Brassica carinata A. Braun (carinata) has become an important oil crop for biofuel production in subtropical regions. Carinata is highly sensitive to acetolactate synthase (ALS)-inhibiting herbicides, limiting its introduction into existing crop rotations. The objective of the study was to develop carinata lines resistant to ALS-inhibiting herbicides. A susceptible carinata line was crossed with a resistant Brassica napus L. line. Lines derived from those crosses were screened at high doses of imidazolinones, which allowed identifying five lines with high levels of resistance. Doses to reduce plant growth 50% (GR₅₀) and cause 50% injury (ID₅₀) were four to nine times greater than susceptible lines. Resistant lines exhibited cross resistance with halosulfuron (sulfonylurea). Resistance was confirmed under field conditions with doses 2X and 4X for imazethapyr and 4X–8X for halosulfuron of their respective label doses. While susceptible lines died, resistant lines exhibited no injury or growth reductions compared with nontreated controls. Sequencing of the ALS gene indicated that all resistant lines carried a Trp574Leu amino acid substitution, a mutation responsible for resistance in other species. Crosses between resistant lines and a susceptible line demonstrated that the inheritance of the mutation corresponded with the resistance phenotype in the F2. The resistance trait behaved as a single, fully dominant allele, which makes it easier to transfer it to carinata lines with desirable agronomic traits. The resistant lines developed here provide flexibility for use in multiple crop rotations and opens the possibility to use ALS-inhibiting herbicides for weed control within this crop's growing season.

中文翻译：

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对乙酰乳酸合酶抑制除草剂抗性的 Brassica carinata A. Braun 的开发


Brassica carinata A. Braun （carinata） 已成为亚热带地区生物燃料生产的重要油料作物。Carinata 对乙酰乳酸合酶 （ALS） 抑制除草剂高度敏感，限制了其引入现有的作物轮作。该研究的目的是开发对 ALS 抑制除草剂具有抗性的 carinata 品系。易感的 carinata 线与抗性的 Brassica napus L. 线交叉。在高剂量咪唑啉酮下筛选来自这些杂交的品系，这允许识别 5 个具有高耐药水平的品系。减少植物生长 50% （GR₅₀） 和造成 50% 伤害 （ID₅₀） 的剂量是易感品系的 4 到 9 倍。抗性品系表现出与卤嘧磺隆（磺酰脲类）的交叉抗性。在田间条件下，以各自标记剂量的 imazethapyr 剂量 2X 和 4X 以及卤嘧磺隆 4X-8X 剂量确认耐药性。虽然易感品系死亡，但与未处理的对照相比，耐药品系没有表现出损伤或生长减少。ALS 基因测序表明，所有抗性品系都携带 Trp574Leu 氨基酸替换，这是一种导致其他物种耐药性的突变。抗性品系和易感品系之间的杂交表明，突变的遗传与 F2 中的抗性表型相对应。抗性状表现为单个完全显性等位基因，这使得它更容易转移到具有理想农艺性状的 carinata 品系。这里开发的抗性品系为多种作物轮作提供了灵活性，并为在该作物的生长季节使用 ALS 抑制除草剂来控制杂草提供了可能性。