experiments were conducted at Huron Research Station near Exeter, ON, to evaluate the sensitivity of dry bean grown under a strip-tillage cropping system, to potential herbicides for the control of glyphosate-resistant (GR) horseweed. At 8 wk after emergence (WAE), saflufenacil, metribuzin, saflufenacil+metribuzin, 2,4-D ester, flumetsulam, cloransulam-methyl, and chlorimuron-ethyl caused 13% to 32%, 8% to 52%, 32% to 53%, 5% to 7%, 13% to 21%, 16% to 29%, and 23% to 43% visible injury in dry beans, respectively. Saflufenacil decreased aboveground biomass 65% in kidney bean and 80% in white bean. Metribuzin decreased biomass 82% in kidney bean and 50% in white bean. Saflufenacil+metribuzin decreased biomass 88% in kidney bean, 68% in small red bean, and 80% in white bean. Chlorimuron-ethyl decreased biomass 40% in white bean. There was no decrease in dry bean biomass with the other herbicides evaluated. Metribuzin and saflufenacil+metribuzin reduced kidney bean seed yield 72% and 76%, respectively. Saflufenacil+metribuzin, flumetsulam, cloransulam-methyl, and chlorimuron-ethyl reduced small red bean seed yield 39%, 27%, 30%, and 54%, respectively. Saflufenacil, metribuzin, saflufenacil+metribuzin, flumetsulam, cloransulam-methyl, and chlorimuron-ethyl reduced seed yield of white bean 52%, 32%, 62%, 33%, 42%, and 62%, respectively. There was no decrease in dry bean yield with the other herbicides evaluated. Among herbicides evaluated, 2,4-D ester caused the least crop injury with no effect in dry bean seed yield.
Three field experiments were completed over a three-year period (2019 to 2021) in Ontario, Canada to develop weed management programs in azuki bean with herbicides (pendimethalin, S-metolachlor, halosulfuron, and imazethapyr) applied alone and in combination, and metribuzin, applied preemergence (PRE). At 2 and 4 weeks after emergence (WAE), there was ≤ 8% azuki bean injury from the herbicide treatments evaluated, with the exception of the treatments that included S-metolachlor which caused up to 19% azuki bean injury. Pendimethalin (1080 g ai ha-1) and S-metolachlor (1600 g ai ha-1) controlled green foxtail 83-94% but provided poor control of common lambsquarters, wild mustard, redroot pigweed, common ragweed, and flower-of-an-hour. Imazethapyr (75 g ai ha-1) controlled common lambsquarters, wild mustard, redroot pigweed, and flower-of-an-hour 90-100% but provided 76-82% control of common ragweed and green foxtail. Halosulfuron (35 g ai ha-1) controlled wild mustard 100%, common ragweed 81-84%, common lambsquarters 77-83%, flower-of-an-hour 72-75%, redroot pigweed 59-72%, and green foxtail 19-23%. The tankmix of pendimethalin + S-metolachlor controlled green foxtail and common lambsquarters 87-97% but the control was only 23- 83% on wild mustard, redroot pigweed, common ragweed, and flower-of-an-hour. The tankmixes of pendimethalin + imazethapyr and pendimethalin + S-metolachlor + imazethapyr provided 90-100% control of common lambsquarters, wild mustard, redroot pigweed, flower-of-an-hour, and green foxtail, and 78-87% control of common ragweed. The tankmixes of pendimethalin + halosulfuron and pendimethalin + S-metolachlor + halosulfuron controlled common lambsquarters and wild mustard 91-100%, green foxtail 76-95%, flower-of-an-hour 70-94%, redroot pigweed 68-91%, and common ragweed 78-79%. Metribuzin (280 g ai ha-1) controlled common lambsquarters, wild mustard, redroot pigweed, common ragweed, flower-of-an-hour, and green foxtail up to 94, 98, 81, 58, 98, and 61% respectively; control improved to 99, 100, 97, 84, 99, and 83%, respectively when the rate was increased to 560 g ai ha-1. Generally, weed density and dry biomass reflected the level of weed control. Weed interference reduced azuki bean yield by 91% in this study. Generally, azuki bean yield reflected the level of weed control.
