A preliminary study conducted in the central USA near Colby and Hays, Kansas (KS) in 2010 indicated a premix of S-metolachlor & sulfentrazone codenamed F7583 (Broadaxe?) had good potential for use in sunflower (He...A preliminary study conducted in the central USA near Colby and Hays, Kansas (KS) in 2010 indicated a premix of S-metolachlor & sulfentrazone codenamed F7583 (Broadaxe?) had good potential for use in sunflower (Helianthus annuus L.). Additional studies were conducted in 2011 at Colby, Hays, Manhattan, KS to refine rate and application timing of F7583 for weed control and crop safety. Four rates of F7583 (860, 1100, 1350 and 1840 g·ha-1) were compared to single rates of S-metolachlor and pendimethalin, and applied 21 days preplant versus preemergence (PRE). F7583 at ≥1100 g·ha-1 applied preplant or PRE controlled Palmer amaranth (Amaranthus palmeri S. Wats.) and kochia [Kochia scoparia (L.) Schrad.] ≥95% and 100%, respectively in neutral pH soils. In slightly acidic soils, PRE application of F7583 was more effective against Palmer amaranth and grass weeds compared to preplant application. No benefit was gained by increasing the rate of F7583 from 1100 to 1350 g·ha-1 at either application timing. Puncturevine (Tribulus terrestris L.) control was not commercially satisfactory with F7583 at any rate or time of application. Both S-metolachlor at 1070 g·ha-1 and pendimethalin at 1600 g·ha-1 applied either preplant or PRE were considerably less effective on all three broadleaf weeds compared to F7583 treatments. Individually, S-metolachlor and pendimethalin were more effective when applied PRE compared to preplant application. F7583 did not reduce sunflower plant population or visibly injure sunflower anytime during the season.展开更多
A field study was conducted at two locations in Kansas, USA in 2011 and 2012 to test weed control efficacy and crop response to preemergence-applied pyroxasulfone alone and in combination with sulfentrazone in sunflow...A field study was conducted at two locations in Kansas, USA in 2011 and 2012 to test weed control efficacy and crop response to preemergence-applied pyroxasulfone alone and in combination with sulfentrazone in sunflower. Treatments included three rates of pyroxasulfone (100, 200 and 400 g·ha-1) applied alone and tank-mixed with sulfentrazone at 70, 140 and 280 g·ha-1. Commercial standards sulfentrazone at 140 g·ha-1 + pendimethalin at 1390 g·ha-1 and sulfentrazone at 140 g·ha-1 + S-metolachlor at 1280 g·ha-1 were also included. Pyroxasulfone at 100 g·ha-1 controlled Palmer amaranth 87% at 3 weeks after application (WAA), but control decreased to 76% at 6 WAA. Increasing pyroxasulfone rate to ≥200 g·ha-1 or tank mixing with sulfentazone at 140 g·ha-1 provided ≥90% Palmer amaranth control for at least 6 WAA. Sulfentrazone alone at 70 g·ha-1 controlled Palmer amaranth 77% at 3 WAA, but control dropped to 69% at 6 WAA. Increasing sulfentrazone rate from 70 to 140 or 280 g·ha-1 increased control to >90% at 3 WAA, but did not maintain acceptable control at 6 WAA. Tank mixing sulfentrazone at 140 g·ha-1 with pendimethalin at 1390 g·ha-1 or S-metolachlor at 1280 g·ha-1 controlled Palmer amaranth ≥90 and 84% at 3 WAA and 6 WAA, respectively. The lowest rate of pyroxasulfone (100 g·ha-1) controlled kochia 98% and the control was complete with all other treatments. However, no treatment provided as much as 90% puncturevine control at 3 WAA and the control was commercially unacceptable (<75%) at 6 WAA. No treatment visibly injured sunflower anytime during the season or reduced sunflower plant population.展开更多
Eight field trials (<span style="font-family:Verdana;">2 in 2016, 3 in 2017, 3 in 2018) </span><span style="font-family:Verdana;">were conducted</span><span style="f...Eight field trials (<span style="font-family:Verdana;">2 in 2016, 3 in 2017, 3 in 2018) </span><span style="font-family:Verdana;">were conducted</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> in farmers’ fields with heavy infestations of GR </span><i><span style="font-family:Verdana;">Conyza</span></i><span style="font-family:Verdana;"> <i>canadensis</i></span><span style="font-family:Verdana;"> (Canada fleabane, horseweed or </span><span style="font-family:Verdana;">marestail</span><span style="font-family:Verdana;">) </span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">to evaluate glyphosate (900 g ae ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) plus </span><span style="font-family:Verdana;">saflufenacil</span><span