Precise quantification of the fitness cost of synthetic auxin resistance has been impeded by lack of knowledge about the genetic basis of resistance in weeds. Recent elucidation of a resistance‐endowing IAA16 mutation (G73N) in the key weed species kochia (Bassia scoparia), allows detailed characterization of the contribution of resistance alleles to weed fitness, both in the presence and absence of herbicides. Different G73N genotypes from a segregating resistant parental line (9425) were characterized for cross‐resistance to dicamba, 2,4‐d and fluroxypyr, and changes on stem/leaf morphology and plant architecture. Plant competitiveness and dominance of the fitness effects was quantified through measuring biomass and seed production of three F₂ lines in two runs of glasshouse replacement series studies.

中文翻译：

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赋予IAA16突变的麦草畏抗性导致严重的营养生长缺陷，并降低了地肤（Bassia scoparia）的竞争力。

缺乏对杂草抗性遗传基础的认识，阻碍了对合成植物生长素抗性的适应性成本的精确量化。最近对关键杂草物种地肤（Bassia scoparia）中赋予抗药性的IAA16突变（G73N）的研究，可以详细表征在存在和不存在除草剂的情况下，抗性等位基因对杂草适应性的贡献。来自分离的抗性亲本系（9425）的不同G73N基因型对麦草畏的交叉抗性为2,4 d。和氟草烟，以及茎/叶形态和植物结构的变化。通过在两次温室替换系列研究中测量3条F ₂系的生物量和种子产量，量化了植物的竞争力和适应性优势。