Although genetic transformation of soybean dates back to over two decades, the process remains inefficient. Here, we report the development of an organogenesis-based transformation method of soybean that resulted in an average transformation frequency of 18.7%. This improved method resorts to Agrobacterium-mediated transformation of the split-seed explant with an attached partial embryonic axis obtained from an imbibed seed. In addition to the split-seed explant, Agrobacterium strain and preparation were shown to be important for improved transformation. Transformation with Agrobacterium tumefaciens EHA105 generated higher transformation frequencies and number of low copy events compared to the strain EHA101. In this system, phosphinothricin acetyl transferase conferring tolerance to glufosinate was successfully employed for efficiently producing transgenic events. Around 48% of the T1 progeny was demonstrated to be heritable based on molecular analysis and screening with the herbicide Liberty®. This method was shown to be applicable to different genotypes and a few elite lines showed high transformation frequencies. This split-seed system with an attached partial embryonic axis serves not only as an efficient means for high throughput transgenic production for basic research studies but also for the commercial development of transgenic soybean products.

中文翻译：

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改进大豆转化以实现高效、高通量的转基因生产。


尽管大豆的遗传转化可以追溯到二十多年前，但这一过程仍然效率低下。在这里，我们报告了一种基于器官发生的大豆转化方法的开发，该方法的平均转化频率为 18.7%。这种改进的方法采用农杆菌介导的分裂种子外植体的转化，该外植体带有从吸液种子获得的附着的部分胚轴。除了分裂种子外植体之外，农杆菌菌株和制剂对于改进转化也很重要。与菌株 EHA101 相比，用根癌农杆菌 EHA105 进行转化产生了更高的转化频率和低拷贝事件数量。在该系统中，赋予草铵膦耐受性的草丁膦乙酰转移酶被成功地用于有效产生转基因事件。根据分子分析和除草剂 Liberty® 筛选，约 48% 的 T1 后代被证明具有遗传性。该方法被证明适用于不同的基因型，并且一些优良品系表现出高转化频率。这种带有部分胚轴的分裂种子系统不仅可以作为基础研究高通量转基因生产的有效手段，而且还可以用于转基因大豆产品的商业开发。