style="font-family:Verdana;"> (25 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), 2,4-D ester (500 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) or paraquat (1100 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) applied </span><span style="font-family:Verdana;">preplant</span><span style="font-family:Verdana;"> (PP) as 2-way </span><span style="font-family:Verdana;">tankmixes</span><span style="font-family:Verdana;">, or in 3-way </span><span style="font-family:Verdana;">tankmixes</span><span style="font-family:Verdana;"> with sulfentrazone (140 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), flumioxazin (107 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) or metribuzin (400 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">)</span><span><span style="font-family:Verdana;"> for the glyphosate-resistant (GR) </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> control in GR soybean. </span></span><span><span style="font-family:Verdana;">Glyphosate plus </span><span style="font-family:Verdana;">saflufenacil</span><span style="font-family:Verdana;"> applied PP controlled GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> as much as 90%. The addition of sulfentrazone, flumioxazin </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> metribuzin to the </span><span style="font-family:Verdana;">tankmix</span><span style="font-family:Verdana;"> provided as much as 93%, 96% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 97% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">, respectively. Glyphosate plus 2,4-D ester applied PP provided as much as 59% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">. The addition of sulfentrazone, flumioxazin </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> metribuzin to the </span><span style="font-family:Verdana;">tankmix</span><span style="font-family:Verdana;"> provided as much as 60%, 5</span></span><span><span style="font-family:Verdana;">9% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 91% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">, respectively. Glyphosate plus paraquat applied PP provided as much as 85% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">. The addition of sulfentrazone, flumioxazin </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> metribuzin to the </span><span style="font-family:Verdana;">tankmix</span><span style="font-family:Verdana;"> provided as much as 88%, 89% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 98% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">, respectively. Density and biomass reductions of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> with herbicides evaluated followed the same pattern as weed control evaluations. </span><span><span style="font-family:Verdana;">GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> interference reduced soybean yield 66%. Reduced GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> interference with the </span><span style="font-family:Verdana;">preplant</span><span style="font-family:Verdana;"> herbicides evaluated provided soybean yield similar to the</span></span></span><span><span><span style="font-family:Verdana;"> weed-free control. Results from this study </span><span style="font-family:Verdana;">show</span><span style="font-family:Verdana;"> that glyphosate plus </span><span style="font-family:Verdana;">saflufenacil</span><span style="font-family:Verdana;">, glyphosate plus 2,4-D ester </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> glyphosate plus paraquat </span><span style="font-family:Verdana;">tankmixed</span><span style="font-family:Verdana;"> with metribuzin can provide effective control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> in GR soybean.</span></span></span></span>展开更多
Nine field experiments were conducted in 2011 and 2012 at various locations in southern Ontario, Canada to determine the tolerance of soybean (Glycine max (L.) Merr.) to herbicides inhibiting protoporphyrinogen oxidas...Nine field experiments were conducted in 2011 and 2012 at various locations in southern Ontario, Canada to determine the tolerance of soybean (Glycine max (L.) Merr.) to herbicides inhibiting protoporphyrinogen oxidase (Protox) and very long chain fatty acid (VLCFA) synthesis applied alone and in combination. Preemergence applications were evaluated for soybean injury, plant height, shoot dry weight, and yield in the absence of weed competition. Early-season soybean injury from the Protox inhibitors persisted 4 