Abstract Tiafenacil is a new nonselective, protoporphyrinogen IX oxidase–inhibiting pyrimidinedione herbicide that is under consideration for registration to control grass and broadleaf weeds in corn, soybean, wheat, cotton, and other crops prior to crop emergence. The sensitivity of dry beans to tiafenacil is not known. Four field experiments were completed at Exeter and Ridgetown, ON, Canada, during the 2019 and 2020 growing seasons, to determine the sensitivity of azuki, kidney, small red, and white beans to tiafenacil applied preemergence (PRE) at 12.5, 25, 50, and 100 g ai ha −1 . Tiafenacil applied at 100 g ai ha −1 caused 5% or less injury to azuki, kidney, small red, and white beans: 0% to 3% injury to azuki bean; 1% to 5% injury to kidney bean; and 1% to 4% injury to both small red bean and white bean. Tiafenacil applied PRE at 12.5, 25, 50, and 100 g ai ha −1 caused up to 1%, 4%, 4%, and 5% visible dry bean injury, respectively, but had no negative effect on other measured growth parameters including seed yield. Crop injury was generally greatest when tiafenacil was appled at the 100 g ai ha −1 rate in dry beans. Generally, kidney, small red, and white bean were more sensitive to tiafenacil than azuki bean. Dry bean injury was persistent and increased with time with the greatest injury observed 8 wk after emergence. Tiafenacil applied PRE can be a useful addition to the current strategies to control grass and broadleaf weeds, especially glyphosate-resistant horseweed and amaranth species prior to bean emergence.
There is limited information on weed control with glyphosate plus mesotrione or saflufenacil when applied prior to seeding winter wheat in the autumn. A total of 12 field trials (six for each herbicide tankmix) were conducted over a three-year (2010-2012) at two locations (Ridgetown and Exeter, Ontario) to evaluate the effect of glyphosate plus mesotrione or saflufenacil at various rates for broadleaf weed control and red clover establishment in winter wheat. Glyphosate (900 g ae ha-1) and tankmixes of glyphosate (900 g ae ha-1) plus mesotrione or saflufenacil at 12.5, 25, 50, 75, 100, 150 and 200 g ai ha-1 applied preplant (PP) in the autumn resulted in minimal visible injury (0% - 2%) in the autumn and on May 1 and June 1 of the following spring in winter wheat. The PP application of glyphosate alone or in combination with mesotrione or saflufenacil provided only 1% - 30% control of common ragweed in the following spring. The PP application of glyphosate in combination with mesotrione or saflufenacil provided 74% - 100% control of wild mustard at 2 and 4 weeks after emergence (WAE) in autumn but the control was only 0% - 35% on June 1 of the following spring. Glyphosate plus mesotrione or saflufenacil did not have any effect on seed moisture content and yield of winter wheat compared to glyphosate alone. Clover establishment was reduced with glyphosate plus mesotrione at the two highest rates but was not affected with glyphosate plus saflufenacil compared to glyphosate alone. Based on these results, glyphosate alone and in combination with mesotrione or saflufenacil applied PP in the autumn at rates evaluated did not provide adequate residual control of common ragweed, common lambsquarters and wild mustard in the spring of the following year in winter wheat.
Field studies were conducted in 2009 and 2010 at the Huron Research Station, Exeter, Ontario and the University of Guelph Ridgetown Campus, Ridgetown, Ontario to determine the tolerance of four cultivars of cranberry bean (“Etna”, “Hooter”, “SVM Taylor”, and “Capri”) and four cultivars of kidney bean (“Red Hawk”, “Pink Panther”, “Calmont”, and “Majesty”) to linuron applied preemergence at 1125 and 2250 g·ai·ha-1. One week after emergence (WAE), linuron applied PRE caused 0.4% to 1.2% injury in “Etna”, “Hooter”, “SVM Tayler”, and “Capri” cranberry bean and 3.1% to 3.6% injury in “Red Hawk”, “Pink Panther”, “Calmont”, and “Majesty” kidney bean. At 2 and 4 WAE, there was no difference in injury among the dry bean cultivars. Contrast comparing injury due to linuron in cranberry vs kidney bean cultivars indicated 2.3%, 1.7%, and 1.2% greater injury in kidney bean compared to cranberry bean at 1, 2, and 4 WAE, respectively. Linuron PRE caused slightly greater injury in kidney bean compared to cranberry bean but crop injury was minimal with no adverse effect on plant height, shoot dry weight, seed moisture content, and yield under the environments evaluated. Based on this research, linuron applied PRE at the proposed rate of 1125 g·ai·ha-1 can be safely used in cranberry and kidney beans in Ontario.