Feral rye (Secale cereale L.) is one of the most troublesome winter annual grass weed species in semi‐arid winter wheat (Triticum aestivum L.) production systems across the central Great Plains (CGP). Lack of effective herbicide options further complicates the selective control of feral rye in winter wheat. The main objectives of this research were: (a) determine the sensitivity response of 10 feral rye populations collected from Kansas wheat fields to quizalofop‐p‐ethyl in a dose‐response assay, and (b) to determine the effectiveness of various rates and application timings (fall or spring) of quizalofop‐p‐ethyl for feral rye control in quizalofop‐resistant winter wheat in the CGP. Dose‐response assays indicated that all tested feral rye populations were highly sensitive to quizalofop‐p‐ethyl with GR₉₀ values (doses of quizalofop‐p‐ethyl needed for 90% reductions in shoot biomass at 3 wk after treatment) ranging from 33 to 72 g a.i. ha⁻¹. A field study conducted in Colorado, Kansas, and Oklahoma for a total of 5 site‐years indicated that quizalofop‐p‐ethyl applied at ≥77 g a.i. ha⁻¹ in the fall or spring provided season‐long feral rye control at 92–100% in quizalofop‐resistant winter wheat. Irrespective of tested rates and application timings, a quizalofop‐p‐ethyl treatment protected winter wheat yield loss of 17–27% due to reduced feral rye competition compared to the nontreated weedy check in Colorado and Oklahoma. Results suggested that quizalofop‐p‐ethyl at labelled use rates (77–92 g a.i. ha⁻¹) applied in fall or spring can provide effective feral rye control in quizalofop‐resistant winter wheat.

中文翻译：

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大平原中部抗quizalofopop小麦的野生黑麦控制

野生黑麦（Secale graine L.）是半干旱冬小麦（Triticum aestivum）中最麻烦的冬季一年生禾本科杂草物种之一L.）遍布大平原中部（CGP）的生产系统。缺乏有效的除草剂选择还使冬小麦中选择性控制黑麦变得更加复杂。这项研究的主要目的是：（a）在剂量反应测定法中确定从堪萨斯州小麦田采集的10种野生黑麦种群对喹唑啉磷的敏感性响应，以及（b）确定各种速率和剂量的有效性。在CGP中，将基扎洛普-对-乙基在抗基扎洛普的冬小麦中控制黑麦的应用时间（秋季或春季）。剂量反应分析表明，所有测试的黑麦种群对quizalofop-p-乙基高度敏感，其GR ₉₀值（处理后3 wk所需茎生物量减少90％所需的quizalofop-p-ethyl剂量）范围从33至72公顷^-1。在科罗拉多州，堪萨斯州和俄克拉何马州进行的总共5个站点-年的田间研究表明，秋天或春季，在≥77 g ai ha ^-1施用quizalofop-p-ethyl提供了整季的黑麦控制在92- 100％抗quizalofop冬小麦。不管测试的速率和施用时间如何，与未处理的杂草检查相比，在科罗拉多州和俄克拉何马州，由于降低了野生黑麦的竞争性，喹唑啉-对乙基处理可保护冬小麦减产17-27％。结果表明，在秋季或春季以标记的使用量（77–92 g ai ha ^-1）使用quizalofop-p-ethyl可以有效地控制耐quizalofop的冬小麦。