Effect of Growth Stage on Glyphosate-Tolerant Soybean Sensitivity to Micro-Rates of 2,4-D
Апстракт
Off-target movement of 2,4-D can cause severe injury to susceptible crops including non-2,4-D-tolerant crops. A field study was conducted in 2019 near Concord, NE to investigate the effect of growth stage on glyphosate-tolerant (GT) soybean sensitivity to micro-rates of 2,4-D. The experiment used a randomized complete block design (RCBD) with eight replications and a split-plot arrangement. Main plots consisted of three 2,4-D application times [second trifoliate (V2); beginning of flowering (V7/R1); and full flowering (R2)] and subplots consisted of six micro rates of 2,4-D (1/5; 1/10; 1/50; 1/100; 1/500; and 1/1000 of the label recommended dose of 1,120 g ae ha-1) and a check with no herbicide applied. Soybean injury assessment and plant height measurements were performed at 7, 14 and 21 days after treatment (DAT). Number of days to canopy closure was also recorded. In general, increase in 2,4-D dose increased soybean injury and reduced plant height. Less than 1/10 of the label recomm...ended dose of 2,4-D caused 5-20% injury to GT soybean regardless of application time; however, GT soybean was more sensitive to 2,4-D injury at R2 than the V2 and R1 stages. A 2,4-D dose of 44.88 g ae ha-1 caused 5% injury to GT soybean at the R2 stage compared with a 1.4- and 1.2-fold higher dose required to cause the same level of injury at the V2 and R1 stage, respectively. Plant height, on the other hand, was more sensitive to 2,4-D at R1 than the V2 and R2 stages. A dose of 2,4-D of 6.93 g ae ha-1 reduced plant height at R1 by 5% (3.7 cm) compared with a 1.5 (10.29 g ae ha-1) to 1.6 (11.22 g ae ha-1)-fold higher dose that was required to cause the same reduction in plant height at other growth stages. Because of this increase in GT soybean injury and reduction in plant height, there was a delay in canopy closure with a 2,4-D dose of 9.76, 3.53 and 3.81 g ae ha-1 resulting in a 5 day delay in canopy closure at V2, R1 and R2 stage, respectively. Altogether, these results show that GT soybean is sensitive to micro-rates of 2,4-D especially at the reproductive stages.
Кључне речи:
2,4-D-tolerant cropsИзвор:
Proceedings of the 74th Annual Meeting of the North Central Weed Science Society, December 10-13, 2019 Columbus, OH, 2019, 36-Издавач:
- North Central Weed Science Society (NCWSS)
Институција/група
Institut za povrtarstvoTY - CONF AU - Cuvaca, Ivan AU - Scott, Jon AU - Jovanović, Darko AU - Knežević, Stevan PY - 2019 UR - http://RIVeC.institut-palanka.rs/handle/123456789/833 AB - Off-target movement of 2,4-D can cause severe injury to susceptible crops including non-2,4-D-tolerant crops. A field study was conducted in 2019 near Concord, NE to investigate the effect of growth stage on glyphosate-tolerant (GT) soybean sensitivity to micro-rates of 2,4-D. The experiment used a randomized complete block design (RCBD) with eight replications and a split-plot arrangement. Main plots consisted of three 2,4-D application times [second trifoliate (V2); beginning of flowering (V7/R1); and full flowering (R2)] and subplots consisted of six micro rates of 2,4-D (1/5; 1/10; 1/50; 1/100; 1/500; and 1/1000 of the label recommended dose of 1,120 g ae ha-1) and a check with no herbicide applied. Soybean injury assessment and plant height measurements were performed at 7, 14 and 21 days after treatment (DAT). Number of days to canopy closure was also recorded. In general, increase in 2,4-D dose increased soybean injury and reduced plant height. Less than 1/10 of the label recommended dose of 2,4-D caused 5-20% injury to GT soybean regardless of application time; however, GT soybean was more sensitive to 2,4-D injury at R2 than the V2 and R1 stages. A 2,4-D dose of 44.88 g ae ha-1 caused 5% injury to GT soybean at the R2 stage compared with a 1.4- and 1.2-fold higher dose required to cause the same level of injury at the V2 and R1 stage, respectively. Plant height, on the other hand, was more sensitive to 2,4-D at R1 than the V2 and R2 stages. A dose of 2,4-D of 6.93 g ae ha-1 reduced plant height at R1 by 5% (3.7 cm) compared with a 1.5 (10.29 g ae ha-1) to 1.6 (11.22 g ae ha-1)-fold higher dose that was required to cause the same reduction in plant height