Management options are needed to limit sweetpotato yield loss due to weeds. Greenhouse studies were conducted in 2018 in Greensboro, NC, and in the field from 2016 to 2018 in Clinton, NC, to evaluate the effect of bicyclopyrone on sweetpotato and Palmer amaranth (field only). In greenhouse studies, Covington and NC04-531 clones were treated with bicyclopyrone (0, 25, 50, 100, or 150 g ai ha−1) either preplant (PP; i.e., immediately before transplanting) or post-transplant (PT; i.e., on the same day after transplanting). Sweetpotato plant injury and stunting increased, and vine length and shoot dry weight decreased with increasing rate of bicyclopyrone regardless of clone or application timing. In field studies, Beauregard (2016) or Covington (2017 and 2018) sweetpotato clones were treated with bicyclopyrone at 50 g ha−1 PP, flumioxazin at 107 g ai ha−1 PP, bicyclopyrone at 50 or 100 g ha−1 PP followed by (fb) S-metolachlor at 800 g ai ha−1 PT, flumioxazin at 107 g ha−1 PP fb S-metolachlor at 800 g ha−1 PT, flumioxazin at 107 g ha−1 PP fb S-metolachlor at 800 g ha−1 PT fb bicyclopyrone at 50 g ha−1 PT-directed, and clomazone at 420 g ai ha−1 PP fb S-metolachlor at 800 g ha−1 PT. Bicyclopyrone PP at 100 g ha−1 fb S-metolachlor PT caused 33% or greater crop stunting and 44% or greater marketable yield reduction compared with the weed-free check in 2016 (Beauregard) and 2017 (Covington). Bicyclopyrone PP at 50 g ha−1 alone or fb S-metolachlor PT resulted in 12% or less injury and similar no. 1 and jumbo yields as the weed-free check in 2 of 3 yr. Injury to Covington from bicyclopyrone PT-directed was 4% or less at 4 or 5 wk after transplanting and marketable yield was similar to that of the weed-free check in 2017 and 2018.

中文翻译：

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双环吡喃酮除草剂对甘薯和棕榈苋（Amaranthus palmeri）的影响

需要采取管理措施来限制杂草造成的甘薯产量损失。温室研究于 2018 年在北卡罗来纳州格林斯伯勒和 2016 年至 2018 年在北卡罗来纳州克林顿的田间进行，以评估双环吡喃酮对甘薯和苋菜的影响（仅限田间）。在温室研究中，Covington 和 NC04-531 克隆用双环吡喃酮（0、25、50、100 或 150 g ai ha-1) 种植前（PP；即移植前）或移植后（PT；即移植后同一天）。无论克隆或施用时机如何，甘薯植株损伤和发育迟缓增加，藤蔓长度和茎干重随着双环吡喃酮用量的增加而降低。在田间研究中，Beauregard (2016) 或 Covington (2017 和 2018) 用 50 g ha 的双环吡喃酮处理甘薯克隆-1PP，氟咪嗪，107 g ai ha-1PP，双环吡喃酮，50 或 100 g ha-1PP 后跟 (fb)小号-异丙甲草胺，800 g ai ha-1PT，氟咪嗪，107 g ha-1PP FB小号-异丙甲草胺，800 g ha-1PT，氟咪嗪，107 g ha-1PP FB小号-异丙甲草胺，800 g ha-1PT fb 双环吡喃酮，50 g ha-1PT 导向和 420 g ai ha 的异恶草酮-1PP FB小号-异丙甲草胺，800 g ha-1PT。双环吡喃酮 PP 100 g ha-1脸书S-与 2016 年（Beauregard）和 2017 年（Covington）的无杂草检查相比，异丙甲草胺 PT 导致 33% 或更多的作物发育迟缓和 44% 或更多的商品减产。双环吡喃酮 PP 50 g ha-1单独或fbS-异丙甲草胺 PT 导致 12% 或更少的伤害和类似的没有。1 和巨型产量作为 3 年中的 2 年的无杂草检查。在移栽后 4 或 5 周，双环吡喃酮 PT 对 Covington 的伤害为 4% 或更少，可销售产量与 2017 年和 2018 年的无杂草检查相似。