Abstract Soybean is prone to weed infestations and yield variability. With the proposition of using intercropping to overcome these problems, this study explored the effects of combinations of different associated crop species and spatial arrangements on grain production and weed control. In a two-year field experiment in western France, soybean was intercropped with buckwheat, lentil, sorghum and sunflower in two spatial arrangements: within-row intercropping and alternate-row intercropping, to investigate their effects on weed control and soybean production. The results showed that the highest soybean yield occurred in the intercropping with lentil, followed by sorghum and sunflower, and finally buckwheat, but this effect varied by year. The opposite species order was obtained for weed control, revealing a trade-off between soybean production and weed control. We also demonstrated that associated species height was related to soybean yield and weed control. Alternate-row intercropping helped to increase soybean production without compromising weed control for sorghum and buckwheat, which have small height difference with soybean. Finally, our paper showed that combining associated species choice and spatial arrangement allows farmers to manage the trade-off between soybean yield and weed control.

中文翻译：

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以大豆为基础的间作中的物种选择和空间排列：推动产量和杂草控制的杠杆

摘要 大豆易受杂草侵扰和产量变异。本研究提出使用间作来克服这些问题，探讨了不同相关作物品种的组合和空间安排对粮食生产和杂草控制的影响。在法国西部进行的为期两年的田间试验中，大豆与荞麦、扁豆、高粱和向日葵以两种空间安排：行内间作和隔行间作，以研究它们对杂草控制和大豆生产的影响。结果表明，大豆产量最高的是与小扁豆的间作，其次是高粱和向日葵，最后是荞麦，但这种影响因年份而异。杂草控制获得相反的物种顺序，揭示了大豆生产和杂草控制之间的权衡。我们还证明相关物种高度与大豆产量和杂草控制有关。交替行间作有助于提高大豆产量，而不会影响高粱和荞麦的杂草控制，因为高粱和荞麦与大豆的高度差异很小。最后，我们的论文表明，将相关物种选择和空间安排相结合，使农民能够在大豆产量和杂草控制之间进行权衡。