at other growth stages. Because of this increase in GT soybean injury and reduction in plant height, there was a delay in canopy closure with a 2,4-D dose of 9.76, 3.53 and 3.81 g ae ha-1 resulting in a 5 day delay in canopy closure at V2, R1 and R2 stage, respectively. Altogether, these results show that GT soybean is sensitive to micro-rates of 2,4-D especially at the reproductive stages. PB - North Central Weed Science Society (NCWSS) C3 - Proceedings of the 74th Annual Meeting of the North Central Weed Science Society, December 10-13, 2019 Columbus, OH T1 - Effect of Growth Stage on Glyphosate-Tolerant Soybean Sensitivity to Micro-Rates of 2,4-D SP - 36 UR - https://hdl.handle.net/21.15107/rcub_rivec_833 ER -
@conference{ author = "Cuvaca, Ivan and Scott, Jon and Jovanović, Darko and Knežević, Stevan", year = "2019", abstract = "Off-target movement of 2,4-D can cause severe injury to susceptible crops including non-2,4-D-tolerant crops. A field study was conducted in 2019 near Concord, NE to investigate the effect of growth stage on glyphosate-tolerant (GT) soybean sensitivity to micro-rates of 2,4-D. The experiment used a randomized complete block design (RCBD) with eight replications and a split-plot arrangement. Main plots consisted of three 2,4-D application times [second trifoliate (V2); beginning of flowering (V7/R1); and full flowering (R2)] and subplots consisted of six micro rates of 2,4-D (1/5; 1/10; 1/50; 1/100; 1/500; and 1/1000 of the label recommended dose of 1,120 g ae ha-1) and a check with no herbicide applied. Soybean injury assessment and plant height measurements were performed at 7, 14 and 21 days after treatment (DAT). Number of days to canopy closure was also recorded. In general, increase in 2,4-D dose increased soybean injury and reduced plant height. Less than 1/10 of the label recommended dose of 2,4-D caused 5-20% injury to GT soybean regardless of application time; however, GT soybean was more sensitive to 2,4-D injury at R2 than the V2 and R1 stages. A 2,4-D dose of 44.88 g ae ha-1 caused 5% injury to GT soybean at the R2 stage compared with a 1.4- and 1.2-fold higher dose required to cause the same level of injury at the V2 and R1 stage, respectively. Plant height, on the other hand, was more sensitive to 2,4-D at R1 than the V2 and R2 stages. A dose of 2,4-D of 6.93 g ae ha-1 reduced plant height at R1 by 5% (3.7 cm) compared with a 1.5 (10.29 g ae ha-1) to 1.6 (11.22 g ae ha-1)-fold higher dose that was required to cause the same reduction in plant height at other growth stages. Because of this increase in GT soybean injury and reduction in plant height, there was a delay in canopy closure with a 2,4-D dose of 9.76, 3.53 and 3.81 g ae ha-1 resulting in a 5 day delay in canopy closure at V2, R1 and R2 stage, respectively. Altogether, these results show that GT soybean is sensitive to micro-rates of 2,4-D especially at the reproductive stages.", publisher = "North Central Weed Science Society (NCWSS)", journal = "Proceedings of the 74th Annual Meeting of the North Central Weed Science Society, December 10-13, 2019 Columbus, OH", title = "Effect of Growth Stage on Glyphosate-Tolerant Soybean Sensitivity to Micro-Rates of 2,4-D", pages = "36", url = "https://hdl.handle.net/21.15107/rcub_rivec_833" }
Cuvaca, I., Scott, J., Jovanović, D.,& Knežević, S.. (2019). Effect of Growth Stage on Glyphosate-Tolerant Soybean Sensitivity to Micro-Rates of 2,4-D. in Proceedings of the 74th Annual Meeting of the North Central Weed Science Society, December 10-13, 2019 Columbus, OH North Central Weed Science Society (NCWSS)., 36. https://hdl.handle.net/21.15107/rcub_rivec_833
Cuvaca I, Scott J, Jovanović D, Knežević S. Effect of Growth Stage on Glyphosate-Tolerant Soybean Sensitivity to Micro-Rates of 2,4-D. in Proceedings of the 74th Annual Meeting of the North Central Weed Science Society, December 10-13, 2019 Columbus, OH. 2019;:36. https://hdl.handle.net/21.15107/rcub_rivec_833 .
Cuvaca, Ivan, Scott, Jon, Jovanović, Darko, Knežević, Stevan, "Effect of Growth Stage on Glyphosate-Tolerant Soybean Sensitivity to Micro-Rates of 2,4-D" in Proceedings of the 74th Annual Meeting of the North Central Weed Science Society, December 10-13, 2019 Columbus, OH (2019):36, https://hdl.handle.net/21.15107/rcub_rivec_833 .