Biologically-Effective-Dose of Tolpyralate and Tolpyralate plus Atrazine for Control of Multiple-Herbicide-Resistant Waterhemp [<i>Amaranthus tuberculatus</i>(Moq.) J. D. Sauer] in Corn  

作　　者：Christian Willemse Nader Soltani Brendan Metzger David C. Hooker Amit J. Jhala Darren E. Robinson Peter H. Sikkema Christian Willemse;Nader Soltani;Brendan Metzger;David C. Hooker;Amit J. Jhala;Darren E. Robinson;Peter H. Sikkema(Department of Plant Agriculture, University of Guelph, Ridgetown, ON, Canada;Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, USA)

机构地区：[1]Department of Plant Agriculture, University of Guelph, Ridgetown, ON, Canada [2]Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, USA

出　　处：《Agricultural Sciences》2021年第4期424-443,共20页农业科学（英文）

摘　　要：The biologically-effective-dose of tolpyralate, a new 4-hydroxyphenyl-pyruvate dioxygenase (HPPD)-inhibitor, applied alone or tank-mixed with atrazine, for the control of multiple-herbicide-resistant (MHR) waterhemp [<em>Amaranthus tuberculatus</em> (Moq.) J. D. Sauer] has not been studied in corn. Seven field experiments were conducted during a three-year period (2018, 2019, 2020) in Ontario, Canada with MHR waterhemp to determine: 1) the dose-response of MHR waterhemp to tolpyralate and tolpyralate plus atrazine, and 2) the relative efficacy of tolpyralate and tolpyralate plus atrazine to post-emergence corn herbicides, dicamba/atrazine (500/1000 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}) and mesotrione + atrazine (100 + 280 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}). Tolpyralate + atrazine (120 + 4000 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}) caused 13% corn injury at one site two weeks after application (WAA), which was observed as transient foliar chlorosis and bleaching of new leaves. At 12 WAA, the predicted dose of tolpyralate for 50% control of MHR waterhemp at Cottam and on Walpole Island was 8 and 2 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}, respectively;the predicted dose of tolpyralate + atrazine for 50% control of MHR waterhemp at Cottam and on Walpole Island was 5 + 160 and 1 + 21 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}, respectively. The difference in predicted dose at the two sites is likely due to differences in MHR density and resistance profile. Applied at the registered rate, tolpyralate (30 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}) and tolpyralate + atrazine (30 + 1000 g<span styleThe biologically-effective-dose of tolpyralate, a new 4-hydroxyphenyl-pyruvate dioxygenase (HPPD)-inhibitor, applied alone or tank-mixed with atrazine, for the control of multiple-herbicide-resistant (MHR) waterhemp [<em>Amaranthus tuberculatus</em> (Moq.) J. D. Sauer] has not been studied in corn. Seven field experiments were conducted during a three-year period (2018, 2019, 2020) in Ontario, Canada with MHR waterhemp to determine: 1) the dose-response of MHR waterhemp to tolpyralate and tolpyralate plus atrazine, and 2) the relative efficacy of tolpyralate and tolpyralate plus atrazine to post-emergence corn herbicides, dicamba/atrazine (500/1000 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}) and mesotrione + atrazine (100 + 280 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}). Tolpyralate + atrazine (120 + 4000 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}) caused 13% corn injury at one site two weeks after application (WAA), which was observed as transient foliar chlorosis and bleaching of new leaves. At 12 WAA, the predicted dose of tolpyralate for 50% control of MHR waterhemp at Cottam and on Walpole Island was 8 and 2 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}, respectively;the predicted dose of tolpyralate + atrazine for 50% control of MHR waterhemp at Cottam and on Walpole Island was 5 + 160 and 1 + 21 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}, respectively. The difference in predicted dose at the two sites is likely due to differences in MHR density and resistance profile. Applied at the registered rate, tolpyralate (30 g<span style="white-space:nowrap;">&#183;</span>ha^{<span style="white-space:nowrap;">&#8722;</span>1}) and tolpyralate + atrazine (30 + 1000 g<span style

关 键 词：Biological Effective Dose Biomass Density Multiple-Herbicide-Resistant Weed Management 

分 类 号：X59[环境科学与工程—环境工程]