我查了一下，你說得不錯，一篇看來靠譜的文章說美國85%的大豆是轉基因的

The United States (85%) and Argentina (98%) produce almost exclusively GM soybeans. In these countries, GM soybeans are approved without restrictions and are treated just like conventional soybeans. Producers and government officials in the US and Argentina do not see a reason to keep GM and conventionally bred cultivars separate – whether during harvest, shipment, storage or processing. Soybean imports from these countries generally contain a high amount of GM content.