weeks after soybean emergence (WAE) with 3%, 5%, and 18% injury for flumioxazin, saflufenacil, and sulfentrazone, respectively. When Protox inhibitors were tank mixed with VLCFA inhibitors (i.e., dimethenamid-P, S-metolachlor, and pyroxasulfone), additive interactions were observed for injury with saflufenacil and sulfentrazone;whereas synergistic interactions were observed with flumioxazin. However, injury subsided over time decreasing from as much as 34% injury 1 WAE for the flumioxazin + S-metolachlor tank mix down to 9% injury 4 WAE. In general, when saflufenacil or flumioxazin were tank mixed with VLCFA inhibitors, greater than expected reductions in height and dry weight were observed indicating synergistic responses;while no interactive effects were detected with sulfentrazone and VLCFA inhibitor tank mixes. For the flumioxazin tank mixes that contained dimethenamid-P or S-metolachlor, the reduction in yield was greater than expected indicating synergistic interactive effects. Yet, all the demonstrated impacts were transient as the yield for soybean treated with any of the Protox inhibitor and VLCFA inhibitor tank mixes tested were similar to the untreated control. Therefore, usage restriction on these mixtures, based on perceived negative yield impact, should be lifted so the herbicides could be combined to expand weed control options.展开更多
文摘A preliminary study conducted in the central USA near Colby and Hays, Kansas (KS) in 2010 indicated a premix of S-metolachlor & sulfentrazone codenamed F7583 (Broadaxe?) had good potential for use in sunflower (Helianthus annuus L.). Additional studies were conducted in 2011 at Colby, Hays, Manhattan, KS to refine rate and application timing of F7583 for weed control and crop safety. Four rates of F7583 (860, 1100, 1350 and 1840 g·ha-1) were compared to single rates of S-metolachlor and pendimethalin, and applied 21 days preplant versus preemergence (PRE). F7583 at ≥1100 g·ha-1 applied preplant or PRE controlled Palmer amaranth (Amaranthus palmeri S. Wats.) and kochia [Kochia scoparia (L.) Schrad.] ≥95% and 100%, respectively in neutral pH soils. In slightly acidic soils, PRE application of F7583 was more effective against Palmer amaranth and grass weeds compared to preplant application. No benefit was gained by increasing the rate of F7583 from 1100 to 1350 g·ha-1 at either application timing. Puncturevine (Tribulus terrestris L.) control was not commercially satisfactory with F7583 at any rate or time of application. Both S-metolachlor at 1070 g·ha-1 and pendimethalin at 1600 g·ha-1 applied either preplant or PRE were considerably less effective on all three broadleaf weeds compared to F7583 treatments. Individually, S-metolachlor and pendimethalin were more effective when applied PRE compared to preplant application. F7583 did not reduce sunflower plant population or visibly injure sunflower anytime during the season.
文摘A field study was conducted at two locations in Kansas, USA in 2011 and 2012 to test weed control efficacy and crop response to preemergence-applied pyroxasulfone alone and in combination with sulfentrazone in sunflower. Treatments included three rates of pyroxasulfone (100, 200 and 400 g·ha-1) applied alone and tank-mixed with sulfentrazone at 70, 140 and 280 g·ha-1. Commercial standards sulfentrazone at 140 g·ha-1 + pendimethalin at 1390 g·ha-1 and sulfentrazone at 140 g·ha-1 + S-metolachlor at 1280 g·ha-1 were also included. Pyroxasulfone at 100 g·ha-1 controlled Palmer amaranth 87% at 3 weeks after application (WAA), but control decreased to 76% at 6 WAA. Increasing pyroxasulfone rate to ≥200 g·ha-1 or tank mixing with sulfentazone at 140 g·ha-1 provided ≥90% Palmer amaranth control for at least 6 WAA. Sulfentrazone alone at 70 g·ha-1 controlled Palmer amaranth 77% at 3 WAA, but control dropped to 69% at 6 WAA. Increasing sulfentrazone rate from 70 to 140 or 280 g·ha-1 increased control to >90% at 3 WAA, but did not maintain acceptable control at 6 WAA. Tank mixing sulfentrazone at 140 g·ha-1 with pendimethalin at 1390 g·ha-1 or S-metolachlor at 1280 g·ha-1 controlled Palmer amaranth ≥90 and 84% at 3 WAA and 6 WAA, respectively. The lowest rate of pyroxasulfone (100 g·ha-1) controlled kochia 98% and the control was complete with all other treatments. However, no treatment provided as much as 90% puncturevine control at 3 WAA and the control was commercially unacceptable (<75%) at 6 WAA. No treatment visibly injured sunflower anytime during the season or reduced sunflower plant population.
