Developing herbicide-tolerant varieties by genome editing holds great promise for addressing the worsening weed problems in wheat cultivation¹. Here, we generated transgene-free wheat germplasms harbouring herbicide tolerance mutations that confer tolerance to sulfonylurea-, imidazolinone- and aryloxyphenoxy propionate-type herbicides by base editing the acetolactate synthase (ALS) and acetyl-coenzyme A carboxylase genes. These stackable herbicide tolerance traits provide a potentially powerful tool for weed management. In addition, we found that base editing at the wheat ALS Pro-174 codon (TaALS-P174) endowed wheat with sufficient resistance to nicosulfuron herbicide in MS growth medium to allow selection. When the TaALS-P174 editor was coupled with editors for other targets of interest, co-editing occurred in the nicosulfuron-resistant plants, and selection for resistance in growth medium enriched the frequency of coupled targets by several-fold. This selectable co-editing system has the potential to greatly bolster adoption of base editing for crop improvement applications.

通过基因组编辑开发耐除草剂品种，有望解决小麦种植中日益严重的杂草问题¹。在这里，我们通过对乙酰乳酸合酶（ALS）和乙酰辅酶A羧化酶基因进行碱基编辑，生成了无转基因小麦种质，其具有除草剂耐受性突变，赋予了对磺酰脲类，咪唑啉酮类和芳氧基苯氧基丙酸酯类除草剂的耐受性。这些可堆叠的除草剂耐受性特征为杂草处理提供了潜在的强大工具。此外，我们发现在小麦ALS Pro-174密码子（TaALS-P174）进行碱基编辑后，小麦在MS生长培养基中对烟嘧磺隆除草剂具有足够的抗性，可以选择。当TaALS-P174编辑器与其他感兴趣目标的编辑器结合使用时，在耐烟嘧磺隆的植物中发生了共同编辑，并且在生长培养基中选择抗性可使耦合靶标的频率增加数倍。