Rothamsted Research, Hertfordshire, UK.
The Francis Crick Institute, London, UK.
Glob Chang Biol. 2021 Jun;27(11):2416-2425. doi: 10.1111/gcb.15585. Epub 2021 Mar 23.
Weeds represent a significant threat to crop yields and global food security. We analysed data on weed competition from the world's longest running agricultural experiment to ask whether potential yield losses from weeds have increased in response to management and environmental change since the advent of the Green Revolution in the 1960s. On plots where inorganic nitrogen fertiliser has been applied, potential yield losses from weeds have consistently increased since 1969. This was explained by a warming climate, measured as air temperature averaged over the growing season for the weeds, and a shift towards shorter crop cultivars. Weeds also reduced yield proportionally more on plots with higher rates of nitrogen which had higher yields when weeds were controlled; the relative benefit of herbicides was, therefore, proportional to potential crop yield. Reducing yield losses from weed competition is increasingly challenging because of the evolution of herbicide resistance. Our results demonstrate that weeds now represent a greater inherent threat to crop production than before the advent of herbicides and integrated, sustainable solutions to weed management are urgently needed to protect the high yield potential of modern crop genotypes.
杂草对作物产量和全球粮食安全构成重大威胁。我们分析了来自世界上持续时间最长的农业实验的杂草竞争数据，以探讨自 20 世纪 60 年代绿色革命以来，随着管理和环境的变化，杂草可能导致的产量损失是否有所增加。在施用无机氮肥的地块上，自 1969 年以来，杂草造成的潜在产量损失持续增加。这可以通过气候变暖来解释，即生长季节杂草空气温度的平均值，以及作物品种向更短的方向转变。杂草对氮素投入较高的地块的产量影响也更大，因为这些地块在控制杂草时产量更高；因此，除草剂的相对效益与作物的潜在产量成正比。由于除草剂抗性的进化，减少杂草竞争造成的产量损失变得越来越具有挑战性。我们的研究结果表明，与除草剂出现之前相比，杂草现在对作物生产构成了更大的固有威胁，迫切需要综合、可持续的杂草管理解决方案来保护现代作物基因型的高产量潜力。
