In the context of canola (Brassica napus L.)-winter wheat (Triticum aestivum L.) rotational systems, the timing of canola stubble availability and effective weed management play a crucial role in the production of a subsequent winter wheat phase. This study, conducted from 2018 to 2022 across the Canadian prairies, applied a genotype × environment × management framework to examine how manipulations to canola harvest management can help optimize winter wheat production. The factorial treatment structure included two canola hybrids (early- and late-maturing), three canola harvest management systems (early-timing and conventional windrowing at 40 % and 60 % seed color change, respectively, and straight-cutting at 10 % seed moisture), and three weed management treatments (pre-harvest herbicide for canola, pre-plant herbicide for winter wheat, and pre-harvest+pre-plant herbicides). Windrowing and pre-harvest herbicides were completed simultaneously by retrofitting the swather with an onboard sprayer. Across all 16 site-years, winter wheat planted after a late-maturing canola hybrid demonstrated comparable performance to that after early-maturing canola. However, delaying canola harvest reduced winter wheat yields. Conventional windrowing in conjunction with pre-harvest herbicide or pre-harvest+pre-plant herbicides improved winter wheat yields and enhanced weed management, while maintaining canola seed quality, as no herbicide residues were detected in the harvested seed. Our previous research indicated that in-crop herbicide applications are unnecessary due to the high competitiveness of winter wheat against weeds. This research reaffirms in-crop herbicides could be eliminated and underscores the competitiveness and sustainability that a winter wheat phase offers when integrated in Canadian Prairie cropping systems.

中文翻译：

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油菜籽割草和除草剂处理同时提高序播冬小麦的产量


在油菜 （Brassica napus L.） 的背景下-冬小麦 （Triticum aestivum L.） 轮作系统、油菜茬可用性的时间和有效的杂草管理在随后的冬小麦阶段的生产中起着至关重要的作用。这项研究于 2018 年至 2022 年在加拿大大草原上进行，应用基因型×环境×管理框架来研究油菜籽收获管理的操作如何帮助优化冬小麦生产。析因处理结构包括两种油菜杂交种（早熟和晚熟）、三种油菜收获管理系统（分别为 40% 和 60% 种子颜色变化的早定时和常规割条，以及 10% 种子水分的直切）和三种杂草管理处理（油菜籽收获前除草剂、冬小麦种前除草剂和收获前 + 种前除草剂）。通过使用机载喷雾器改造割草机，同时完成堆垛和收获前除草剂。在所有 16 个地点年份中，晚熟油菜杂交种后种植的冬小麦表现出与早熟油菜后相当的性能。然而，推迟油菜籽收获降低了冬小麦产量。传统割草机与收获前除草剂或收获前 + 种植前除草剂相结合，提高了冬小麦产量并加强了杂草管理，同时保持了油菜籽的质量，因为在收获的种子中没有检测到除草剂残留。我们之前的研究表明，由于冬小麦对杂草的竞争力很高，因此没有必要在作物内施用除草剂。 这项研究重申了可以消除作物内除草剂，并强调了冬小麦阶段在整合到加拿大草原种植系统时提供的竞争力和可持续性。