文摘Eight field trials (<span style="font-family:Verdana;">2 in 2016, 3 in 2017, 3 in 2018) </span><span style="font-family:Verdana;">were conducted</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> in farmers’ fields with heavy infestations of GR </span><i><span style="font-family:Verdana;">Conyza</span></i><span style="font-family:Verdana;"> <i>canadensis</i></span><span style="font-family:Verdana;"> (Canada fleabane, horseweed or </span><span style="font-family:Verdana;">marestail</span><span style="font-family:Verdana;">) </span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">to evaluate glyphosate (900 g ae ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) plus </span><span style="font-family:Verdana;">saflufenacil</span><span style="font-family:Verdana;"> (25 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), 2,4-D ester (500 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) or paraquat (1100 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) applied </span><span style="font-family:Verdana;">preplant</span><span style="font-family:Verdana;"> (PP) as 2-way </span><span style="font-family:Verdana;">tankmixes</span><span style="font-family:Verdana;">, or in 3-way </span><span style="font-family:Verdana;">tankmixes</span><span style="font-family:Verdana;"> with sulfentrazone (140 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), flumioxazin (107 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) or metribuzin (400 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">)</span><span><span style="font-family:Verdana;"> for the glyphosate-resistant (GR) </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> control in GR soybean. </span></span><span><span style="font-family:Verdana;">Glyphosate plus </span><span style="font-family:Verdana;">saflufenacil</span><span style="font-family:Verdana;"> applied PP controlled GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> as much as 90%. The addition of sulfentrazone, flumioxazin </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> metribuzin to the </span><span style="font-family:Verdana;">tankmix</span><span style="font-family:Verdana;"> provided as much as 93%, 96% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 97% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">, respectively. Glyphosate plus 2,4-D ester applied PP provided as much as 59% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">. The addition of sulfentrazone, flumioxazin </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> metribuzin to the </span><span style="font-family:Verdana;">tankmix</span><span style="font-family:Verdana;"> provided as much as 60%, 5</span></span><span><span style="font-family:Verdana;">9% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 91% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">, respectively. Glyphosate plus paraquat applied PP provided as much as 85% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">. The addition of sulfentrazone, flumioxazin </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> metribuzin to the </span><span style="font-family:Verdana;">tankmix</span><span style="font-family:Verdana;"> provided as much as 88%, 89% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 98% control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;">, respectively. Density and biomass reductions of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> with herbicides evaluated followed the same pattern as weed control evaluations. </span><span><span style="font-family:Verdana;">GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> interference reduced soybean yield 66%. Reduced GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> interference with the </span><span style="font-family:Verdana;">preplant</span><span style="font-family:Verdana;"> herbicides evaluated provided soybean yield similar to the</span></span></span><span><span><span style="font-family:Verdana;"> weed-free control. Results from this study </span><span style="font-family:Verdana;">show</span><span style="font-family:Verdana;"> that glyphosate plus </span><span style="font-family:Verdana;">saflufenacil</span><span style="font-family:Verdana;">, glyphosate plus 2,4-D ester </span><span style="font-family:Verdana;">or</span><span style="font-family:Verdana;"> glyphosate plus paraquat </span><span style="font-family:Verdana;">tankmixed</span><span style="font-family:Verdana;"> with metribuzin can provide effective control of GR </span><i><span style="font-family:Verdana;">C.</span></i><span style="font-family:Verdana;"> <i><span style="font-family:Verdana;">canadensis</span></i></span><span style="font-family:Verdana;"> in GR soybean.</span></span></span></span>
文摘Nine field experiments were conducted in 2011 and 2012 at various locations in southern Ontario, Canada to determine the tolerance of soybean (Glycine max (L.) Merr.) to herbicides inhibiting protoporphyrinogen oxidase (Protox) and very long chain fatty acid (VLCFA) synthesis applied alone and in combination. Preemergence applications were evaluated for soybean injury, plant height, shoot dry weight, and yield in the absence of weed competition. Early-season soybean injury from the Protox inhibitors persisted 4 weeks after soybean emergence (WAE) with 3%, 5%, and 18% injury for flumioxazin, saflufenacil, and sulfentrazone, respectively. When Protox inhibitors were tank mixed with VLCFA inhibitors (i.e., dimethenamid-P, S-metolachlor, and pyroxasulfone), additive interactions were observed for injury with saflufenacil and sulfentrazone;whereas synergistic interactions were observed with flumioxazin. However, injury subsided over time decreasing from as much as 34% injury 1 WAE for the flumioxazin + S-metolachlor tank mix down to 9% injury 4 WAE. In general, when saflufenacil or flumioxazin were tank mixed with VLCFA inhibitors, greater than expected reductions in height and dry weight were observed indicating synergistic responses;while no interactive effects were detected with sulfentrazone and VLCFA inhibitor tank mixes. For the flumioxazin tank mixes that contained dimethenamid-P or S-metolachlor, the reduction in yield was greater than expected indicating synergistic interactive effects. Yet, all the demonstrated impacts were transient as the yield for soybean treated with any of the Protox inhibitor and VLCFA inhibitor tank mixes tested were similar to the untreated control. Therefore, usage restriction on these mixtures, based on perceived negative yield impact, should be lifted so the herbicides could be combined to expand weed control options.
